Science Quiz

Why do radiant heaters effectively warm a room without heating the air directly?

• They transfer heat by conduction

• They emit infrared radiation

• They cause convection currents

• They use chemical reactions

Solar panels rely on which process to convert sunlight into energy?

• Conduction of heat

• Absorption of radiant energy

• Convection of air

• Reflection of visible light

Why do dark-colored surfaces absorb more solar radiation than light-colored surfaces?

• They reflect more light

• They have higher emissivity

• They absorb more infrared radiation

• They conduct heat better

Which observation confirms that a chemical change has occurred?

• A substance changes shape

• A gas is produced during a reaction

• A liquid evaporates

• A solid dissolves in water

What is the word equation for the reaction between sulfuric acid and magnesium?

• Sulfuric acid + Magnesium → Magnesium sulfate + Hydrogen

• Sulfuric acid + Magnesium → Magnesium oxide + Water

• Sulfuric acid + Magnesium → Magnesium chloride + Hydrogen

• Sulfuric acid + Magnesium → Magnesium sulfate + Oxygen

In the reaction between sodium carbonate and hydrochloric acid, the products are:

• Sodium chloride, water, and oxygen

• Sodium chloride, water, and carbon dioxide

• Sodium carbonate and hydrogen

• Sodium hydroxide and carbon dioxide

During a chemical reaction, the total number of atoms:

• Increases as new substances form

• Decreases due to energy loss

• Remains constant

• Depends on the reaction type

If 12 g of reactants produce 12 g of products in a closed system, what is true about chemical reactions?

• Heat is produced

• Gas is produced

• Mass of reactants and products are different

• Mass of reactants and products are the same

Which type of chemical change occurs when calcium carbonate is heated to form calcium oxide and carbon dioxide?

• Combustion

• Thermal decomposition

• Oxidation

• Neutralisation

Rusting requires the presence of:

• Oxygen and nitrogen

• Nitrogen and water

• Carbon dioxide and water

• Oxygen and water