Copper II Sulfide is formed when copper and sulfur are heated together. In this reaction, 172 g of copper reacts with 58 g of sulfur. After the reaction is complete, 19 g of sulfur still remains unreacted. What is the mass of copper sulfide formed?

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.

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8