The answers would be the mass before a reaction is the same as the mass after a reaction which basically means mass is conserved
The question above is simply asking us to convert the value from calories into kilojoules. Therefore, we need some factor to multiply to be able to convert it to such units. For calories to kJ, the factor would be 4.184.
2700 cal ( 4.184 kJ/cal) = 11296.8 kJ
Answer:
Cu(s) + N₂(g) + 2O₂(g) ⟶ Cu(NO₂)₂(s)
The mass number goes on top, and the atomic number goes on bottom.
Therefore, the answer is C:
40
K
19
