One mole of CO₂ contains?

A. 6.022 × 10²³ atoms of carbon

B. 6.022 × 10²³ atoms of oxygen

C. 6.022 × 10²³ molecules of carbon

D. 6.022 × 10²³ atoms of CO₂

Everyday Science · Atoms, Elements & Compounds · page 6 of 30

Atoms MCQs with Answers

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Atoms MCQs (51–60)

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51.
Where are protons and neutrons located in an atom?
Correct Answer: B. In the nucleus
One-liner
Protons and neutrons are located in the nucleus of an atom.
52.
Which of the following transition metals in its ground state has an unpaired electron in an s-orbital?
Correct Answer: B. Cr
One-liner
Cr (Chromium) in its ground state has an unpaired electron in an s-orbital due to its exceptional [Ar] 3d⁵ 4s¹ electronic configuration.
53.
The mass of one mole of electron is?
Correct Answer: A. 0.55 mg
One-liner
The mass of one mole of electrons is 0.55 mg.
54.
Which formula helps in the determination of the maximum number of electrons present in an orbit?
Correct Answer: A. 2n^2
One-liner
The maximum number of electrons that can be accommodated in an orbit (shell) is given by the formula 2n², where n is the principal quantum number (shell number).
55.
Which of the following is the electronic configuration of an alkali earth metal of 3rd period?
Correct Answer: C. [Ne] 3s²
One-liner
The electronic configuration of the alkali earth metal of the 3rd period is [Ne] 3s², which corresponds to magnesium (Mg).
56.
Which one is the heaviest particle?
Correct Answer: C. Neutron
One-liner
The Neutron is the heaviest particle among the given options, being slightly heavier than the proton.
57.
The maximum number of electrons L orbit possesses?
Correct Answer: B. 8
One-liner
The L orbit (second energy shell, n=2) can hold a maximum of 8 electrons.
58.
Electronic configuration is distribution of _?
Correct Answer: D. Electrons
One-liner
Electronic configuration is the distribution of electrons in different shells (energy levels) around the nucleus of an atom.
59.
One mole of CO₂ contains?
Correct Answer: A. 6.022 × 10²³ atoms of carbon
One-liner
One mole of CO₂ contains 6.022 × 10²³ atoms of carbon (Avogadro's number of carbon atoms).
60.
Number of electrons lost by atoms of group IIIA equals ?
Correct Answer: C. 3
One-liner
Atoms of group IIIA lose 3 electrons to achieve a stable noble gas configuration.

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Atoms MCQs (51–60)

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