Answer:
A. 35Cl1-
Explanation:
Chlorine needs 1 more electron to have full octet thus will take 1 electron and possess a -1 charge.
Remark
The given thing on the right is a positron. The mass for these subatomic particles is considered to be 0. It's atomic number is 1 which means it is a blood relative of a proton.
So essentially what happens is that X is one space to the left on the periodic table. But let's solve this a little bit more formally.
Solution

y stays the same at 147. It is z that changes.
65 = z + 1 Subtract 1 from both sides.
64 = z
So the chemical with 64 as its position on the periodic table is
Gadolinium and the answer is C
One type of chemical process that can be either exothermic or endothermic is dissolving of salts in water. A salt is a compound made up of positively charged ions and negatively charged ions which are held together in a solid state because the positive and negative charges attract one another.
Water is constantly being cycled between the atmosphere, the ocean and land. This cycling is a very important process that helps sustain life on Earth. As the water evaporates, vapors rise, and condense into clouds. The clouds move over land, and precipitation falls in the form of rain, ice, or snow.