Question

Please help and show me how to get the answer

Answer 1

It may be ethier 1, 3, or 4. When I did it the closest answer I got was 5.62 which is close to 1 but I am not sure.

What I did was I used 253g and I divided the mass of Cu and NO (253/ 63=4 moles for 3Cu and 253/30= 8 moles of 2NO) Then I did bigger over smaller for moles (8/4) and then I multiplied it towards the 253. But unfortunately I forgot what to do after that so you ethier divide it by 30(mass of NO, divide it by 2(8/4=2) or divide it by 1 (looking for 1 of NO)