Question

D) TUULUU
4.
If a pure compound is composed of X,Yz
molecules and consists of 60% X by weight, what
is the atomic weight of Y in term of atomic weight
of X?
​

Answer 1

your question is incorrect. A correct question is ---> If a pure compound is composed of X2Y3. molecules and consists of 60% X by weight , what is the atomic weight of Y in term of atomic weight of X.

solution : A pure chemical compound is X2Y3.

Let molar mass of compound is 100g

so, 2X + 3Y = 100 ......(1)

given, 60% of X by weight.

so, 60g of X in 100g of compound.

now, 60 + 3Y = 100

3Y = 40 => Y = 40/3 g ......(2)

putting equation (2) in equation (1),

X = 30g

now, atomic weight of Y in term of atomic weight of X = atomic weight of Y/atomic weight of X × 100

= (40/3)/30 × 100

= 400/9 = 44.44%

hence, answer is 44.44%