Double replacement and solubility rules

Answer Key - Grade 10 Science Worksheet - Building Confidence

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

1. 1.

   In CaCl₂ + Na₂CO₃ → CaCO₃ + 2 NaCl, 5 units of white CaCO₃ form. How many NaCl units form, Bo?

   10 NaCl units

2. Read this first

   Use this

   Short solubility table (OpenStax Chemistry 2e, Table 4.1, shortened). Columns: ions, usually, exceptions. Na⁺, K⁺, NH₄⁺ (group 1 and ammonium), soluble, none; NO₃⁻ (nitrate), soluble, none; Cl⁻, Br⁻, I⁻, soluble, Ag⁺ and a few others; SO₄²⁻ (sulfate), soluble, Ag⁺, Ca²⁺ and a few others; CO₃²⁻, PO₄³⁻, insoluble, group 1 and NH₄⁺; OH⁻ (hydroxide), insoluble, group 1 and one other.

3. 2.

   Using the table, does NaNO₃ dissolve in water, Jun?

   • No: it contains oxygen
   • No: sodium compounds sink
   • Yes: nitrates are soluble
4. 3.

   Using the table, which compound is insoluble, Kira?

   • NaCl
   • AgCl
   • KCl
5. 4.

   Using the table, which carbonate dissolves in water, Luz?

   • MgCO₃
   • CaCO₃
   • Na₂CO₃
6. 5.

   In an equation, what does (s) after a product mean, Milo?

   • It bubbles off as a gas
   • It forms as a solid
   • It stays dissolved
7. 6.

   In an equation, what does (aq) after a formula mean, Noah?

   • A solid that sinks
   • Dissolved in water
   • A pure liquid
8. 7.

   What is a precipitate, Pia?

   • A liquid that won't mix
   • A gas bubbling out of a liquid
   • A solid that forms from solutions
9. 8.

   In AgNO₃ + NaCl → AgCl + NaNO₃, which product is the white solid, Ren?

   • NaNO₃
   • AgCl
   • Neither product
10. 9.

    In CaCl₂ + Na₂CO₃ → CaCO₃ + 2 NaCl, which product is the white solid, Tala?

    • NaCl
    • CaCO₃
    • Both products
11. 10.

    In CuSO₄ + 2 NaOH → Cu(OH)₂ + Na₂SO₄, which product is the blue solid, Zee?

    • Neither product
    • Na₂SO₄
    • Cu(OH)₂