Each isotope of Oxygen has a different number of neutrons
<h3>Further explanation
</h3>
The elements in nature have several types of isotopes
Atomic mass is the average atomic mass of all its isotopes
Isotopes are atoms has the same number of protons but has a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Some of the isotopes of oxygen are:

Each isotope has 8 protons and 8 electrons but has a different number of neutrons
For O-16: number of neutrons = 16-8 = 8
For O-17: number of neutrons = 17-8 = 9
For O-18: number of neutrons = 18-8 = 10
<span>The term used by meteorologists for predicting the we ather is </span>forecasting
We are given
0.2 M HCHO2 which is formic acid, a weak acid
and
0.15 M NaCHO2 which is a salt which can be formed by reacting HCHO2 and NaOH
The mixture of the two results to a basic buffer solution
To get the pH of a base buffer, we use the formula
pH = 14 - pOH = 14 - (pKa - log [salt]/[base])
We need the pKa of HCO2
From, literature, pKa = 1.77 x 10^-4
Substituting into the equation
pH = 14 - (1.77 x 10^-4 - log 0.15/0.2)
pH = 13.87
So, the pH of the buffer solution is 13.87
A pH of greater than 7 indicates that the solution is basic and a pH close to 14 indicates high alkalinity. This is due to the buffering effect of the salt on the base.
H₂ is the limiting reactant.
<u>Explanation:</u>
H₂ reacts with O₂
The reaction would be
2H₂ + O₂ → 2H₂O
According to the balanced equation, 2 moles of H₂ reacts with 1 mole of O₂ to form 2 moles of H₂O.
The ratio of usage of H₂ and O₂ is 2 : 1 respectively
If 3 moles of H₂ and 2 moles of O₂ are present then:
3 moles of H₂ would require 1.5 moles of O₂ ( 2 : 1 of H₂ and O₂ )
Out of 2 moles of O₂, 1.5 moles would be used and 0.5 mole would be in excess.
Therefore, H₂ is the limiting reactant as the number of moles of H₂ are not enough to use all the O₂.