What makes an acid or a base

Answer Key - Grade 10 Science Worksheet

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

1. 1.

   Acetic acid, CH₃COOH, has 4 hydrogen atoms and gives up one H⁺. How many hydrogen atoms does its conjugate base have, Ari?

   3 H atoms
2. 2.

   Citric acid, C₆H₈O₇, has 8 hydrogen atoms and gives up one H⁺. How many hydrogen atoms does its first conjugate base have, Bo?

   7 H atoms
3. 3.

   Sulfuric acid, H₂SO₄, has 2 hydrogen atoms and gives up one H⁺. How many hydrogen atoms does HSO₄⁻, its conjugate base, have, Esme?

   1 H atoms
4. 4.

   In the Brønsted–Lowry model, what is an acid, Jun?

   • A proton acceptor
   • An OH⁻ donor
   • A proton donor
5. 5.

   In HCl + H₂O → H₃O⁺ + Cl⁻, which reactant accepts the proton, Kira?

   • H₂O
   • Neither reactant
   • HCl
6. 6.

   What is the conjugate base of acetic acid, CH₃COOH, Milo?

   • OH⁻
   • CH₃COOH₂⁺
   • CH₃COO⁻
7. 7.

   What is the conjugate acid of ammonia, NH₃, Noah?

   • NH₂⁻
   • NH₄⁺
   • H₃O⁺
8. 8.

   In HCl + H₂O → H₃O⁺ + Cl⁻, which two form a conjugate acid-base pair, Pia?

   • HCl and Cl⁻
   • HCl and H₂O
   • Cl⁻ and H₃O⁺
9. 9.

   Milk of magnesia is mostly Mg(OH)₂. Why does it count as an Arrhenius base, Ren?

   • It gives OH⁻ ions in water
   • Its Mg²⁺ ions donate protons
   • It has no hydrogen atoms in it
10. 10.

    Ammonia, NH₃, has no OH⁻ in its formula. Why is it still a base, Tala?

    • It accepts a proton from water
    • It donates a proton to water
    • It gives off H⁺ in water