Answer is Option (3) for SSC CHSL Chemistry MCQ

Adding powdered activated carbon to water or using of granular activated carbon (GAC) in the water filter can remove bad taste and foul odour. Powdered activated carbon (PAC) is the preferred method when the taste and odour is moderate and infrequent. Activated carbon works by a phenomenon called “Adsorption”, which is where the odour compound is trapped inside the activated carbon and retained, but the material doing the adsorption does not change size.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Ethylene (C₂H₄) is a nonpolar molecule. This is because, unlike a polar molecule, it has an even distribution of electrical charges. Since, the double bond is between two carbon atoms, there is no difference in the electronegativity. This is why, the shared pair of electrons come lie in between those to carbon atoms. As a result, ethylene is a non-polar and linear molecule.

Answer is Option (1) for SSC CHSL Chemistry MCQ

The transition metals have a tendency to lose electrons. Since the electrons in the highest energy level are actually on a lower principal energy number than the ones before them, this makes it relatively easy to lose some or all of their electrons to land in stable state. When these metals form ions, the 4s electrons are always lost first; so, they form only cations (positive ions).

Answer is Option (4) for SSC CHSL Chemistry MCQ

Cinnabarrefers to the common bright scarlet to brick-red form of mercury sulfide (HgS) that is the most common source ore for refining elemental mercury. It is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Oxygen is the most abundant element in the earth’s crust, comprising 46.6% or the crust by weight. Silicon 28%, aluminum 8.2%, iron 5.6%, calcium 4.2%, sodium 2.5%, magnesium 2.4%, potassium, 2.0%, and titanium 0.61% also comprise the crust. Given the abundance of oxygen and silicon, the silicates are the most abundant minerals in the earth’s crust.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Vinegar is a liquid consisting mainly of acetic acid (CH₃COOH) and water. The acetic acid is produced by the fermentation of ethanol by acetic acid bacteria. It is mainly used as a cooking ingredient.

Answer is Option (2) for SSC CHSL Chemistry MCQ

A Bio fertilizer is a substance which contains living microorganisms which, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Rhizobium, Azotobacter, Azospirillum and blue green algae are traditionally used as Biofertilizers.

Best Option : (2) Ammonia occupies an unique bio chemical position being the only inorganic form of nitrogen that is incorporated into organic linkage and thus an obligate intermediate in the utilization of other inorganic sources.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Limestone is used as a raw-material for the manufacture of quicklime (calcium oxide), slaked lime (calcium hydroxide), cement and mortar. Clay and shale are also used as raw materials for the production of cement.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Atomic number of a chemical element is the number of protons found in the nucleus of an atom of that element, and therefore identical to the charge number of the nucleus. It determines the place of an element in the periodic table. In an uncharged atom, the atomic number is also equal to the number of electrons.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Anthracite is the highest rank of coal. It is the most metamorphosed type of coal, in which the carbon content is between 92.1% and 98%. Anthracite coal generally has the highest heating value per ton on a mineral-matter-free basis. Anthracite is often referred to as hard coal.

Answer is Option (4) for SSC CHSL Chemistry MCQ

The Bhopal gas tragedy involved the leakage of poisonous methyl isocyanate (MIC) gas and other chemicals at the Union Carbide India Limited (UCIL) pesticide plant in Bhopal, Madhya Pradesh, on the night of 2–3 December 1984. It is considered the world’s worst industrial disaster.

Answer is Option (3) for SSC CHSL Chemistry MCQ

A first-order reaction is a reaction that proceeds at a rate that depends linearly on only one reactant concentration. In other words, when the reaction rate depends on the first power of concentration of a single reactant,’ it is considered to be first order. The rate of reaction is directly proportional to the concentration of reacting substance. Absorption, distribution, elimination rates are examples of such reaction. The following graph represents concentration of reactants versus time for a first-order reaction:

Answer is Option (1) for SSC CHSL Chemistry MCQ

Stalactites and stalagmites are formed by water dripping or flowing from fractures on the ceiling of a cave. The dominant mineral in them is calcite (calcium carbonate) or CaCaO₃ . Their largest displays are formed in caves of limestone and dolomite. Other minerals that may be deposited include other carbonates, opal, chalcedony, limonite, and some sulfides.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Soldering is the process of joining two metals by the use of a solder alloy, and it is one of the oldest known joining techniques. It is possible because of the property of cohesion, the interaction between adjacent parts of the same body and as acting throughout the interior of substance. Soldering leads to alloy formation at the layer between two metals.

Answer is Option (2) for SSC CHSL Chemistry MCQ

A Galvanic cell, also known as battery, is an electrochemical cell that derives electrical energy from spontaneous redox reactions taking place within the cell. It is typically used as a source of electrical power. By their nature, they produce direct current. A battery is a set of galvanic cells that are connected in parallel.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Ammonia gas that dissolves in water forms a solution of ammonium hydroxide (NH₄OH). This solution (including the gas) is a strong base and will make the solution alkaline.

H₂O + NH₃ ↔ OH^– + NH4 ⁺

Answer is Option (2) for SSC CHSL Chemistry MCQ

The chemistry of the nitrogenous bases is really the key to the function of DNA. It allows something called complementary base pairing. Cytosine can form three hydrogen bonds with guanine, and adenine can form two hydrogen bonds with thymine.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Corrosion can be defined as the deterioration of materials by chemical processes. Of these, the most important by far is electrochemical corrosion of metals, in which the oxidation process M → M⁺ + e^– is facilitated by the presence of a suitable electron acceptor, sometimes referred to in corrosion science as a depolarizer.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Sulfur dioxide (SO₂) and nitrogen oxides (NO_X ) are the principal pollutants that cause acid rain. SO₂ and NO_X emissions released to the air react with water vapor and other chemicals to form acids that fall back to Earth. Power plants burning coal and heavy oil produce over two-thirds of the annual SO₂ emission.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Heavy water is deuterium oxide (2H₂O). It is a form of water that contains a larger than normal amount of the hydrogen isotope deuterium (2H or D, also known as heavy hydrogen), rather than the common hydrogen^-1 isotope (1H or H, also called protium) that makes up most of the hydrogen in normal water.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Amines are organic derivatives of ammonia, in which one, two, or all three of the hydrogens of ammonia are replaced by organic groups. All aliphatic primary amines are stronger bases than ammonia. In aqueous solution, the pKb’s (basicity) of ammonia, methyl amine, dimethylamine, and trimethyl amine are therefore, respectively, 4.74, 3.34, 3.27. and 4.19. In terms of pKb, the strongest bases have the least positive values of pKb. So in aqueous solutions, the strongest bases are: Dimethylamine > methylamine > trimethylamine.>ammonia

Answer is Option (4) for SSC CHSL Chemistry MCQ

Trimix is a breathing gas, consisting of oxygen, helium and nitrogen, and is often used in deep commercial diving. The helium is included as a substitute for some of the nitrogen, to reduce the narcotic effect of the breathing gas at depth. It helps to reduce nitrogen narcosis and to avoid the dangers of oxygen toxicity. With a mixture of three gases, it is possible to create mixes suitable for different depths or purposes by adjusting the proportions of each gas.

Answer is Option (2) for SSC CHSL Chemistry MCQ

The basicity of an acid is the number of hydrogen ions (H+) which can be produced by the ionization of one molecule of the acid in aqueous solution. For example, the basicity of hydrochloric acid is 1 since one molecule of HCl produces one H+ ion in solution. Similarly, the basicity of Disodium phosphate (Na₂HPO₄) is one since it has one H+ displaceable ion.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Linseed oil and castor oils are used mainly as drying agents in paints and varnishes. Linseed oil is generally used in the manufacture of oil paints, drying oil finish or varnish in wood finishing, as a pigment binder in oil paints, as a plasticizer and in the manufacture of linoleum.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain. Human activities are the main cause of acid rain.

Answer is Option (2) for SSC CHSL Chemistry MCQ

The gaseous air pollutants of primary concern in urban settings include sulfur dioxide, nitrogen dioxide, and carbon monoxide; these are emitted directly into the air from the combustion of fossil fuels. Smoke, a collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion, is also a pollutant. Hydrocarbon is an organic compound consisting entirely of hydrogen and carbon.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Dolomite is a common rock-forming mineral. It is a calcium magnesium carbonate with a chemical composition of CaMg(CO₃)₂ . It is the primary component of the sedimentary rock known as dolostone and the metamorphic rock known as dolomitic marble. Dolomite is used in the Pidgeon process for the production of magnesium.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Dry ice, sometimes referred to as “cardice,” is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue. It is useful for preserving frozen foods, ice cream, etc., where mechanical cooling is unavailable.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Sodium bicarbonate (NaHCO₃) is also known as baking soda, bread soda, cooking soda, and bicarbonate of soda. It is primarily used in cooking (baking), as a leavening agent. It reacts with acidic components in batters, releasing carbon dioxide, which causes expansion of the batter and forms the characteristic texture and grain in pancakes, cakes, quick breads, etc.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Using formula of Stoichiometry, 1mol MgCl₂ : 1mol Mg^2+: 2mol Cl^–. There are two moles of chloride ions for every one mole of MgCl₂ . So, if there is one million Mg²⁺ ions in MgCl₂ , there will be two million chloride ions in it.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Exhaust fumes of motor cars, gases produced from coal fire in a closed room and coal gas, all cotain carbon monoxide, which is the cause of their poisonous nature. When carbon monoxide is inhaled, it prevents the oxygen from combining with hemoglobin and instead combines itself with hemoglobin to form carboxyhaemoglobin, which is stable compound. This causes oxygen starvation in the body tissues and eventually causes death by suffocation.

Answer is Option (1) for SSC CHSL Chemistry MCQ

When a volume of air at a given temperature holds the maximum amount of water vapour, the air is said to be saturated. Air is said to be saturated at 100 percent relative humidity when it contains the maximum amount of moisture possible at that specific temperature. When relative humidity reaches 100 percent or is saturated, moisture will condense, meaning the water vapor changes to liquid vapor.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Atoms that have the same number of protons but different numbers of neutrons are called isotopes. For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13 and 14 respectively. The atomic number of carbon is 6, which means that every carbon atom has 6 protons, so that the neutron numbers of these isotopes are 6, 7 and 8 respectively.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Soaps are effective cleaners because they can dissolve and the oil and grease that holds dirt in place. They reduce the surface tension of the solution and enable it to wet things more uniformly. The surfactants in detergents improve water’s ability to wet things, spread over surfaces, and seep into dirty clothes fibers. The surfactant molecules help water to get a hold of grease, break it up, and wash it away.

Answer is Option (3) for SSC CHSL Chemistry MCQ

The atomic radius is a measure of the size of an atom. It is defined as one-half the distance between the nuclei of two identical atoms that are bonded together. Angstrom is the most common unit used for measuring atomic radius. It is equivalent to 1.0 × 10^-10 meters. Under most definitions the radii of isolated neutral atoms range between 30 and 300 pm (trillionths of a metre), or between 0.3 and 3 angstrom.

Answer is Option (2) for SSC CHSL Chemistry MCQ

The method of separation using magnets is used when one of the components is magnetic. So the heterogeneous mixture of iron filings and some other material (such as sulphur powder) can be separated by using magnets. Similarly, a mixture of sand and iron filings can be separated by magnet.

Answer is Option (2) for SSC CHSL Chemistry MCQ

In sequential order, Hydrogen, Oxygen, Carbon and Nitrogen are the most abundant elements by number in the living system. Hydrogen constitutes 49.8% of living systems, while Oxygen constitutes 24.9%; Carbon and Nitrogen account for 24.9% and 0.27% respectively. It is not surprising, therefore, that the living cell is between 60% and 90% water.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Gold, which is not only the most valuable of metals, but also is without its peer in freedom from alloy, is known as the king of metals. Luxurious, classy and beautiful, gold is the most classic and coveted jewelry metal of all. It is also the oldest precious metal known to man.

Answer is Option (3) for SSC CHSL Chemistry MCQ

An oxidizing agent is a chemical species that removes an electron from another species. Fluorine, having the largest positive value of electrode potential, is the strongest oxidizing agent. As a matter of fact, all halogens have a tendency to take up electrons and thus act as strong oxidizing agents. Among them, Fluorine (the most electronegative element) is given a value of 4.0 and is the strongest oxidizing agent which is reflected in its highly positive standard potential (E_o = +2.85 V). The oxidizing power decreases from fluorine to iodine. Fluorine is so strong an oxidizing agent that it is impossible to carry out reactions with it in aqueous solution.

2F₂ +H₂O → 4HF+O₂

Answer is Option (2) for SSC CHSL Chemistry MCQ

There are at least two good arguments for eating organic: fewer pesticides and more nutrients. In the absence of pesticides and fertilizers, plants boost their production of the phytochemicals (vitamins and antioxidants) that strengthen their resistance to bugs and weeds. A major new study has found that organic foods contain higher levels of antioxidants and less harmful chemicals than conventionally farmed produce.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Sodium hypochlorite bleaches are also called chlorine or liquid household bleach. They are the more powerful laundry bleaches; they are used to whiten and disinfect laundry, is typically either 5.25 percent (regular strength) or 6 percent sodium hypochlorite (ultra strength).

Answer is Option (1) for SSC CHSL Chemistry MCQ

Sodium Nitrate (NaNO₃) is also known as Chile saltpeter or Peru saltpeter (due to the large deposits found in the Atacama desert in these countries) to distinguish it from ordinary saltpeter, potassium nitrate. Also known as soda niter, it is used in the production of fertilizers, pyrotechnics and smoke bombs, glass and pottery enamels, food preservatives, and solid rocket propellant.

Answer is Option (1) for SSC CHSL Chemistry MCQ

A homogeneous mixture of two or more substances uniformly dispersed throughout a single phase is called solution. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. The solution more or less takes on the characteristics of the solvent including its phase, and the solvent is commonly the major fraction of the mixture.

Answer is Option (1) for SSC CHSL Chemistry MCQ

In 1828, German chemist Friedrish Wohler synthesized first organic compound, urea in the laboratory by heating ammonium cyanate (an inorganic compound). NH₄CNO (Ammonium Cyanate)  → NH₂CONH₂ (Urea).

Soon, Kolbe, in 1845, synthesized Acetic acid in laboratory from Carbon, Hydrogen and Oxygen.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Cast Iron is a hard, brittle, nonmalleable iron-carbon alloy, cast into shape, containing 2 to 4.5 percent carbon. Steels contain less than 2% and usually less than 1% carbon, while all cast irons contain more than 2% carbon. Most steel contains less than 0.35 percent carbon. Wrought iron is an iron alloy with very low carbon (0.04 to 0.08%) content.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Mercury and DDT are two persistent toxic materials that accumulate in the food chain and damage the organisms in it. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey. It is now banned because of this.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Noble gas refers to any of the seven chemical elements that make up Group VIIIa of the periodic table. The elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and element 118 (temporarily named ununoctium [Uu]).

Answer is Option (3) for SSC CHSL Chemistry MCQ

Uranium, Thorium and Polonium are radioactive elements which do not have stable naturally occurring isotope. Aluminium is a silvery white, soft, ductile metal. It is the third most abundant element (after oxygen and silicon), and the most abundant metal in the Earth’s crust.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Washing Soda is essentially Sodium Carbonate, a sodium salt of carbonic acid (soluble in water). The molecular formula of washing soda is Na₂CO₃.10H₂O. It is used as an agent to soften hard water. It reacts with the calcium and magnesium bonds present in the water, enabling the detergent to work.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Hydrochloric acid was historically called acidumsalis, muriatic acid, and spirits of salt because it was produced from rock salt and green vitriol and later from the chemically similar substances common salt and sulfuric acid. Hydrochloric acid is found naturally in gastric acid.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Neon is used in neon discharge lamps and advertising signs because the neon lights are visible from long distances. Since the light of neon signs has a better penetrating power through fog and mist, the neon signs are also used in beacon lights for the safety of air and sea navigation.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Sodium bicarbonate (NaHCO₃) is also known as baking soda. It is a chemical leavening agent which is added to baked goods before cooking to produce carbon dioxide and cause them to ‘rise’.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Sodium chloride, also known as salt, common salt, table salt or halite, is an ionic compound with the chemical formula NaCl, representing equal proportions of sodium and chlorine. In the form of table salt, it is commonly used as a condiment and food preservative.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Cryolite (Na₃ AlF₆ , sodium hexafluoroaluminate) does not contain oxygen. It occurs as glassy, colorless, white-reddish to gray-black prismatic monoclinic crystals. Cryolite is used as an insecticide and a pesticide. It is also used to give fireworks a yellow color.

Answer is Option (2) for SSC CHSL Chemistry MCQ

All acids contain hydrogen atom (s). Dilute acids react with some metals such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H₂ SO₄ ) to form a normal salt, Sodium Sulphate (Na₂ SO₄ ). If only one atom of hydrogen is replaced by sodium, it forms an acid salt, Sodium Hydrogen Sulphate (NaHSO₄ ).

Answer is Option (3) for SSC CHSL Chemistry MCQ

The melting point of the given metals (in Celsius) are:- Gold: 1063; Silver: 961;Copper: 1083; Mercury: -38.86. Mercury is the only elemental metal known to melt at a generally cold temperature.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Methane gas is a hydrocarbon gas largely composed of methane formed when organic material or vegetation decays in the absence of air. Naturally occurring methane is mainly produced by the process of methanogenesis. It is also known as Swamp Gas.

Answer is Option (1) for SSC CHSL Chemistry MCQ

An emulsion of sodium thiosulfate is called hypo by photographers. It is used to stop development of exposed film. Thiosulfate converts undeveloped silver bromide grains in the film into water-soluble silver thiosulfate complexes that can be removed when the film is washed.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Silicon carbide, also known as carborundum, is a compound of silicon and carbon with chemical formula SiC. It occurs in nature as the extremely rare mineral moissanite. Silicon carbide powder has been mass-produced since 1893 for use as an abrasive.

Answer is Option (2) for SSC CHSL Chemistry MCQ

A mole of a gas is the amount of a substance containing 6.023 x 10²³ atoms. This is known as Avogadro’s number. 1 mole contains the same number of particles as there are in 12 g of carbon-12 atoms by definition. 12 g of carbon^-12 atoms = 6.022 x 10²³ carbon atoms.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Neutrons are the particles in an atom that have a neutral charge. So, if an atom has equal numbers of electrons and protons, the charges cancel each other out and the atom has a neutral charge. Hydrogen (H) has 1 proton and 1 electron; it does not have any neutron in its nucleus.

Answer is Option (4) for SSC CHSL Chemistry MCQ

(The calorific value of Gasoline is 47,300 kJ/kg. The calorific value of a fuel is the quantity of heat produced by its combustion – at constant pressure and under “normal” conditions (i.e. to 0⁰ C and under a pressure of 1,013 mbar).

Answer is Option (1) for SSC CHSL Chemistry MCQ

In 1911 Ernest Rutherford used experimental evidence to show that an atom must contain a central nucleus. Niels Bohr further developed Rutherford’s nuclear atom model. He used experimental evidence to support the idea that electrons occupy particular orbits or shells around the nucleus of an atom.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Sodium carbonate (Na₂CO₃) is also known as washing soda, soda ash and soda crystals. It is a salt of carbonic acid, a chemical that produces a wide range of salts collectively known as carbonates. It can be used to remove stubborn stains from laundry.

Answer is Option (3) for SSC CHSL Chemistry MCQ

The fundamental reason for the bonding of atoms is that they lose their stored potential energy by forming bonds. This is the only reason for chemical combination. So, when a bond is formed between two atoms, stored potential energy is always released to the surroundings. However, according to the Law of Conservation of Energy, a bond cannot form unless this bond energy is transferred from the interacting atoms to the rest of the system. So overall the energy of the system remains the same.

Answer is Option (1) for SSC CHSL Chemistry MCQ

LD₅₀ (Lethal Dose 50) is the amount of a solid or liquid material that it takes to kill 50% of test animals (for example, mice or rats) in one dose. LD₅₀ is one way to measure the short-term poisoning potential (acute toxicity) of a material. LC₅₀ is the concentration of a material in air that will kill 50% of the test subjects when administered as a single exposure.

Answer is Option (2) for SSC CHSL Chemistry MCQ

An example of a dibasic acid is sulphuric acid H₂ SO₄ . Dibasic acids yield two free hydrogen ions in solution for each molecule of acid ionized.

H₂ SO₄ → 2H⁺ + SO₄^2–

Answer is Option (1) for SSC CHSL Chemistry MCQ

The primary greenhouse gases in the Earth’s atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse effect, the most important are: Water vapour and clouds: 36-72 %, Carbon Dioxide: 9-26 %, Methane: 4-9 % and Ozone: 3-7 %.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Fires require these 3 things: a fuel (a hydrocarbon, which is a compound containing only carbon and hydrogen), a source of oxygen, and heat. Carbon Dioxide is most commonly used to extinguish fire as it displaces oxygen, thus choking the very source of a fire.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Nichrome is a mixture of chromium and nickel. Nichrome wire is a great conductor of electricity. Nichrome is used to make heating coils and other types of elements in household appliances.

Answer is Option (1) for SSC CHSL Chemistry MCQ

The extent to which an electrolyte dissociates into ions is known as degree of dissociation or ionization and depends upon the following factors:

(1) Nature of the electrolyte,

(2) Temperature,

(3) Dilution,

(4) nature of the solvent, and

(e) presence of other ions.

Answer is Option (3) for SSC CHSL Chemistry MCQ

The main gases responsible for causing acid rain are sulphur dioxide as well as nitrous oxides. The main sources of sulphur dioxide are metal working industries and coal-fired power stations whereas nitrous oxide is from vehicles and fuel combustion.

Answer is Option (3) for SSC CHSL Chemistry MCQ

The pH level of lemon juice is, 2.00 to 2.60. It varies depending on the lemon. pH expresses different levels of acidity or alkalinity within a solution.

Answer is Option (2) for SSC CHSL Chemistry MCQ

A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members of its ring (s). Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.

Answer is Option (3) for SSC CHSL Chemistry MCQ

In electro-refining, the anodes consist of unrefined impure metal, and as the current passes through the acidic electrolyte the anodes are corroded into the solution so that the electroplating process deposits refined pure metal onto the cathodes. Electrolytic refining is used to extract impurities from crude metals.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Natural rubber consists of suitable polymers of the organic compound isoprene, with minor impurities of other organic compounds plus water. Isoprene is produced and emitted by many species of trees into the atmosphere (major producers are oaks, poplars, eucalyptus, and some legumes).

Answer is Option (2) for SSC CHSL Chemistry MCQ

Calcination involves simple decomposition of ore on heating below its melting point usually in absence of air to produce new compounds having higher percentage of metal as well as removing the moisture, organic matter and volatile impurities. Calcination makes the ore porous.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Electronegativity of the elements using the Pauling Scale is as follows: Fluorine: 3.98, Oxygen: 3.44, Chlorine: 3.16, and Sodium: 0.93. Electronegativity increases down the group and decreases down the period.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Ammonium chloride (NH₄Cl) is generally considered as an ionic compound but this compound has three different types of bond. There is ionic bond between NH₄ ^{+ ion} and Cl^{– ion}. There are N-H covalent bonds. The formation of NH ^{4 +} from NH³ is sometimes described as the formation of a coordinate bond between NH³ and H⁺ , however once the bond is formed there is no difference between the four N-H bonds, NH^{4 +} has a tetrahedral structure.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion. Chlorofluorocarbon (CFC) is an organic compound that contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane and ethane.

Answer is Option (1) for SSC CHSL Chemistry MCQ

The maximum permissible limit for fluoride in drinking water in India is 1.5 milligrams per liter (mg/L). The desirable limit is 1 mg/L.

Fluoride levels above 1.5 mg/L can cause dental fluorosis, which includes discoloration and mottling of teeth.

Fluoride levels above 5 mg/L can cause bone fluorosis.

A low concentration of fluoride (around 0.5 mg/L) can help prevent tooth decay.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Bromine belongs to the halogen group. It is the only non-metal element that is in a liquid form at room temperature. At room temperature it is a reddish brown fuming liquid with an unpleasant chlorine like smell.

 Answer is Option (2) for SSC CHSL Chemistry MCQ

Synthetic detergents are made from sodium salt of benezene sulphonic acid.

Answer is Option (1) for SSC CHSL Chemistry MCQ

The sewage obtained from water closets and urinals in known as Sanitary waste.

Answer is Option (3) for SSC CHSL Chemistry MCQ

As per IS 10500:2012, Total Hardness Acceptable is 200 mg/L and Cause for Rejection 600 mg/L

And, Total Dissolved Solids – Acceptable is 500 mg/L and Cause for Rejection 2000 mg/L

The permissible/desirable drinking water standard for total hardness is 200 mg/L and the permissible limits in absence of an alternate source of water for total Hardness and total dissolved solids in the drinking water respectively will be 600 ppm and 2000 ppm.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Ion-exchange method is also called the zeolite/permutit process. In this method, the permanent hardness of water is removed by using resins.

Distillation is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation.

Carding is a form of credit card fraud in which a stolen credit card is used to charge prepaid cards. Both Ion exchange and distillation are used for reducing the TDS in water.

Therefore, Both A and B is the answer.

Answer is Option (4) for SSC CHSL Chemistry MCQ

A mixture of water and alcohol is separated by the process of distillation. At 78⁰C, alcohol starts to vaporize. The vapours are condensed in the condenser and alcohol is collected in the receiver.

Answer is Option (2) for SSC CHSL Chemistry MCQ

Acid rain is caused by emissions of sulfur dioxide and nitrogen oxides, which react with the water molecules in the atmosphere to produce acids.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Paper is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Biodiesel production is the process of producing the biofuel, biodiesel, through the chemical reactions trans-esterification and esterification. This involves vegetable or animal fats and oils being reacted with short-chain alcohols (typically methanol or ethanol).

Answer is Option (4) for SSC CHSL Chemistry MCQ

The main use of litmus is to test whether a solution is acidic or basic. For instance, ammonia gas, which is alkaline, colours the red litmus paper blue.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Lead pollution primarily came from cars in the past. Today, lead pollution primarily comes from lead smelters, metal processing plants and incinerators. Deposits of lead in soil can harm both humans and animals by absorbing it into a body.

 Answer is Option (2) for SSC CHSL Chemistry MCQ

Bunker Gear or “Turnout Gear” are terms used by many firefighters to refer to their system of outer protective clothing. Fire fighter used to be made of asbestos in the past. Because of its carcinogenic properties and other harmful effects, it has slowly been replaced by other substitutes. Fire-fighting and working clothes and accessories for firemen, rescuers and industrials made of materials FR cotton, Nomex, Modacryl, FR viscose and others.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Water gas, a mixture of carbon monoxide and hydrogen, is produced by treating carbon (in the form of coke or coal) with steam at high temperatures.

Answer is Option (3) for SSC CHSL Chemistry MCQ

Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties. By comparison, bronze is principally an alloy of copper and tin.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Rust is composed of iron oxides. In colloquial usage, the term is applied to red oxides, formed by the reaction of iron and oxygen in the presence of water or air moisture. When impure (cast) iron is in contact with water, oxygen, or other strong oxidants, or acids, it rusts. If salt is present, for example in seawater or salt spray, the iron tends to rust more quickly, as a result of electrochemical reactions.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Oil and grease traps are small size skimming basins provided to remove oil and grease and other small floating materials such as fats, vegetable debris, fruit skins, etc. It is so designed that lighter materials like grease and oil content of wastewater rise to the surface of wastewater and remains on top of liquid until removed.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Coal worker’s pneumoconiosis, colloquially referred to as black lung disease, is a lung disease that results from breathing in dust from coal, graphite, or manmade carbon over a long period of time. Inhaled coal dust progressively builds up in the lungs and is unable to be removed by the body; that leads to inflammation, fibrosis, and in worse cases, necrosis.

Answer is Option (4) for SSC CHSL Chemistry MCQ

Lignite, often referred to as brown coal, is a soft brown fuel with characteristics that put it somewhere between coal and peat. It is considered the lowest rank of coal. It has a carbon content of around 25- 35%, a high inherent moisture content sometimes as high as 66%, and an ash content ranging from 6% to 19% compared with 6% to 12% for bituminous coal.

Answer is Option (1) for SSC CHSL Chemistry MCQ

Coal tar is a brown or black liquid of extremely high viscosity. In the coal gas era, there were many companies in Britain whose business was to distill coal tar to separate the higher-value fractions, such as naphtha, creosote and pitch. Naphthalene is derived from a kind of naphtha (a broad term encompassing any volatile, flammable liquid hydrocarbon mixture, including coal tar).