Charu Maini, Meenambika Menon and, Vandana Saxena Solutions for Chapter: Changes Around Us, Exercise 3: EXERCISES
Charu Maini Science Solutions for Exercise - Charu Maini, Meenambika Menon and, Vandana Saxena Solutions for Chapter: Changes Around Us, Exercise 3: EXERCISES
Attempt the free practice questions on Chapter 6: Changes Around Us, Exercise 3: EXERCISES with hints and solutions to strengthen your understanding. Head Start Science 6 solutions are prepared by Experienced Embibe Experts.
Questions from Charu Maini, Meenambika Menon and, Vandana Saxena Solutions for Chapter: Changes Around Us, Exercise 3: EXERCISES with Hints & Solutions
What are reversible and irreversible changes? Give examples.
Justify the statement - physical changes can be reversible as well as irreversible.
Justify the statement giving examples — heating brings about chemical changes in some substances whereas physical changes in others.
Addition of water to salt or sand is a physical change whereas to cement is a chemical change. Justify the statement.
Why does a glass tumbler containing hot water crack if we cool it by pouring cold water on it?
Have you ever lighted a candle on festivals, birthdays or some other occasions? You must have observed the following when a candle is lighted:
• Candle burns to produce carbon dioxide, water vapour and light.
• The size of the candle decreases.
• Some of the wax melts.
Now classify the above changes as reversible or irreversible.
Instead of mercury metal can we use copper metal in a thermometer? (Hint: which state, solid or liquid, shows more expansion or contraction on change of temperature)
Sam took out porridge kept in a glass bowl from the refrigerator. As he wanted to have it hot, he put it directly into the microwave oven for heating. To his surprise the glass bowl had cracked!! Can you help him figure out why this had happened?
