Which of the following particles are subatomic particles? 1. Electron 2. Proton 3. Neutron 4. Muon Select the correct answer using the code given below.
- A.1 and 4 only
- B.1, 2, 3 and 4
- C.2 and 3 only
- D.1, 2 and 3 only
Correct answer
Explanation
The correct answer is B, 1, 2, 3 and 4. Any particle smaller than an atom is a subatomic particle, and the muon qualifies just as the electron, proton and neutron do.
Electrons, protons and neutrons are the subatomic particles that build atoms: protons and neutrons sit in the nucleus and electrons move around it. Protons and neutrons are themselves made of quarks. The muon is an elementary particle of the lepton family, like the electron but about 207 times heavier, carrying the same negative charge. It is unstable and decays in about 2.2 microseconds. Muons are produced in large numbers when cosmic rays strike the upper atmosphere, and many reach the ground. Being far smaller than an atom, the muon is a subatomic particle.
A is wrong: it leaves out the proton and neutron.
C is wrong: it leaves out the electron and the muon.
D is wrong: it misses the muon, which is also subatomic even though it is not part of ordinary atoms.
Exam tip: subatomic means smaller than an atom; leptons (electron, muon, neutrino) and quarks are elementary, protons and neutrons are made of quarks.
Practice Questions
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- B.diploid zygote
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- B.Two
- C.Three
- D.Four
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- A.10⁻⁷ cm
- B.10⁻⁶ cm
- C.10⁻⁴ cm
- D.10⁻³ cm
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Read the full explanation →Which of the following is the general formula for saturated hydrocarbons?
- A.CₙH₂ₙ₊₂
- B.CₙH₂ₙ₋₂
- C.CₙH₂ₙ₊₁
- D.CₙH₂ₙ₋₁
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- A.Cholera
- B.Malaria
- C.Smallpox
- D.Elephantiasis
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