Questions (120)
Q1CDS2020
Scattering of α-particles by a thin gold foil suggests the presence of
- A electron in an atom
- B proton in an atom
- C positively charged nucleus at the centre of an atom ✓
- D isotopes of gold
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
Q2CDS2020
The elements of which of the following pairs are isobars?
- A ₁¹H and ₁²H
- B ₁¹H and ₁³H
- C ₆¹²C and ₆¹⁴C
- D ₁₈⁴⁰Ar and ₂₀⁴⁰Ca ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
Q3CDS2020
Which one of the following chemical reactions is not feasible?
- A Fe + CuSO₄ → FeSO₄ + Cu
- B Zn + CuSO₄ → ZnSO₄ + Cu
- C Cu + PbCl₂ → CuCl₂ + Pb ✓
- D Mg + CuSO₄ → MgSO₄ + Cu
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry
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