Strong and weak acids and bases

Answer Key - Grade 10 Science Worksheet - Building Confidence

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

1. 1.

   A model drawing of acetic acid shows 40 molecules; 1 of them split into ions. What percent split, Ari?

   2.5 %
2. 2.

   A model drawing of acetic acid shows 80 molecules; 1 of them split into ions. What percent split, Bo?

   1.25 %
3. 3.

   A model drawing of acetic acid shows 200 molecules; 3 of them split into ions. What percent split, Esme?

   1.5 %
5. 4.

   Using the drawings, which acid is weak, Jun?

   • Acetic acid
   • Nitric acid
   • Hydrochloric acid
6. 5.

   Using the drawings, what makes HCl a strong acid, Kira?

   Use the picture in question 4.

   • Its smell is stronger than others
   • It is a very concentrated acid
   • Its molecules all split into ions
7. 6.

   Which of these acids is strong, Milo?

   • Citric acid
   • Hydrochloric acid
   • Acetic acid
8. 7.

   Vinegar's acid is acetic acid. Is acetic acid strong or weak, Pia?

   • Strong: it splits completely
   • Strong: vinegar tastes sour
   • Weak: it splits partly
9. 8.

   Which arrow fits a weak acid splitting in water, Ren?

   • ⇌, both ways
   • ←, backward
   • →, forward and complete
10. 9.

    HCl → H⁺ + Cl⁻ is written with a one-way arrow. Why, Tala?

    • HCl stays as whole molecules
    • HCl ionizes completely
    • Cl⁻ is a strong base
11. 10.

    Which particles are mostly present in hydrochloric acid, Zee?

    • OH⁻ and Na⁺ ions
    • Whole HCl molecules
    • H₃O⁺ and Cl⁻ ions