5.3.3 Concentration of Solutions

• What does the concentration of a solution measure?

  Amount of solute per volume
• Concentration is typically expressed in moles per litre ($\text{mol dm}^{ - 3}$) or grams per litre
• If 2 moles of NaCl are dissolved in 1 litre of water, the concentration is $2 \text{ mol dm}^{ - 3}$
• In what two units is concentration typically expressed?

  mol/dm³ and g/dm³
• A sample of water containing 0.01 grams of nitrate per 1000 grams of water has a concentration of 10 ppm
• What is the formula to convert mol/dm³ to g/dm³?

  $C_{\text{g / dm}^{3}} =$$C_{\text{mol / dm}^{3}} \times M$
• To convert 2 mol/dm³ of NaCl to g/dm³, you multiply by the molar mass of NaCl.
• What is the concentration in g/dm³ of a 2 mol/dm³ NaCl solution?

  116.88 g/dm³
• Steps to convert mol/dm³ to g/dm³

  1️⃣ Identify the concentration in mol/dm³

  2️⃣ Find the molar mass of the solute

  3️⃣ Use the formula: $C_{\text{g / dm}^{3}} =$$C_{\text{mol / dm}^{3}} \times M$

  4️⃣ Calculate the concentration in g/dm³
• The formula to convert mol/dm³ to g/dm³ is \text{Concentration \in g / dm}^{3} = \text{Concentration \in mol / dm}^{3} \times \text{Molar mass of }solute
• What is the molar mass of NaCl?

  58.44 g/mol
• What formula is used to convert mol/dm³ to g/dm³?

  $C =$$n \times M$
• The molar mass is used to convert between grams and moles in concentration units.
• Converting between mol/dm³ and g/dm³ is essential in chemistry
• The formula to convert mol/dm³ to g/dm³ is \text{Concentration \in g / dm}^{3} = \text{Concentration \in mol / dm}^{3} \times \text{Molar mass of solute}</latex>
• The molar mass of NaCl is 58.44 g/mol.
• This conversion uses the molar mass to switch between moles and grams in concentration units.
• The formula to calculate concentration from moles and volume is $C =$$\frac{n}{V}$
• In the formula $C =$$\frac{n}{V}$, n represents the number of moles.
• To calculate the number of moles using concentration and volume, the formula is $n =$$CV$, where C is concentration and V is volume.
• The formula to calculate volume from concentration and moles is $V =$$\frac{n}{C}$
• The concentration of a solution is a measure of the amount of solute dissolved in a specific volume of solvent.
• A solution containing 2 moles of NaCl in 1 litre of water has a concentration of 2 mol/dm³.
• Match the concentration unit with its corresponding formula:

  mol/dm³ ↔️ $C =$$\frac{n}{V}$

  g/dm³ ↔️ $C =$$\frac{m}{V}$
• To calculate the concentration of a solution, the volume must be in litres.
• What is the formula to calculate the concentration of a solution?

  $C =$$\frac{n}{V}$
• For 0.5 moles of glucose in 2 litres of water, the concentration is 0.25
• The formula to calculate the number of moles is $n =$$CV$
• In a solution with a concentration of 1.5 mol/L and a volume of 0.75 L, the number of moles is 1.125
• What is the formula to calculate the volume of a solution?

  $V =$$\frac{n}{C}$
• The dilution equation is C_{1}V_{1} = C_{2}V_{2}</latex>
• Diluting 0.5 L of 1 mol/L NaOH to 0.1 mol/L requires a final volume of 5
• What is the formula used in titrations to calculate concentrations?

  $C_{1}V_{1} =$$C_{2}V_{2}$
• The concentration of NaOH in the titration example is 0.08 M