Mass number= atomic number + number of neutrons.
A=Z+N
Z=number of protons=12
N=12
A=12+12=24
If, we have 12 protons and 10 electrons, the charge of this ion is +2
Therefore: mass number:24; charge: +2
Answer: a. mass number: 24; charge: +2
Answer:
The pH of the sweater containing Hydrogen ion concentration
is
<u>8</u>
<u></u>
Explanation:
pH = It is the negative logarithm of activity (concentration) of hydrogen ions.
pH = -log([H+])
Now, In the question the concentration of [H+] ions is :
![[H^{+}]=1\times 10^{-8}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%3D1%5Ctimes%2010%5E%7B-8%7D)

use the relation:


pH = 8
Note : <em><u> 1 times 10 to the power of 8 must be" 1 times 10 to the power of -8"</u></em>
If the concentration is
![[H^{+}]=1\times 10^{8}](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%3D1%5Ctimes%2010%5E%7B8%7D)
Then pH = -8 , which is not possible . So in that case the pH calculation is by other method
Neon is an element and elements are pure oxygen is. Or it is a gas
<span>When a chemical reaction occurs and the thermometer in the container records a drop in temperature t</span>he reaction is exothermic because heat was released by the reaction.
<span>B. The reaction is exothermic because heat was released by the reaction. is your answer.
Hoped I helped!</span>
Answer : Any natural sources of CFC's are not known only the major sources like aerosols, propellants, refrigerants,etc are known. So, if any natural sources are given then it cannot be called as a major source for emitting CFC into environment.