How many moles is 4.50 X 1021 molecules of copper (Cu)? 0.0075 mol , 6.02 X 1023 mol ,286 mol an 2.86 x 1023 mol​

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

what's the