4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution. Calculate the concentration of this copper sulfate solution in g dm⁻³. (2) (b) Sodium hydroxide solution was added to a solution of copper sulfate. A precipitate of copper hydroxide and a solution of sodium sulfate were formed. (i) State what would be seen in the reaction. (1) (ii) Complete the balanced equation for the reaction by adding a number in front of NaOH. (1) NaOH + CuSO₄ → Cu(OH)₂ + Na₂SO₄ (iii) Describe how to obtain a pure, dry sample of the precipitate of copper hydroxide from the reaction mixture. (3)

GCSE Edexcel Chemistry Combined Science Titrations: 4. (a) 3.14g of solid copper sul

4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1

Question 4

4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution. Calculate the concentration of this copper sulfate solution in g dm⁻... show full transcript

Worked Solution & Example Answer:4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1

Step 1

Calculate the concentration of this copper sulfate solution in g dm⁻³.

96%

114 rated

Answer

To find the concentration, we use the formula:

$\text{concentration (g dm}^{-3}\text{)} = \frac{\text{mass of solid (g)}}{\text{volume of solution (dm}^3\text{)}}$

Given that the mass of copper sulfate is 3.14 g and the volume is 250 cm³, we convert the volume into dm³:

$250 \text{ cm}^3 = 0.250 \text{ dm}^3$

Now, substituting the values:

$\text{concentration} = \frac{3.14}{0.250} = 12.56 \text{ g dm}^{-3}$

Step 2

State what would be seen in the reaction.

99%

104 rated

Answer

During the reaction, a blue precipitate of copper hydroxide would be seen forming in the solution.

Step 3

Complete the balanced equation for the reaction by adding a number in front of NaOH.

96%

101 rated

Answer

The balanced equation is:

$2 \text{NaOH} + \text{CuSO}_4 \rightarrow \text{Cu(OH)}_2 + \text{Na}_2\text{SO}_4$

Step 4

Describe how to obtain a pure, dry sample of the precipitate of copper hydroxide from the reaction mixture.

98%

120 rated

Answer

To obtain a pure, dry sample of copper hydroxide, follow these steps:

Filter the reaction mixture to separate the copper hydroxide precipitate from the liquid.
Wash the residue gently with distilled water to remove impurities.
Allow the filter paper containing the precipitate to dry in a warm place or use a warm Bunsen burner to evaporate any remaining water, ensuring not to overheat.

4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1

Worked Solution & Example Answer:4. (a) 3.14g of solid copper sulfate was dissolved in water and made up to 250 cm³ of solution - Edexcel - GCSE Chemistry Combined Science - Question 4 - 2022 - Paper 1

Calculate the concentration of this copper sulfate solution in g dm⁻³.

State what would be seen in the reaction.

Complete the balanced equation for the reaction by adding a number in front of NaOH.

Describe how to obtain a pure, dry sample of the precipitate of copper hydroxide from the reaction mixture.

Join the GCSE students using SimpleStudy...