Before Start - Rewview
- Solute is the chemical that has the smaller quantity.
- Solvent is the chemical that has the larger quantity.
Molar Concentration(Molarity)
- is the number of moles of solute in a specific mount of litre of a solution.
- We use "M" or "mole/L" to denote molarity.
Molarity = moles of solute(mol) / volume of solution(L)
e.g. If there is 3.40 moles of NaCl in 1.2 litres of solution, what is the molar concentration?
Molarity = moles of solute(mol) / volume of solution(L)
= 3.40 moles of NaCl / 1.2L
= 2.8333333...
= 2.8 mol/L NaCl or 2.8 M
e.g. Calculate the molarity of a solution that has 0.738 moles NaOH in 2.40L of solution.
Molarity = mol / L M of NaOH = 0.738 mol NaOH / 2.40 L
= 0.3075
= 0.308 M NaOH or 0.308 mol/L NaOH
e.g. How many moles of KCl are contained in 1.5 L of 2.00 mol/L KCl?
moles KCl = molarity × volume
= 2.00 mol/L × 1.5L
= 3.0 moles KCl
e.g. What volume of 0.34 mol/L NaCl do we must take to obtain 0.021 mole of NaCl?
volume = moles / molarity
= 0.34 mole NaCl / 0.021 mol/L NaCl
= 16 L
And here is very interesting video for fun learnig.
http://www.youtube.com/watch?v=WsQk8C098zA
