Question

Question 32 4 pts When decomposed chemically, 73.0 grams of a sample of HCl produce 71.0 g of C12 and 2.0 g of H2, while 53.5 g of a sample of HCl produce 1.5 g of H2 and 52.0 g of C12. Which of the following laws do these experiments illustrate? 1. Law of Conservation of Mass 11. Law of Constant Composition III. Law of Multiple Proportions I, II and III O and 11 ll only 0 Tonly and I Previous Next →

Answer 1

The correct answer is I and II.

Law of conservation of mass: the total mass of reactants remains equal to the total mass of products in a chemical reaction.

Law of constant composition: the ratio (or percentage) of masses of the elements in a given compound remains the same.

I sample :- mass of HCl (73.0 g) mass of Us (71.0 g) + mass of H₂ (2008) je. mass of reactant = total mass of products. It verifies law of conservation of mass. Now, % H₂ 2.0 g x 100 2.74% 7.3.0 g % Cl2 = 71.0 g Xloo 73.0 g = 97.26 7. I sample :- Mass of Ha (s3 S 8) = mass of ₂ (5200 g) + mass of H₂ ( 1.5g) → law of conservation of mas holds good. 1.5 Now % H₂ go X100 2.80 % 53.5 g % U 52:0 g = X100 = 97.2 °C 53.5 8

It can be seen that the percentages of hydrogen and chlorine in the two samples are almost same (within the experimental error). So they illustrate the law of constant composition as well.

Note: the law of multiple proportions applies to more than one compound of two elements.