Find a concentration from a titration

Answer Key - Grade 10 Science Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   A described curve for 20 mL of H₂SO₄ jumps at 16 mL of 0.25 M NaOH: H₂SO₄ + 2 NaOH → Na₂SO₄ + 2 H₂O. What is the H₂SO₄ concentration, Bo?

   0.1 M
2. 2.

   A described curve for 10 mL of H₂SO₄ jumps at 24 mL of 0.15 M NaOH: H₂SO₄ + 2 NaOH → Na₂SO₄ + 2 H₂O. What is the H₂SO₄ concentration, Esme?

   0.18 M
3. 3.

   The jump is read 1 mL past its true place. Is the acid concentration found too high or too low, Kira?

   • Too low
   • Exactly right
   • Too high
4. 4.

   In OpenStax's example, 25.00 mL of HCl needs 25.00 mL of 0.100 M NaOH. What is the HCl concentration, Luz?

   • 2.5 M
   • 0.100 M
   • 0.0025 M
5. 5.

   Milo says the equivalence point is where equal volumes of acid and base have mixed. Agree or disagree?

   • Agree: the pH there is 1
   • Disagree: equal moles, not volumes
   • Agree: the two volumes must match up
6. 6.

   Noah says 20.0 mL of 0.10 M HCl always needs 20.0 mL of NaOH, whatever the NaOH concentration. Agree or disagree?

   • Agree: equal volumes of acid and base are needed
   • Agree: NaOH comes as 0.10 M
   • Disagree: it depends on NaOH's molarity
7. 7.

   Pia says 1 mol of H₂SO₄ needs the same moles of NaOH as 1 mol of HCl. Agree or disagree?

   • Agree: sulfuric acid is weaker
   • Disagree: it needs twice as many
   • Agree: any acid needs the same
8. 8.

   Using OpenStax's curve, 12.5 mL of NaOH has been added out of the 25.0 mL needed. How much of the HCl is left, Ren?

   • Nothing is left
   • Half
   • A quarter
9. 9.

   25.0 mL of HCl reaches equivalence with 25.0 mL of NaOH. What is the total volume then, Tala?

   • 50.0 mL
   • 25.0 mL
   • 625 mL
10. 10.

    A titration uses up 0.0025 mol of HCl with NaOH. How much NaCl forms, Zee?

    • 0.00125 mol
    • 0.0025 mol
    • 0.005 mol