How many grams of nitrogen monoxide gas can be produced from 80.0 ml of 4.00 M HNO3 and excess Cu?
3Cu(s)+ 8Hno3(aq)-> 3Cu(NO3)2(aq)+4H2O(/)+2NO(g)
Here is a worked example. Just follow the steps. Post you work if you get stuck.
http://www.jiskha.com/science/chemistry/stoichiometry.html