Chlorine has an atomic number of 17. it often forms an ion by gaining 1 electron. what would its charge be?

The charge would be -1.

Explanation:

The atomic number refers to the number of protons an atom has. Chlorine is electrically neutral, so it has the same  number of positive charges (protons) than negative charges (electrons). Therefore, chlorine has 17 protons and 17 electrons. When it gains 1 electron, it will have an excess of one negative charge, so the charge of the ion will be -1, forming Cl⁻.

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o