Fill in the blanks in the following statements:
a) When carbon dioxide is passed through lime water, it turns milky due to the formation of ___________.
b) The chemical name of baking soda is__________.
c) Two methods by which rusting of iron can be prevented are___________ and _______
d) Change in which only ───── properties of a substance change are called physical changes.
e) Changes in which new substances are formed are called ────── changes.
(a) When carbon dioxide is passed through lime water, it turns milky due to the formation of Calcium carbonate.
When carbon dioxide is passed through lime water, calcium carbonate is formed, which makes lime water milky. It is a chemical process.
(b) The chemical name of baking soda is sodium hydrogen carbonate.
It is popularly called cooking soda. The chemical formula of baking soda is NaHCO3).
(c) Two methods by which rusting of iron can be prevented are painting and galvanization.
Painting and galvanization are two methods to prevent iron articles from coming in contact with oxygen, or water, or both. Thus, prevent rusting of iron.
(d) Change in which only physical properties of a substance change are called physical changes.
A physical change is the one in which a substance undergoes a change in its physical properties. In such a change, no new substance is formed.
(e) Changes in which new substances are formed are called chemical change.
Chemical change is a change where a substance is changed and a new substance is formed.