To get the molarity, you divide the moles of solute by the litres of solution.
Molarity
=
moles of solute
litres of solution
For example, a 0.25 mol/L NaOH solution contains 0.25 mol of sodium hydroxide in every litre of solution.
To calculate the molarity of a solution, you need to know the number of moles of solute and the total volume of the solution.
To calculate molarity:
Calculate the number of moles of solute present.
Calculate the number of litres of solution present.
Divide the number of moles of solute by the number of litres of solution.
Answer:
4,1,5,3,2 (from left to right)
As has an atomic number of 33, so it has 33 protons.
It has a charge of 3-, so there are three more electrons than protons. Thus, there are 36 electrons.
It has a mass of 75, which is the sum of neutrons and protons.
33+n=75 ---> n = 75 - 33 = 42 neutrons
The answer is e) 33 protons, 42 neutrons and 36 electrons.