The drain cleaner, Drainex contains small bits of aluminium which react with caustic soda to produce dihydrogen. What volume of dihydrogen at `20^(@)C` and 1 bar will be released when 0.15 g aluminium reacts?

Explanation

The following reaction involving aluminium (Al) and caustic soda (NaOH) produce `H_(2)` gas:
`2Al(s)+2NaOH(aq)+2H_(2)O(l) to 2NaAlO_(2)(aq)+3H_(2)(g) 3xx1mol`
According to this reaction 54g of `Al-=3 mol ` of `H_(2)`
`therefore 0.15g` of `Al-=(3)/(54)xx0.15-=8.33xx10^(-3)mol` of `H_(2)`
to calculate volume of the liberated `H_(2)` gas, we apply the ideal gas equation, PV=nRT.
The number of moles of liberated `H_(2)` gas `(n)=8.33xx10^(-3)mol`
`therefore V=(nRT)/(P)=(8.33xx10^(-3)xx0.0821xx293)/(0.987)L=0.203L=203mL`