Question

Suppose there are two known compounds containing the generic elements X and Y. You have a 1.00 g sample of each compound. One sample contains 0.31 g of X and the other contains 0.40 g of X. Identify plausible sets of formulas for these two compounds. X2Y and X3Y X2Y5 and X3Y5 XY and X2Y X3Y and X4Y XY3 and XY4 XY and X3Y X4Y2 and X3Y

Answer 1

Given that

first compound having 0.32 g of X in 1 g then mass of Y = 1- mass of X = 1- 0.31 =0.69 g

second compound having 0.40 g of X in 1 g then mass of Y = 1- mass of X = 1- 0.40 =0.60 g

first compound

mass ratio = mass of Y / mass of X = 0.69 / 0.31 = 2.2258

second compound

mass ratio = mass of Y / mass of X = 0.60 / 0.40 = 1.5

ratio of mass ratio = 2.2258 / 1.5 = 1.48

nearly = 1.5

1) X2Y and X3Y

X2Y atom ratio = 1/2

X3Y atom ratio = 1/3

ratio of atom ratio = (1/2) / (1/3) = 1.5

2)

X2Y5 and X3Y5

X2Y5 atom ratio = 5/2

X3Y5 atom ratio = 5/3

ratio of atom ratio = (5/2) / (5/3) = 1.5

3) XY and X2Y

XY atom ratio = 1

X2Y atom ratio = 1/2

ratio of atom ratio = (1) / (1/2) = 2

4) X3Y and X4Y

X3Y atom ratio = 1/3

X4Y atom ratio = 1/4

ratio of atom ratio = (1/3) / (1/4) = 1.33

5) XY3 and XY4

XY3 atom ratio = 3

XY4 atom ratio = 4

ratio of atom ratio = (3) / (4) = 0.75

6) XY and X3Y

XY atom ratio = 1

X3Y atom ratio = 1/3

ratio of atom ratio = (1) / (1/3) = 3

7) X4Y2 and X3Y

X4Y2 atom ratio = 2/4

X3Y atom ratio = 1/3

ratio of atom ratio = (2/4) / (1/3) = 1.5

1,2, 7 are having the same ratio of atom ratios

1, 2 , 7 are the possible molecular compound pairs