12 as there a 12 present in this balanced equation.
Answer:
C
Explanation:
The ozone layer absorbs ultraviolet rays from the sun.
<span>88 and 84 are mass numbers
the mass number of an element is the sum of the number of protons and the number of neutrons (in which they are each equal to 1 unit (amu))
the number of protons is always the same for a given element (e.g. any C atom has 6 protons), but the number of neutrons varies. Two atoms of the same element (number of protons) with a different number of neutrons are called "isotopes".
So the two strontium atoms differ by 4 neutrons. 84Sr has four neutrons less than 88Sr</span>
All tropical cyclones can produce widespread torrential rains, which cause massive flooding and trigger landslides and debris flows.
A magnesium atom is a neutral atom where the number of protons and electrons are the same. A magnesium ion has a positve 2 charge since it will lose two of its electrons when it undergoes ionic bonding. Since it's the same element it will still have the same amount of 12 protons. For isotopes of magnesium, they will have differing amounts of neutrons and thus a difference in the mass number since neutrons have a mass of about 1