5 moles of AB2 weigh 125 × 10-3 kg and 10 moles of A2B2 weigh 300 × 10-3 kg. The molar mass of A(MA) and molar mass of B(MB) in kg mol-1 are :

Question

5 moles of AB2 weigh 125 × 10-3 kg and 10 moles of A2B2 weigh 300 × 10-3 kg. The molar mass of A(MA) and molar mass of B(MB) in kg mol-1 are : (A) MA = 50 × 10-3 and MB = 25 × 10-3 (B) MA = 25× 10-3 and MB = 50× 10-3 (C) MA = 5 × 10-3 and MB = 10 × 10-3 (D) MA = 10 × 10-3 and MB = 5 × 10-3

Tardigrade Admin · Accepted Answer

5[MA + 2MB] = 125 MA + 2MB = 25 ....(1) 2MA + 2MB = 30 ....(2) from eq. (1) (2) MA = 5 MB = 10

Q. $5$ moles of $A B_{2}$ weigh $125 \times 1 0^{- 3} k g$ and $10$ moles of $A_{2} B_{2}$ weigh $300 \times 1 0^{- 3} k g$ . The molar mass of $A (M_{A})$ and molar mass of $B (M_{B})$ in $k g m o l^{- 1}$ are :

$M_{A} = 50 \times 1 0^{- 3}$ and $M_{B} = 25 \times 1 0^{- 3}$

$M_{A} = 25 \times 1 0^{- 3}$ and $M_{B} = 50 \times 1 0^{- 3}$

$M_{A} = 5 \times 1 0^{- 3}$ and $M_{B} = 10 \times 1 0^{- 3}$

$M_{A} = 10 \times 1 0^{- 3}$ and $M_{B} = 5 \times 1 0^{- 3}$

$5 [M_{A} + 2 M_{B}] = 125$
$M_{A} + 2 M_{B} = 25$ ....(1)
$2 M_{A} + 2 M_{B} = 30$ ....(2)
from eq. (1) & (2)
$M_{A} = 5$
$M_{B} = 10$

Q. 5 moles of AB2​ weigh 125×10−3kg and 10 moles of A2​B2​ weigh 300×10−3kg. The molar mass of A(MA​) and molar mass of B(MB​) in kgmol−1 are :

MA​=50×10−3 and MB​=25×10−3

MA​=25×10−3 and MB​=50×10−3

MA​=5×10−3 and MB​=10×10−3

MA​=10×10−3 and MB​=5×10−3