Question

The mass of 224 mL of hydrogen gas at STP is
(A) 0.02 g
(C) 2.24 g
(B) 0.224 g.1.0
(D) 20.0 g​

Answer 1

Answer:

0.02 g

Explanation:

at STP Volume(in litre) = no.of moles * 22.4

Answer 2

$moles \: = \: \frac{volume \: of \: gas \: }{22.4 \: l} \\ moles = \frac{volume \: of \: gas \: }{22400 \: ml} \\ moles = \frac{224}{22400} \\ moles = \frac{1}{100} \\ \\ also \\ \\ moles \: = \frac{given \: mass}{molar \: mass} \\ \\ molar \: mass \: of \: hydrogen \: gas \: is \: 2 \\ \\ \frac{1}{100} = \frac{given \: mass}{2} \\ \\ given \: mass \: = \frac{1}{50} \: g \: or \: 0.02 \: g$

there you go :)