i cant do this home work. i REALLY suck at physics, this is why im here. can someone help me pleasse??? :) 1#to combust completely 7g of iron, 2L of oxygen is needed. for each of the following state if any unreacred iron rests after combustion and if it does how much: a) 2g of iron and 500mL of oxygen b) 1g of iron and 300mL of oxygen c) 1.75g of iron and 500mL oxygen 2# there exists two oxides of copper. Copper (I) oxide - Cu2O, and copper (II) ocide - CuO. calculate the % of copper atoms in each.