Question

How do you solve: you have two distinct gaseous compounds made from element x and y. the mass percents are as follows: compound 1: 30.43% x and 69.57% y. compound 2: 63.64% x and 36?

Answer 1

Let's assume that a unit of compound 1 is 100g and a unit of compound 2 is 100g... in other words, compound 1 will be 30.43g X and 69.57g Y, and compound 2 will be 63.64g X and 36g Y.

According to the given in your problem, we can also write the following two chemical equations:

X+2Y--> 2(compound 1)

2X+Y--> 2(compound 2)

using the 100g units above we can also write this as:

X+2Y--> 2(30.43g X) + 2(69.57g Y)

2X+Y--> 2(63.64g X) + 2(36g Y)

We add these two chemical equations together and get:

3X+3Y--> 2(30.43g+63.64g X) + 2(69.57g+36g Y)

This can be written more simply as:

3X+3Y--> 188.14g X + 211.14g Y

In other words, 3 volumes of X gives 188.14g of X, and 3 volumes of Y gives 211.14g of Y. Dividing one by 3 and you get 62.71g per volume X, and 70.38g per volume Y.

x: 62.71 g/mol.

Y: 70.38 g/mol.