Question

Consider the following reaction:

Mg(s) + 2 HC1(aq)= MgC1₂(aq) + H_{2 (g)}

The total pressure of gas collected over water is 785.0 mmHg and the temperature is 25.0^•C. What is the pressure of hydrogen gas formed in mmHg?

Answer 1

$P_1=785mmHg$

$P_2=unknown$

$T_1=273k$

$T_2=298k$

From the ideal gas equation;(Gay lussacs law)

$P_2=P_1$ $\times$ $V\over V$ $\times$ $T\over T$ $=P_1$ $\times$ $T\over T$

$=785mmHg\times$ $298k\over 273k$

$=856.89mmHg$