Advertisements
Advertisements
प्रश्न
Empirical formula of a compound is CH2O. If its empirical formula is equal to its vapour density, calculate the molecular formula of the compound.
Advertisements
उत्तर
Empirical formula of the compound is CH2O.
Empirical formula mass = Atomic mass of C + Atomic mass of H + Atomic mass of O
= 12 + 2 x 1 + 16 = 30.
Now as empirical formula is equal to the vapour density then;
Molecular mass = 2 x vapour density
= 2 x 30 = 60
n = Molecular mass/Empirical formula mass
= 60 / 30 = 2
Molecular formula = n x empirical formula
= 2 x (CH2O) = C2H4O2
The molecular formula of the compound is C2H4O2
APPEARS IN
संबंधित प्रश्न
Calculate the relative molecular mass of Chloroform.
(use K = 39, Cl = 35.5, O = 16, C = 12, H = 1, Na = 23, N = 14, S= 32)
An organic compound has the following percentage composition: C = 12.76%, H = 2.13%, Br = 85.11%. The vapour density of the compound is 94. Find out its molecular formula.
Calculate the percentage of boron (B) in borax (Na2B4O7.10H2O). [H = 1, B = 11, O = 16, Na = 23],
answer correct to 1 decimal place.
When excess lead nitrate solution was added to a solution of sodium sulphate, 15.1g of lead sulphate was precipitated. What mass of sodium sulphate was present in the original solution?
Na2SO4 + Pb(NO3)2 → PbSO4 + 2NaNO3
(H = 1, C = 12, O = 16, Na = 23, S = 32, Pb = 207)
Calculate the percentage of phosphorous in the fertilizer superphosphate, Ca(H2PO4)2. [Ca = 40, H =1, P =31, O = 16] (Correct to 1 decimal place)
The reaction of potassium permanganate (VII) with acidified iron (II) sulphate is given below:
2KMno4 + 10FeSO4 + 8H2O → K2SO4 + 2MnSO4 + 5Fe2(SO4)3 + 8H2O
If 15.8g of potassium permanganate (VII) was used in the reaction, calculate the mass of iron (II) sulphate used in the above reaction.
A gaseous hydrocarbon contains 82.76% of carbon. Given that its vapour density is 29, find its molecular formula.
[C = 12, H = 1]
Calculate the relative molecular mass of:
CH3COONa
The mass of 5.6 litres of a certain gas at S.T.P. is 12 g. What is the relative molecular mass or molar mass of the gas?
Ammonia burns in oxygen and the combustion, in the presence of a catalyst, may be represented by;
\[\ce{2NH3 + 2 1/2O2 -> 2NO + 3H2O}\] [H = 1, N = 14, O = 16]
What mass of steam is produced when 1.5 g of nitrogen monoxide is formed?
