Download App

Model Paper 5 — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceModel Paper 51 Mark
MCQ
An atom with 3 protons and 4 neutrons will have valency of
  • A
    4
  • ✓
    1
  • C
    7
  • D
    3
✓

Answer

Correct option: B.
1
(b) 1
Explanation: Atomic number = Number of protons = 3
Mass number = Number of protons + number of neutrons =3 + 4 = 7
Electronic configuration of the atom is 2,1(K,L)
Hence, its valency is 1.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q. [1 M]" from Model Paper 5→Model Paper 5 — all question types→Science STD 9 question papers→Gujarat Board STD 9 question papers→Gujarat Board question paper generator→

Similar questions

At $20^\circ C,$ the minimum distance of a person from a sound reflecting surface to hear an echo is:
→
Poultry fowl are susceptible to the following pathogens.
→
Which of the following is not colloid:
→
The principal cereal crop of India is:
→
The normal body cell of an organism contains $28$ pairs of chromosomes. The number of chromosomes present in its germ cell will be?
→
The law of constant phosphorus, sulphur and krypton, the elements having the lowest and highest atomicities are respectively:
→
Which of the following does not possess the ability to do work not because motion?
→
Milk does not provide:
→
Biosphere occurs:
→
The weight of an object at the centre of the earth of radius R is:
→