Question

From A, B, C, D, which weighs the least —
A : 2 g. atoms of Nitrogen
B : 1 mole of Silver
C : 22.4 lits. of oxygen gas at 1 atmos. press. and 273 K
D : 6.02 x 1023 atoms of carbon.
[Ag = 108, N = 14, O = 16, C = 12]

August 4, 2024

Answer

D : 6.02 × 10²³ atoms of carbon.

Reason

Gram molecular mass of carbon is least.

💡 Some Related Questions

Copper [II] sulphate soln. reacts with sodium hydroxide soln. to form copper hydroxide according to the equation :
2NaOH + CuSO4 ⟶ Na2SO4 + Cu(OH)2↓
What mass of copper hydroxide is precipitated by using 200 g of sodium hydroxide.
[H = 1, O = 16, Na = 23, S = 32, Cu = 64]

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Al4C3 + 12H2O ⟶ 4Al(OH)3 + 3CH4
(i) State what mass of aluminium hydroxide is formed from 12 g. of aluminium carbide.
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[relative molecular weight of Al4Cl3] = 144 ; Al(OH)3 = 78

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From the equation :
(NH₄)₂Cr₂O₇ ⟶ N₂(g) + 4H₂O(g) + Cr₂O₃
Calculate:
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(NH₄)₂Cr₂O₇ is heated.
(ii) the quantity in moles of N₂ formed.
(iii) the volume in litres or dm3 of N₂ evolved at s.t.p.
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