Nature of Matter & Laws of Combination — Practice Questions

Free NEET Chemistry multiple-choice questions on Nature of Matter & Laws of Combination. Attempt each question and reveal the answer with a full explanation.

Which of the following laws directly relates the volume of reacting gases and product gases at the same temperature and pressure? Gay-Lussac's Law Law of Multiple Proportions Avogadro's Law Law of Conservation of Mass The law of conservation of mass was experimentally verified by Landolt. Which of the following best describes this law? Mass can neither be created nor destroyed in a chemical reaction A compound always contains the same elements in a fixed ratio by weight Equal volumes of gases contain equal number of molecules Matter is made up of indivisible atoms A student performs an experiment and gets results 10.12 g and 10.14 g . The true value is 15.00 g . These results are: Precise but not accurate Accurate but not precise Both accurate and precise Neither accurate nor precise Which of the following laws explains why the percentage of copper in 'cupric carbonate' is the same whether it is of natural origin or synthesized in a lab? Law of definite proportions Law of multiple proportions Law of conservation of mass Avogadro's Law According to the Law of Multiple Proportions, if elements A and B form compounds AB and AB 2 , then for a fixed mass of A, the masses of B are in the ratio: 1:2 1:1 2:1 3:2 The percentage of oxygen in NaOH is: 40% 16% 60% 25% The law of multiple proportions is NOT illustrated by: NaCl and NaBr CO and CO 2 SO 2 and SO 3 N 2O and NO Which of the following terms describes the closeness of a set of measurements to each other? Precision Accuracy Significant figures Standardization Which of the following pairs of gases illustrates the Law of Multiple Proportions? NO and NO 2 CO and CO 2 H 2O and D 2O Both NO and NO 2 and CO and CO 2 A sample of ammonia ( NH 3 ) contains 82.35 % Nitrogen and 17.65 % Hydrogen. This data supports: Law of Definite Proportions Law of Multiple Proportions Law of Conservation of Mass Gay-Lussac's Law Which of the following statements about 'Precision' is correct? It refers to the closeness of various measurements for the same quantity. It refers to the agreement of a particular value to the true value. It is always equal to the accuracy of the instrument. It depends on the number of entities in one mole. Which of the following is an example of an extensive property? Mass Density Temperature Molarity Which law states that gases combine in a simple ratio of their volumes at constant temperature and pressure? Gay-Lussac's Law Avogadro's Law Boyle's Law Charles's Law According to the rules of rounding off, if the digit to be dropped is 5 and the preceding digit is even, then: The preceding digit is left unchanged The preceding digit is increased by 1 The preceding digit is decreased by 1 The preceding digit is doubled Which of the following ratios illustrates the Law of Multiple Proportions for elements Nitrogen and Oxygen? NO and NO2 NH3 and N2H4 NaCl and NaBr H2O and D2O In a face –centered cubic lattice, a unit cell is shared equally by how many unit cells :- 4 2 6 8 The appearance of colour in solid alkali metal halides is generally due to : F-centres Schottky defect Frenkel defect Interstitial positions For a cubic crystal structure which one of the following relations indicating the cell characteristics is correct? a b c and = = = 90° a = b = c and 90° a = b = c and = = = 90° a b c and and 90° The Langmuir adsorption isotherm is deduced using the assumption the adsorption sites are equivalent in their ability to adsorb the particles the heat of adsorption varies with coverage the adsorbed molecules interact with each other the adsorption takes place in multilayers. Which of the following anions is present in the chain structure of silicates? (Si 2 O 5 2- ) n (SiO 3 2- ) n SiO 4 4- Si 2 O 7 6- Which one of the following characteristics is associated with adsorption ? G is negative but H and S are positive G , H and S all are negative G and H are negative but S is positive G and S are negative but H is positive Natural rubber has All cis-configuration All trans-configuration Alternate cis-and trans-configuration Random cis-and trans-configuration The number of significant figures in 0.002030 is: 4 6 3 2 Fog is colloidal solution of :- Liquid in gas Gas in liquid Solid in gas Gas in gas Which of the following absorbs carbon dioxide and releases oxygen? K2O CaO KO2 KOH The biodegradable polymer is: Buna-S Nylon-6,6 Nylon-2-Nylon 6 Nylon-6 The percentage of copper in CuSO 4 5H 2O is (Atomic mass of Cu=63.5, S=32, O=16, H=1 ): 25.45 % 39.81 % 32.12 % 45.90 % The law of reciprocal proportions can be illustrated by which of the following set of compounds? H 2O, SO 2, H 2S NH 3, N 2O 5, N 2O CO, CO 2, O 2 NaCl, NaBr, NaI In which of the following cases is the Law of Multiple Proportions NOT applicable? D 2O and H 2O CO and CO 2 SO 2 and SO 3 PbO and PbO 2 The correct order of increasing thermal stability of K2CO3 , MgCO3 , CaCO3 and BeCO3 is BeCO3 < MgCO3 < CaCO3 < K2CO3 MgCO3 < BeCO3 < CaCO3 < K2CO3 K2CO3 < MgCO3 < CaCO3 < BeCO3 BeCO3 < MgCO3 < K2CO3 < CaCO3 Structures of some common polymers are given which one is not correctly presented ? Regarding cross-linked or network polymers, which of the following statements is incorrect? Examples are bakelite and melamine. They are formed from bi- and tri-functional monomers. They contain covalent bonds between various linear polymer chains. They contain strong covalents bonds in their polymer chains. Match the following : array ll Oxide & Nature (a) CO & (i) Basic (b) BaO & (ii) Neutral (c) Al2O3 & (iii) Acidic (d) Cl2O7 & (iv) Amphoteric array (ii) (i) (iv) (iii) (iii) (iv) (i) (ii) (iv) (iii) (ii) (i) (i) (ii) (iii) (iv) The law of definite proportions was given by: Joseph Proust John Dalton Antoine Lavoisier Gay-Lussac Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In a particular point defect, an ionic solid is electrically neutral, even if few of its cations are missing from its unit cells. Reason (R): In an ionic solid, Frenkel defect arises due to dislocation of cation from its lattice site to interstitial site, maintaining overall electrical neutrality. In the light of the above statements, choose the most appropriate answer from the options given below: Both (A) and (R) are correct but (R) is not the correct explanation of (A) (A) is correct but (R) is not correct (A) is not correct but (R) is correct Both (A) and (R) are correct and (R) is the correct explanation of (A) Which statement regarding polymers is not correct? Fibers possess high tensile strength Thermoplastic polymers are capable of repeatedly softening and hardening on heating and cooling respectively Thermosetting polymers are reusable Elastomers have polymer chains held together by weak intermolecular forces Match List-I with List-II array ll List-I & List-II (a) Li & (i) absorbent for carbon dioxide (b) Na & (ii) electrochemical cells (c) KOH & (iii) coolant in fast breeder reactors (d) Cs & (iv) photoelectric cell array Choose the correct answer from the options given below : (a) - (iii), (b) - (iv), (c) - (ii), (d) - (i) (a) - (i), (b) - (iii), (c) - (iv), (d) - (ii) (a) - (ii), (b) - (iii), (c) - (i), (d) - (iv) (a) - (iv), (b) - (i), (c) - (iii), (d) - (ii) Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : Assertion A : Metallic sodium dissolves in liquid ammonia giving a deep blue solution, which is paramagnetic. Reason R : The deep blue solution is due to the formation of amide. In the light of the above statements, choose the correct answer from the options given below : Both A and R are true and R is the correct explanation of A Both A and R are true but R is NOT the correct explanation of A A is true but R is false A is false but R is true Which of the following statements are NOT correct? A. Hydrogen is used to reduce heavy metal oxides to metals. B. Heavy water is used to study reaction mechanism. C. Hydrogen is used to make saturated fats from oils. D. The H-H bond dissociation enthalpy is lowest as compared to a single bond between two atoms of any elements. E. Hydrogen reduces oxides of metals that are more active than iron. Choose the most appropriate answer from the options given below: B, C, D, E only B, D only D, E only A, B, C only Which of the following pairs of compounds illustrates the Law of Reciprocal Proportions? H2O, H2S, SO2 H2O, D2O, T2O CO, CO2, O3 Na2O, Na2O2, NaOH Which of the following pairs of compounds illustrate the law of multiple proportions? SnCl 2, SnCl 4 H 2O, D 2O NaCl, NaBr MgO, Mg(OH) 2 Which of the following is the SI unit of luminous intensity? candela mole ampere kelvin According to Gay-Lussac's law of gaseous volumes, when gases combine or are produced in a chemical reaction they do so in a simple ratio by volume, provided all gases are at the same: Temperature and Pressure Temperature and Volume Pressure and Volume Mass and Density Which of the following prefixes is correctly matched with its multiple? femto - 10 -15 pico - 10 -10 nano - 10 -12 micro - 10 -3 Which of the following is a homogeneous mixture? Air Milk Cloud Smoke