How much time would it take to distribute one Avogadro number of wheat grains, if 1010 grains are distributed each second?
We know , Avogadro number = 6.023 × 1023
Therefore , time taken for distributing the grains
= (6.023 × 1023 x 1) / 1010 = 6.023 x 1013 s
By Converting these seconds into years, we get
= (6.023 x 1013) / (60 x60x24x365)
= 1,90,9800 y
Hence, the time taken would be 1.909 x 106 years.
What will be the minimum pressure required to compress 500 dm3 of air at 1 bar to 200 dm3 at 30°C?
At 0°C, the density of a certain oxide of a gas at 2 bar is same as that of dinitrogen at 5 bar. What is the molecular mass of the oxide?
Density of a gas is found to be 5.46 g/dm3 at 27 °C at 2 bar pressure. What will be its density at STP?
Calculate the temperature of 4.0 mol of a gas occupying 5 dm3 at 3.32 bar.
(R = 0.083 bar dm3 K–1 mol–1).
A vessel of 120 mL capacity contains a certain amount of gas at 35 °C and 1.2 bar pressure. The gas is transferred to another vessel of volume 180 mL at 35 °C. What would be its pressure?
Calculate the total pressure in a mixture of 8 g of dioxygen and 4 g of dihydrogen confined in a vessel of 1 dm3 at 27°C. R = 0.083 bar dm3 K–1 mol–1.
Calculate the volume occupied by 8.8 g of CO2 at 31.1°C and 1 bar pressure.
R = 0.083 bar L K–1 mol–1.
34.05 mL of phosphorus vapour weighs 0.0625 g at 546 °C and 0.1 bar pressure. What is the molar mass of phosphorus?
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What would be the SI unit for the quantity pV2T 2/n?
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(i) CH2=C=O,
(ii) CH3CH=CH2,
(iii) (CH3)2CO,
(iv) CH2=CHCN,
(v) C6H6
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(ii) CO2
(iii) CH4
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(a) NaH2PO4
(b) NaHSO4
(c) H4P2O7
(d) K2MnO4
(e) CaO2
(f) NaBH4
(g) H2S2O7
(h) KAl(SO4)2.12 H2O
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(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure?
Justify the position of hydrogen in the periodic table on the basis of its electronic configuration.
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CCl4(g) → C(g) + 4 Cl(g)
and calculate bond enthalpy of C – Cl in CCl4(g).
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ΔfH0 (CCl4) = –135.5 kJ mol–1.
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The diameter of zinc atom is 2.6 Å .
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(a) radius of zinc atom in pm and
(b) number of atoms present in a length of 1.6 cm if the zinc atoms are arranged side by side lengthwise.
Boric acid is polymeric due to
(a) its acidic nature (b) the presence of hydrogen bonds (c) its monobasic nature (d) its geometry
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(b) CH3CH2COOH > (CH3)2CHCOOH > (CH3)3C.COOH
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Why the Avogadro's no. Divide by 10^10
This ans is correct . But it can be more explained clearly
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How to convert seconds into years
Respected sir If a man counts four grain of wheat each second than how much time he takes to count one mol of wheat grain?