Question

Two samples of sodium chloride with different masses were decomposed into their constituent elements. One sample produced 1.15 g of sodium and 1.77 g of chlorine.Being consistent with the law of constant composition, also called the law of definite proportions or law of definite composition, which set of masses could be the result of the decomposition of the other sample?5.22 g of sodium and 15.7 g of chlorine5.22 g of sodium and 8.04 g of chlorine5.22 g of sodium and 4.18 g of chlorine5.22 g of sodium and 1.45 g of chlorine

Answer 1

So,

We know that the proportion Sodium to Chloride is 1 to 1 in sodium chloride, so we have to look for this proportion in the options

AM Sodium = 23 g

AM Chlorine = 35.5 g

We could use the rule of three as follows:

We have to look for the proportion in the options.

A. 5.22g of sodium = 0.2269 mol

15.7 g of chlorine = 0.44 mol These numbers are not very similar

B. 5.22g of sodium = 0.2269 mol

8.04 g of chlorine = 0.2265 mol These numbers are really similar, so this is the correct option.

The correct answer is B.