Question

Using this balanced equation in order to produce 7 moles of oxygen gas, how many moles of water would you need to start with? 2H2O -- > 2H2 + O2.

Answer 1

You would need `14color(white)(l)mol` of `H_2O`.

Explanation:

`2H_2O->2H_2+O_2`

This means that for every one mole of diatomic oxygen produced, 2 moles of water is required.

`(7color(white)(l)molcolor(white)(l)O_2)/1*(2color(white)(l)molcolor(white)(l)H_2O)/(1color(white)(l)molcolor(white)(l)O_2)`

`molcolor(white)(l)O_2` cancel:

`(7cancel(color(white)(l)molcolor(white)(l)O_2))/1*(2color(white)(l)molcolor(white)(l)H_2O)/(1color(white)(l)cancel(molcolor(white)(l)O_2))=14color(white)(l)molcolor(white)(l)H_2O`