Chemical Reactions Quiz

What is a common observation when milk is left at room temperature during summers?

• It turns into yogurt

• It freezes

• It evaporates

• It remains unchanged

What happens to an iron tawa/pan/nail when exposed to a humid atmosphere?

• It rusts

• It shines

• It breaks

• It becomes heavier

What is the result of food being cooked?

• It becomes inedible

• It remains raw

• It becomes digestible

• It cools down

What is the primary change observed when food is digested in our body?

• It is expelled as waste

• It is converted into energy

• It increases in volume

• It remains unchanged

What do you observe when burning a magnesium ribbon as described in the activity?

• The magnesium ribbon disappears

• The magnesium ribbon melts

• The magnesium ribbon collects as a white ash

• The magnesium ribbon changes color but remains intact

What is formed when magnesium ribbon is burnt in the presence of oxygen?

• Magnesium hydroxide

• Magnesium oxide

• Magnesium chloride

• Magnesium sulphate

What are the signs that a chemical reaction has taken place according to the text?

• Change in state and evolution of a gas

• Change in temperature and color

• Evolution of a gas and change in temperature

• All of the above

What does the arrow in a chemical equation represent?

• The direction of the reaction

• The reactants of the reaction

• The products of the reaction

• The speed of the reaction

What happens when zinc granules are added to dilute sulphuric acid?

• Formation of zinc oxide

• Decrease in temperature

• Formation of hydrogen gas

• No reaction occurs

What is the primary purpose of writing a chemical equation according to the text?

• To predict the products of a chemical reaction

• To provide a concise and useful representation of a chemical reaction

• To list the physical states of reactants and products

• To calculate the energy changes in the reaction