Question

the single displacement reaction K + NaCl ----> Na + KCl

Determine how many grams of sodium will be produced when 20g of K is reacted with an excess of NaCl

Answer 1

The conversion sequence is;

$gK\to mol K\to molNa\to gNa$

Conversion of mass to moles:

$20gK\times$ $1mol K\over 39.0983K$ $=0.5115mol K$

Moles to moles conversion( using the mole ratio):

$0.5115mol K\times$ $1mol Na\over 1mol K$ $=0.5115mol Na$

Moles to mass(g) conversion:

$0.5115mol Na$ $\times$ $22.9897mol Na\over1mol K$ $=11.7592gNa$

The mass of Na produced is $11.7592g$