📘 Class 10 – Science

Q. What is a chemical reaction?

Ans: A process where new substances are formed.

Q. What is a chemical equation?

Ans: Representation of chemical reaction using symbols.

Q. What is a balanced equation?

Ans: Atoms are equal on both sides.

Q. What is oxidation?

Ans: Gain of oxygen or loss of hydrogen.

Q. What is reduction?

Ans: Loss of oxygen or gain of hydrogen.

Q. What is corrosion?

Ans: Slow destruction of metals.

Q. Example of corrosion?

Ans: Rusting of iron.

Q. What is rancidity?

Ans: Spoilage of food due to oxidation.

Q. Why are reactions important?

Ans: They are part of daily life.

Q. What is a reactant?

Ans: Substance taking part in reaction.

Q. What is oxidation?

Ans: Loss of electrons.

Q. What is reduction?

Ans: Gain of electrons.

Q. Chemical formula of washing soda?

Ans: Na₂CO₃·10H₂O

Q. pH of acidic solution?

Ans: Less than 7

Q. Unit of electric current?

Ans: Ampere

Q. Ohm’s Law?

Ans: V = IR

Q. Power formula?

Ans: P = VI

Q. Human chromosome pairs?

Ans: 23 pairs

Q. Functional unit of kidney?

Ans: Nephron

Q. Greenhouse gas example?

Ans: Carbon dioxide