Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
221–230 of 407 · Easy
Question 221
2 marks · Easy
Answer and see the solution →Nitric acid reacts with sodium carbonate according to the following equation:
Calculate the minimum volume, in cm³, of 0.250 mol/dm³ nitric acid solution needed to completely react with 25.0 cm³ of 0.100 mol/dm³ sodium carbonate solution.
Question 222
5 marks · Easy
Answer and see the solution →Ammonia gas is produced by the reaction of hydrogen gas with nitrogen gas at room temperature and pressure (rtp).
(a)[1 mark]State the balanced chemical equation for the formation of ammonia from hydrogen and nitrogen.
(b)[1 mark]What is the volume of 2 moles of hydrogen gas at rtp? Give your answer in dm³.
(c)[1 mark]Convert your answer to part (b) into cm³.
(d)[1 mark]If 1 mole of nitrogen gas reacts completely, how many moles of hydrogen gas are needed?
(e)[1 mark]Calculate the total volume (in dm³) of all gases present after the complete reaction of 1 dm³ nitrogen gas with excess hydrogen gas at rtp. (State your assumptions about volumes in your answer.)
Question 223
5 marks · Easy
Answer and see the solution →A student investigates the reaction between barium hydroxide and sulfuric acid:
(a)[2 marks]Calculate the number of moles of barium hydroxide in 40.0 cm³ of 0.200 mol/dm³ barium hydroxide solution.
(b)[3 marks]During a titration, 25.0 cm³ of the barium hydroxide solution from part (a) is neutralised by 19.5 cm³ of sulfuric acid solution.
Calculate the concentration of the sulfuric acid in mol/dm³. Show your working.
Question 224
5 marks · Easy
Answer and see the solution →Zinc sulfate solution reacts with barium chloride solution: \[ \ce{ZnSO4(aq) + BaCl2(aq) -> BaSO4(s) + ZnCl2(aq)} \] A titration is carried out to determine the amount of barium chloride solution required to completely react with a given volume of zinc sulfate solution.
(a)[1 mark]Write the mole ratio of zinc sulfate to barium chloride in the balanced chemical equation.
(b)[1 mark]In a titration, 30.0 cm³ of 0.150 mol/dm³ zinc sulfate solution reacts exactly with 30.0 cm³ of barium chloride solution. Calculate the number of moles of zinc sulfate used.
(c)[1 mark]Using your answers from (a) and (b), calculate the number of moles of barium chloride that react.
(d)[2 marks]Calculate the concentration (in mol/dm³) of the barium chloride solution.
Question 225
1 mark · Easy
Answer and see the solution →What type of force holds the magnesium ions and oxide ions together in magnesium oxide?
Question 226
3 marks · Easy
Answer and see the solution →For the ionic compound magnesium oxide (MgO):
(a)[1 mark]State the charge of a magnesium ion.
(b)[1 mark]What is the charge on an oxide ion?
(c)[1 mark]Name the type of ion formed by magnesium.
Question 227
2 marks · Easy
Answer and see the solution →Draw a dot-and-cross diagram to show the electron arrangement in the Mg^{2+} ion. Use dots for magnesium's original electrons. Clearly show the charge.
Question 228
2 marks · Easy
Answer and see the solution →Explain why magnesium oxide has a high melting point. Use your knowledge of ionic bonding in your answer.
Question 229
3 marks · Easy
Answer and see the solution →The table shows the number of electrons in neutral atoms and the corresponding ions for magnesium and oxygen.
Particle Number of electrons Mg atom 12 Mg^{2+} ion O atom 8 O^{2-} ion (a)[2 marks]Complete the table by filling in the missing numbers for the ions.
(b)[1 mark]Explain, in terms of electron transfer, how these ions form.
Question 230
1 mark · Easy
Answer and see the solution →How many electrons are in the outer shell of an oxide ion (O^{2-})?