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
391–400 of 991
Question 391
2 marks · Normal
Answer and see the solution →Write the balanced chemical equation, including state symbols, for the reaction between sodium hydroxide solution and hydrochloric acid when they form sodium chloride solution and water.
Question 392
4 marks · Normal
Answer and see the solution →Answer the questions about the compound sodium sulfate, Na2SO4.
(a)[1 mark]State the relative atomic masses (Ar) of sodium (Na), sulfur (S), and oxygen (O).
(b)[2 marks]Calculate the relative formula mass (Mr) of sodium sulfate, Na2SO4.
(c)[1 mark]State the Mr of Na2SO4 to 1 decimal place.
Question 393
3 marks · Normal
Answer and see the solution →A student has 21 g of magnesium chloride (MgCl2). Calculate the number of moles of MgCl2 present.
(Ar: Mg = 24, Cl = 35.5)
Question 394
3 marks · Normal
Answer and see the solution →The equation for a reaction is:
A student reacts 27.0 g of aluminium (Al) with 85.0 g of chlorine (Cl2). Using the information in the equation, explain how you would determine which reactant is in excess and calculate the maximum mass of aluminium chloride (AlCl3) that could be formed.
(Ar: Al = 27, Cl = 35.5)
Question 395
4 marks · Normal
Answer and see the solution →A compound contains 9.45 g potassium, 5.25 g phosphorus, and 12.80 g oxygen.
(Ar: K = 39, P = 31, O = 16)
(a)[2 marks]Calculate the number of moles of each element present in the sample.
(b)[2 marks]Determine the empirical formula of the compound.
Question 396
1 mark · Normal
Answer and check →Which of the following could be a method for determining the empirical formula of a metal oxide?
- A.Burning the metal in air and weighing the increase in mass
- B.Measuring the temperature before and after mixing with water
- C.Electrolysing the metal and collecting the gas
- D.Testing the metal with universal indicator
Question 397
2 marks · Normal
Answer and see the solution →Write the balanced chemical equation, with state symbols, for the reaction of calcium carbonate with dilute nitric acid to form calcium nitrate, carbon dioxide, and water.
Question 398
4 marks · Normal
Answer and see the solution →Answer the questions about calcium hydroxide, Ca(OH)2.
(a)[1 mark]State the relative atomic masses (Ar) for Ca, O, and H.
(b)[2 marks]Calculate the relative formula mass (Mr) of Ca(OH)2.
(c)[1 mark]What mass of Ca(OH)2 is present in 0.5 mol of the compound?
Question 399
2 marks · Hard
Answer and see the solution →The molecular formula of a hydrocarbon is found to be C6H12. State its empirical formula.
Question 400
5 marks · Hard
Answer and see the solution →An experiment is carried out to determine the formula of a hydrated salt, magnesium sulfate crystals, MgSO4·nH2O. The following results are obtained:
Measurement Mass / g Mass of empty crucible 28.60 Mass of crucible + hydrated salt before heating 30.88 Mass of crucible + salt after heating to constant mass (anhydrous MgSO4) 30.00 (Ar: Mg = 24, S = 32, O = 16, H = 1)
(a)[1 mark]Calculate the mass of water lost during heating.
(b)[2 marks]Calculate the number of moles of anhydrous magnesium sulfate (MgSO4) present after heating. (Show your working.)
(c)[2 marks]Determine the value of n in the formula MgSO4·nH2O. (Show your working.)