Easy-to-understand Combined Science homework and revision materials for your GCSE O level Combined Science exams preparation.
Acids, Bases and Salts Question 2 The table below shows the effect of three substances A, B and C on universal indicator solution. substance effect on universal indicator solution A red B green C purple i. State the function of the universal indicator solution. [1] ii. Deduce the nature of Read more…
Acids, Bases and Salts Question 1 Calcium sulphate can be formed by the reaction between calcium carbonate and solution X. Two other substances are produced in this reaction. Name solution X. [1] Name the other two products. [2] Name the type of reaction that occur between calcium carbonate and X. Read more…
Atomic Structure and Bonding Question 1 The mass number of potassium is 39 and its proton number is 19. i. State the number of electrons in the potassium atom. [1] ii. Determine the number of neutrons in the potassium atom. [1] Potassium reacts with chlorine by donating electrons. i. State Read more…
Atomic Structure and Bonding Question 2 Chlorine has two types of atoms as shown, 35Cl and 37Cl.i. State the name given to the two types of chlorine atoms shown. [1]ii. Calculate the number of neutrons in 35Cl. [1] Chlorine reacts with sodium to form sodium chloride (NaCl).i. Name the type Read more…
Combined Science Revision Solution 1 Air is cooled to -78ยฐC. Water and carbon dioxide are removed as solids. The remaining air is further cooled by a process of rapid compression and expansion until it reaches a temperature of -200ยฐC. At this temperature all gases are liquids except for rare gases. Read more…
Combined Science Chemistry Section Multiple Choice (Page 1) The diagram shows the electronic structure of an atom of a certain element, Z. Z will most likely form: A. Z+ ions B. Z2+ ions C. Z– ions D. Z2- ions For which one of the following substances is the bonding correctly Read more…
Mixed Revision Questions and Answers (Page 1) Question 1 Use the table below to answer the questions that follow: Substance pH A 1 B 5 C 7 D 9 E 14 a) Which substance is a weak alkali? b) Which substance could be water? c) Which substance is a weak Read more…
Metals Questions and Answers (Page 1) Question 1 Potassium is a metal above magnesium in the reactivity series. How would you expect it to react with (a) oxygen (b) water? Solution 1 (a) Reacts vigorously with oxygen (b) Reacts vigorously with water Question 2 A metal does not react with Read more…
Organic Chemistry Questions and Answers (Page 1) Question 1 The hydrocarbon methane is the first member of the alkanes homologous series. a) Draw diagrams to show the first 3 members of the alkanes homologous series. b) What substances will be formed when methane burns in plentiful air supply? How would Read more…
Acids, Bases and Salts Questions and Answers (Page 1) Question 1 Dry hydrogen chloride gas does not turn blue litmus paper red. It dissolves in water and toluene. Some properties of the two solutions are listed below: HCl in toluene HCl in water Nuetral to litmus Turns litmus paper red Read more…