Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Inorganic Chemistry
869 practice questions
Topics covered
- The Alkali Metals85 practice questions
- The Halogens86 practice questions
- Gases in the Atmosphere86 practice questions
- Reactivity Series163 practice questions
- Extraction and Uses of Metals128 practice questions
- Acids, Alkalis and Titrations83 practice questions
- Acids, Bases and Salt Preparations156 practice questions
- Chemical Tests68 practice questions
Practice questions
241–250 of 359 · Easy
Question 241
3 marks · Easy
Answer and see the solution →Potassium carbonate ([32mK_2CO_3[0m) can make water alkaline without containing hydroxide ions in its formula.
(a)[1 mark]Write the formula of the ion that makes a solution alkaline.
(b)[2 marks]Explain, using a chemical equation, how potassium carbonate forms an alkaline solution in water.
Question 242
2 marks · Easy
Answer and see the solution →Magnesium hydroxide ([32mMg(OH)_2[0m) is often used as an antacid. It does not dissolve well in water, but any dissolved part is alkaline. Explain why a solution of magnesium hydroxide is alkaline.
Question 243
1 mark · Easy
Answer and see the solution →Name a substance, other than ammonia, that forms an alkaline solution when dissolved in water.
Question 244
3 marks · Easy
Answer and see the solution →Read the passage and answer the questions below. Acids release hydrogen ions ([32mH^+[0m) in water, making the solution acidic.
(a)[1 mark]Name the ion formed in solution when hydrochloric acid is added to water.
(b)[1 mark]Give the symbol for this ion.
(c)[1 mark]Explain, using the equation, what happens when [32mHCl[0m is dissolved in water.
Question 245
3 marks · Easy
Answer and see the solution →The following table shows the formulae of several acids. Use the table to answer the questions below.
Table 1. Some common acids and their formulae. Acid Formula Hydrochloric acid HCl Nitric acid HNO₃ Sulfuric acid H₂SO₄ Phosphoric acid H₃PO₄ Ethanoic acid CH₃COOH (a)[1 mark]Identify the ion that all acids in the table produce when dissolved in water.
(b)[1 mark]State the chemical symbol and charge of this ion.
(c)[1 mark]Explain, using the formulae in the table, how you know that each acid can form this ion.
Question 246
2 marks · Easy
Answer and see the solution →A student dissolves 0.20 mol of sodium carbonate (Na_2CO_3) in enough water to make 1.0 dm³ of solution. Sodium carbonate forms an alkaline solution because it reacts to produce hydroxide ions.
Calculate the concentration of carbonate ions (CO_3^{2-}) present in the solution. Give your answer in mol/dm³.
Question 247
1 mark · Easy
Answer and see the solution →Name the piece of apparatus used to deliver small, measured volumes of acid into a conical flask during a titration.
Question 248
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the colour change you would see when phenolphthalein is used as the indicator and the alkali in the conical flask is just neutralised by the acid from the burette.
(b)[1 mark]Give one reason why phenolphthalein is preferred over universal indicator for titrations.
(c)[1 mark]Name the flask used to hold the solution during a titration.
Question 249
2 marks · Easy
Answer and see the solution →During a titration, a student records an initial burette reading of 6.40 cm³ and a final reading of 28.15 cm³. Calculate the volume of solution delivered from the burette.
Question 250
2 marks · Easy
Answer and see the solution →Explain why titration readings should be recorded to two decimal places.