Class 5 EVS Chapter 7 Question Answers - Chapter 7 - Experiments with Water

Q1. What makes an object float on water?
Ans: An object will float on water if its weight is less than the water displaced by it.

Q2. Why did the puri float in the hot oil?
Ans: The puri floated in the hot oil because its weight was less than the oil displaced by it.

Q3. What happened to the eggs when Ayesha put too much salt in the water?
Ans: The eggs floated a little when Ayesha put too much salt in the water because the water became denser and the weight of the liquid displaced by the eggs was more than the eggs themselves.

Q4. What are soluble substances?
Ans: Soluble substances are substances that disappear in water when we add them to it. Examples include salt, sugar, glucose, vinegar, and lemon juice.

Q5. What are insoluble substances?
Ans: Insoluble substances are substances that do not disappear in water but settle down when we add them to it. Examples include salt, sand, pebbles, chalk powder, and cement.

Q6. How can we dissolve things quickly in water?
Ans: We can dissolve things quickly in water by continuously stirring the solution while adding soluble substances to it or by heating the mixture.

Q7. Why doesn't oil mix with water?
Ans: Oil doesn't mix with water because it is an immiscible liquid and forms a layer on the surface of the water.

Q8. What happens when we put drops of water, oil, and sugar solutions on the lid of a tiffin box and tilt it?
Ans: The drops of water will slide faster than the drops of oil and sugar solutions because the drops of oil and sugar solutions are stuck on the lid of the tiffin box, making it difficult to slide.

Q9. What are soluble substances examples?
Ans: Salt, sugar, glucose, vinegar, and lemon juice are examples of soluble substances.

Q10. What are insoluble substances examples?
Ans: Salt, sand, pebbles, chalk powder, and cement are examples of insoluble substances.