Element 3: Lithium (Li) / āĻŽā§āϞ ā§Š: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ (Li) â Used in rechargeable batteries, medicines.
- Name: Lithium / āύāĻžāĻŽ: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ
- Symbol: Li / āĻāĻŋāĻšā§āύ: Li
- Atomic Number: 3 / āĻĒāĻžā§°āĻŽāĻžāĻŖā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻž: ā§Š
- Nature: Metal / āĻĒā§ā§°āĻā§āϤāĻŋ: āϧāĻžāϤā§
Lithium is the lightest metal. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻšā§āĻā§ āĻāĻāĻžāĻāϤāĻā§ āĻĒā§āĻšā§° āϧāĻžāϤā§āĨ¤
Structure of Atom / āĻĒā§°āĻŽāĻžāĻŖā§ā§° āĻāĻ āύ
- Protons: 3 / āĻĒā§ā§°ā§āĻāύ: ā§Š
- Electrons: 3 / āĻāϞā§āĻā§āĻā§ā§°āύ: ā§Š
- Neutrons: 4 (usually) / āύāĻŋāĻāĻā§ā§°āύ: ā§Ē (āϏāĻžāϧāĻžā§°āĻŖāϤā§)
Simple atomic structure. : āϏāĻšāĻ āĻĒā§°āĻŽāĻžāĻŖā§ āĻāĻ āύāĨ¤
Properties / āĻā§āĻŖāϏāĻŽā§āĻš
- Very light metal / āĻŦāĻšā§āϤ āĻĒā§āĻšā§° āϧāĻžāϤā§
- Soft (can be cut) / āĻā§āĻŽāϞ (āĻāĻžāĻāĻŋāĻŦ āĻĒāĻžā§°āĻŋ)
- Reacts with air & water / āĻŦāĻžāϝāĻŧā§ āĻā§°ā§ āĻĒāĻžāύā§ā§° āϏā§āϤ⧠āĻŦāĻŋāĻā§ā§°āĻŋāϝāĻŧāĻž āĻā§°ā§
- Stored in oil / āϤā§āϞāϤ āϏāĻā§°āĻā§āώāĻŖ āĻā§°āĻž āĻšāϝāĻŧ
Uses / āĻŦā§āĻ¯ā§ąāĻšāĻžā§°
- Batteries / āĻŦā§āĻāĻžā§°ā§ (āĻŽ’āĻŦāĻžāĻāϞ, āϞā§āĻĒāĻāĻĒ)
- Mobile phones / āĻŽā§āĻŦāĻžāĻāϞ āĻĢā§āύāϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧ
- Electric cars / āĻŦā§āĻĻā§āϝā§āϤāĻŋāĻ āĻāĻžāĻĄāĻŧā§āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧ
Importance / āĻā§ā§°ā§āϤā§āĻŦ
- Main part of rechargeable batteries
- Important for modern devices
- Key material for electric vehicles
Why Stored in Oil ? / āĻāĻŋāϝāĻŧ āϤā§āϞāϤ ā§°āĻāĻž āĻšāϝāĻŧ ?
Lithium reacts quickly with air and water. :āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻŦāĻžāϝāĻŧā§ āĻā§°ā§ āĻĒāĻžāύā§ā§° āϏā§āϤ⧠āϤā§āĻā§āώāĻŖāĻžāϤ āĻŦāĻŋāĻā§ā§°āĻŋāϝāĻŧāĻž āĻā§°ā§āĨ¤
So it is kept in oil to protect it. : āϏā§āϝāĻŧā§ āĻāϝāĻŧāĻžāĻ āϤā§āϞāϤ ā§°āĻžāĻāĻž āĻšāϝāĻŧāĨ¤
Fact / āϤāĻĨā§āϝ : Lithium is used in rechargeable batteries. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻĒā§āύ⧰ āĻāĻžā§°ā§āĻ āĻā§°āĻŋāĻŦ āĻĒā§°āĻž āĻŦā§āĻāĻžā§°ā§āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧāĨ¤
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Lithium (Li) – PYQ MCQs
Q1. Lithium belongs to which group of the periodic table ? : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻā§ąā§°ā§āϤ āϏāĻžā§°āĻŖā§ā§° āĻā§āύāĻā§ āĻā§āĻāϤ āĻĒā§°ā§ ?
(a) Group 1 (b) Group 2 (c) Group 17 (d) Group 18
Ans: (a) Group 1
Explanation: Lithium is an alkali metal, placed in Group 1. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻāĻāĻž āĻā§āώāĻžā§° āϧāĻžāϤā§, āϏā§āϝāĻŧā§ āĻā§āĻ ā§§āϤ āĻĨāĻžāĻā§āĨ¤
Q2. Atomic number of lithium is: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽā§° āĻĒāĻžā§°āĻŽāĻžāĻŖā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻž āĻāĻŋ ?
(a) 2 (b) 3 (c) 4 (d) 5
Ans: (b) 3
Explanation: Atomic number = number of protons = 3. : āĻĒāĻžā§°āĻŽāĻžāĻŖā§ąāĻŋāĻ āϏāĻāĻā§āϝāĻž = āĻĒā§ā§°ā§āĻāύ⧰ āϏāĻāĻā§āϝāĻž = ā§ŠāĨ¤
Q3. Lithium is classified as: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽāĻ āĻā§āύā§āĻā§ āĻļā§ā§°ā§āĻŖā§āĻŦāĻĻā§āϧ āĻā§°āĻž āĻšāϝāĻŧ ?
(a) Non-metal (b) Metalloid (c) Metal (d) Noble gas
Ans: (c) Metal
Explanation: Lithium is a metal. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻāĻāĻž āϧāĻžāϤā§āĨ¤
Q4. Number of electrons in lithium atom is: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻĒā§°āĻŽāĻžāĻŖā§āϤ āĻāĻŋāĻŽāĻžāύ āĻāϞā§āĻā§āĻā§ā§°āύ āĻĨāĻžāĻā§ ?
(a) 2 (b) 3 (c) 4 (d) 5
Ans: (b) 3
Explanation: Lithium has 3 electrons equal to its atomic number. : āĻāϝāĻŧāĻžāϤ ā§ŠāĻāĻž āĻāϞā§āĻā§āĻā§ā§°āύ āĻĨāĻžāĻā§āĨ¤
Q5. Lithium is stored in oil because: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āϤā§āϞāϤ ā§°āĻžāĻāĻž āĻšāϝāĻŧ āĻāĻžā§°āĻŖ -
(a) It is heavy (b) It reacts with air (c) It is solid (d) It is hard
Ans: (b) It reacts with air
Explanation: Lithium reacts with air and water, so it is stored in oil. : āĻ āĻŦāĻžāϝāĻŧā§ āĻā§°ā§ āĻĒāĻžāύā§ā§° āϏā§āϤ⧠āĻŦāĻŋāĻā§ā§°āĻŋāϝāĻŧāĻž āĻā§°ā§, āϏā§āϝāĻŧā§ āϤā§āϞāϤ ā§°āĻžāĻāĻž āĻšāϝāĻŧāĨ¤
Q6. Lithium is mainly used in: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻŽā§āĻā§āϝāϤ āĻ’āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧ ?
(a) Clothes (b) Batteries (c) Wood (d) Cement
Ans: (b) Batteries
Explanation: Lithium is widely used in batteries. : āĻŦā§āĻāĻžā§°ā§āϤ āĻŦā§āϝāĻžāĻĒāĻ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧāĨ¤
Q7. Lithium is: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻšā§āĻā§ -
(a) Hard metal (b) Soft metal (c) Gas (d) Liquid
Ans: (b) Soft metal
Explanation: Lithium is a soft metal that can be cut. : āĻ āĻā§āĻŽāϞ āϧāĻžāϤā§āĨ¤
Q8. How many protons are present in lithium ? : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽāϤ āĻāĻŋāĻŽāĻžāύ āĻĒā§ā§°ā§āĻāύ āĻĨāĻžāĻā§ ?
(a) 2 (b) 3 (c) 4 (d) 5
Ans: (b) 3
Explanation: Protons = atomic number = 3. : āĻĒā§ā§°ā§āĻāύ = ā§ŠāĨ¤
Q9. Lithium is the ______ metal. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻšā§āĻā§ ______ āϧāĻžāϤā§āĨ¤
(a) Heaviest (b) Lightest (c) Strongest (d) Hardest
Ans: (b) Lightest
Explanation: Lithium is the lightest metal. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻāĻāĻžāĻāϤāĻā§ āĻĒā§āĻšā§° āϧāĻžāϤā§āĨ¤
Q10. Lithium is used in electric cars because: āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻŦā§āĻĻā§āϝā§āϤāĻŋāĻ āĻāĻžāĻĄāĻŧā§āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻā§°āĻž āĻšāϝāĻŧ āĻāĻžā§°āĻŖ -
(a) It is heavy (b) It stores energy (c) It is weak (d) It is gas
Ans: (b) It stores energy
Explanation: Lithium batteries store electrical energy efficiently. : āϞāĻŋāĻĨāĻŋāϝāĻŧāĻžāĻŽ āĻŦā§āĻāĻžā§°ā§āϝāĻŧā§ āĻļāĻā§āϤāĻŋ āϏāĻā§āĻāϝāĻŧ āĻā§°ā§āĨ¤