How many moles of NO must react to form 5 moles of NO2 ?

2NO + O2 -> 2NO2

According to the balanced chemical equation, 2 moles of NO react to form 2 moles of NO2.

Therefore, 2 moles of NO would react to form 2 moles of NO2.

To find out how many moles of NO are needed to produce 5 moles of NO2, we can use a proportion:

2 moles of NO/2 moles of NO2 = x moles of NO/5 moles of NO2

Simplifying the proportion:

1 mole of NO / 1 mole of NO2 = x moles of NO / 5 moles of NO2

Cross multiply:

1 * 5 = 1 * x

5 = x

Therefore, 5 moles of NO must react to form 5 moles of NO2.