Question

How much H2O is produced when 30000 g of C2H2 burns completely? Answer in units of g.

Answer 1

1) First write a balanced chemical equation

`2\ C_(2) H_(2)_((g))` +
`5\ O_(2)_((g))` --->
`4\ CO_(2)_((g))` +
`2\ H_(2)O_((g))`

2) Use dimensional analysis to find your answer.

= 30000g
`C_(2) H_(2)` ×
`(1\ mol\ C_(2)H_(2))/(26.04g\ C_(2)H_(2))` ×
`(2\ mol\ H_(2)O)/(2\ mol\ C_(2)H_(2))` ×
`(18.02g\ H_(2)O)/(1\ mol\ H_(2)O)`

= 20760.36866

= 20760g H₂O