Question

Magnesium reacts with hydrochloric acid (HCl) as follows. mc025-1.jpg How many milliliters of hydrogen gas are produced by the reaction 0.020 mol of magnesium with excess of hydrochloric acid at STP? 0.448 mL 0.45 mL 448 mL 450 mL

Answer 1

Answer: 448 mL of hydrogen gas.

Solution:

$Mg(s)+HCl(aq)\rightarrow MgCl_2(aq)_+H_2(g)$

Now,according to reaction

1 mole of magnesium produces one mole of hydrogen gas.

Then 0.020 moles of magnesium will produce 0.020 moles of hydrogen gas.

Moles of $H_$ gas : 0.020 mol

At STP, 1 mol of gas occupies 22.4 L

So volume of 0.020 mol of $H_2$produced at STP :

= 22.4/times 0.020 = 0.448 L = 448 mL    (1L=1000mL)

Answer 2

Magnesium reacts with hydrochloric acid (HCl) as follows. There are 0.45 milliliters of hydrogen gas are produced by the reaction 0.020 mol ofmagnesium with excess of hydrochloric acid at STP.