Combined Science Revision Question 1 Outline how industrial gases are manufactured from air. Solution 1 Air is cooled to -78°C. 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 -200°C. At this temperature all gases are …
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 described? Substance Bonding A Argon …
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 acid? d) Which substance could …
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 cold water but it reacts …
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 you test for each product …
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 Does not conduct electricity Conducts …
Combined Science Practice Questions. Combined Science practice questions for Zimsec O’level Students. I have divided them into sections in which they belong. I will upadate the answers and explanations later on. Biology Section questions Why is photosynthesis an important process to all living organisms? Write a word equation to summarise the process of photosynthesis. By …