Concentration Calculations

• What is the unit for concentration in this context?

  mol/dm³
• What is the first step to calculate concentration?

  Find the concentration in mol/dm³
• How much sodium hydroxide was used to neutralize the sulfuric acid?

  25.0 cm³
• What is the balanced equation for the reaction between NaOH and H₂SO₄?

  2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
• How do you calculate the number of moles of NaOH?

  Use volume and concentration formula
• How many moles of NaOH are present in 25.0 cm³ of 0.100 mol/dm³ solution?

  0.00250 moles
• How do you find the moles of sulfuric acid from the moles of NaOH?

  Divide moles of NaOH by 2
• How many moles of H₂SO₄ reacted with 0.00250 moles of NaOH?

  0.00125 moles
• What is the formula to calculate concentration?

  Concentration = number of moles ÷ volume
• What is the concentration of H₂SO₄ in mol/dm³?

  0.0417 mol/dm³
• What is the relative formula mass of sulfuric acid (H₂SO₄)?

  98
• How do you convert concentration from mol/dm³ to g/dm³?

  Use mass = moles x M
• What is the mass in grams of 0.041666... moles of H₂SO₄?

  4.08 g
• What is the concentration of sulfuric acid in g/dm³?

  4.08 g/dm³
• What are the steps to calculate concentration in mol/dm³?

  1. Calculate moles of known substance.
  2. Use the balanced equation to find moles of unknown.
  3. Calculate concentration using moles and volume.
• How do you convert concentration from mol/dm³ to g/dm³?

  1. Find concentration in mol/dm³.
  2. Calculate mass using mass = moles x M.
• What is the significance of the balanced equation in concentration calculations?

  • Determines mole ratios of reactants.
  • Essential for calculating unknown concentrations.
• How would you calculate the concentration of a solution containing 0.6 g of salt in 15 cm³?

  1. Convert 15 cm³ to dm³.
  2. Use concentration formula: concentration = mass/volume.