Solving Law of Multiple Proportions w/ Elements X and Y

Question

Elements X and Y form 2 compounds. 1.00 g of the first compound contains 0.33 g of X, 1.00 g of the other compound contains 0.42 g of X. Identify a plausible set of formulas.

 

Answer Choices: (Only 1 Correct)

 

X4Y2 and X3Y
X3Y and X2Y2
X3Y and X4Y
XY3 and XY4
XY and X3Y3

Answer 1

0.33 g of X; .67 g Y

 

.33g X/.67g Y  =.5

 

0.42 g of X; .58 g Y

 

.42 g X/.58 g Y = .72

 

.72/.5 = 1.45 = 1.5 = 3/2

 

So, the answer is X3Y and X2Y2, because these two compounds have X to X ratio of 3 to 2