First, we must find the total mass of CuBr₂:
Mass = 64 + 2 x 80
Mass = 224
Percentage mass of copper = mass of copper x 100 / total mass
Percentage mass of copper = (64 / 224) x 100
Percentage mass of copper = 28.45%
I assume this is a true or false question. I would say true
Answer: Nitrogen
Explanation: Nitrogen has an atomic number of 7 and an atomic mass of about 14 u
<span>FeCl3+ H2O --> Fe(OH)3 + 3 HCl the reaction will cause the least temprature change</span>