1 Which human activity is a major source of carbon dioxide emissions? A Planting trees B Burning fossil fuels C Using solar energy D Recycling waste
2 In a displacement reaction, which halogen can displace bromine from a solution of potassium bromide? A Iodine B Chlorine C Bromine D Fluorine
3 Which of the following is a characteristic physical property of metals? A They are brittle B They are good conductors of electricity C They have low melting points D They are poor conductors of heat
4 Which of the following elements is a noble gas with a stable electronic structure and is used in neon signs? A Sodium B Chlorine C Neon D Iron
5 Which of the following is an effect of global warming? A Rising sea levels B Decrease in Earth's temperature C More oxygen in atmosphere D Less carbon dioxide
7 Which of the following is a use of transition elements? A As catalysts in industrial reactions B As inert gases in balloons C As disinfectants in water D As fuels in cars
9 Which of the following is a characteristic physical property of Group 1 elements (alkali metals)? A They are poor conductors of electricity. B They are soft and can be cut with a knife. C They have high melting points. D They are dense and heavy metals.
10 Which air pollutant is mainly produced by incomplete combustion of fossil fuels? A Carbon dioxide B Carbon monoxide C Sulphur dioxide D Ozone
11 Why are noble gases unreactive? A They have a full outer shell of electrons B They are metals C They have one electron in their outer shell D They are radioactive
13 Which of the following is a strategy to reduce environmental issues caused by air pollution? A Increasing the use of fossil fuels B Cutting down forests C Using catalytic converters in vehicles D Burning more waste in open air
14 What is the role of a catalytic converter in vehicles? A To increase fuel consumption B To reduce harmful emissions C To produce more carbon dioxide D To cool the engine
15 Acid rain is formed when sulphur dioxide and nitrogen oxides react with: A Water vapour B Oxygen C Nitrogen D Carbon dioxide
16 Which gas is the most abundant in the Earth's atmosphere? A Oxygen B Nitrogen C Carbon dioxide D Argon
17 In a displacement reaction, chlorine is added to potassium bromide solution. What will happen? A No reaction B Bromine will displace chlorine C Chlorine will displace bromine D Potassium will displace chlorine
19 Which property allows metals to be drawn into wires? A Malleability B Ductility C Brittleness D Conductivity
20 Which gas is a colorless, odorless, and highly toxic air pollutant? A Carbon dioxide B Carbon monoxide C Sulphur dioxide D Nitrogen
21 Which of the following is a use of helium? A In balloons B In water treatment C In catalysts D In fertilizers
22 Which of the following is a particulate air pollutant? A Carbon dioxide B Sulphur dioxide C Dust D Nitrogen
23 Which property is shown by metalloids? A They are always gases B They have properties of both metals and non-metals C They are always shiny and malleable D They do not conduct electricity at all
25 What is the colour of bromine at room temperature? A Pale yellow-green B Red-brown C Purple-black D Colourless