An automotive manufacturer wants to design a new air bag, using sodium azide and ferric oxide. Its total volume when inflated will be $24\mathrm{.}4L$ at $25C.$ Its pressure when inflated will be $1\mathrm{.}0$atm. How much of each chemical should the air bag contain?

$6Na{N}_3(s)F{e}_2{O}_3(s)3N{a}_{2}O$

$($s$)+2Fe(s)+9N_2(g)$

a$.2$ moles of sodium azide, $2$ moles of ferric oxide

b$.2$ moles of sodium azide, $\frac{1}{3}$ mole of ferric oxide

c$.2$ moles of ferric oxide, $\frac{1}{3}$ mole of sodium azide

d$.6$ moles of sodium azide, I mole of ferric oxide

e$.$ none of them

$15.$ Calculate the heat for the overall reaction:

$Mg(s)+\frac{1}{3}{O}_3(g)+$MgO$(s)$

Given the heats of reaction below:

$Mg(s)+2$HCI$(aq)MgC{l}_2(aq)+H_2(g),AH=-143$

$kJ,$

MgO$(s)+2$HCI$(aq)MgC{l}_2(aq)+H_{2}O(g),AH=-216kJ$

$H_2(g)+\frac{1}{2}{O}_2(g)H_{2}O(l),AH=-285kJ$

a$.-644kJ$

b$.+644kJ$

d$.-74kJ$

e$.+74kJ$

$16.$ Which process below has been described correctly for a temperature above $274K?$

a$.H_{2}O(l)H_{2}O(s)$ is exothermic and spontaneous.

b$.H_{2}O(l)H_{2}O(s)$ is endothermic and spontaneous.

c$.H2O(g){}_{2}O(l)$ is endothermic and spontaneous.

d$.H_{2}O(s)H_{2}O($l$)$ is exothermic and spontaneous

e$.H_{2}O(s)H_{2}O(l)$ is endothermic and spontaneous.

$17.$ What mass of $ZnC{l}_2($molar mass $136\mathrm{.}3\frac{g}{m}ol)$ can be prepared from the reaction of $3\mathrm{.}27$ grams of zinc $($molar mass$=65\mathrm{.}4\frac{g}{m}ol)$ with $3\mathrm{.}30$ grams of HCI $($molar mass $=36\mathrm{.}5\frac{g}{m}ol?$

$Zn+2$HCI $ZnC{l}_2+H_2$

a$.6\mathrm{.}82g$

b$.12\mathrm{.}27g$

c$.2\mathrm{.}00g$

d$.6\mathrm{.}13g$

e$.1\mathrm{.}12g$