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An organic compound gave the following results on analysis. C = 53.3%, H = 15.6%, N = 31.1%. Find molecular formula of compound. (Molecular Weight = 45)
An organic compound contains C, H and O in the proportion of 6 : 1 : 8 by weight, respectively. Find its molecular formula (V.D = 30)
Elements No. of moles Simple ratio C 6/12 = 0.5 1 H 1/1 = 1 2 O 8/16 = 0.5 1 $ \therefore E.F = CH_2O $ M.W = 2VD =60 $ \therefore n = 2 \therefore M.F = C_2H_4O_2 $
0.2595 gm of organic substance gave 0.35 gm $ BaSO_4$ . Find % S in the substance.
$ \% S = { 32 \over 233} \times { 0.35 \over 0.2595} \times 100 = 18.52 $
Find the incorrect formula
The incorrect formula among the given options is: \( \%C = \frac{12 \times m \times 100}{44 \times V} \)
Explanation: The correct formula to calculate the percentage of carbon is \(\%C = \frac{12 \times m}{44 \times V} \times 100\), where \(m\) is the mass of CO$_2$ and \(V\) is the volume of the gas. The given formula includes an extra multiplication by \(m\) and hence is incorrect.
On complete combustion, 0.246g organic substance gave 0.198 g $CO_2 and 0.1014 g H_2O $ . Find % of C and H in compound ?
To find the percentage of C and H in the compound, we need to perform the following calculations:
Calculate the mass of carbon in CO$_2$: \[ \text{Mass of C} = \frac{12}{44} \times 0.198 \text{ g} = 0.054 \text{ g} \]
Calculate the mass of hydrogen in H$_2$O: \[ \text{Mass of H} = \frac{2}{18} \times 0.1014 \text{ g} = 0.0113 \text{ g} \]
Calculate the percentage of C and H in the organic compound: \[ \%C = \frac{0.054}{0.246} \times 100 = 21.95\% \] \[ \%H = \frac{0.0113}{0.246} \times 100 = 4.58\% \]
Hence, the correct percentages of C and H are 21.95% and 4.58%, respectively. Therefore, the correct option is 21.95, 4.58.
Which of the following is the method of estimating nitrogen in organic Compound ?
Both the Dumas and Kjeldahl methods are used for estimating nitrogen in organic compounds. The Dumas method involves combustion of the compound and measuring the nitrogen gas released, while the Kjeldahl method involves digestion of the compound with a strong acid and measuring the ammonia produced.
In the Dumas method nitrogen containing organic compound is first heated with
In Dumas method the gaseous mixture produced is passed through $ KOH_{(aq ). As a result of this _______ is absorbed in KOH_{(aq)} $ .
In the Dumas method, the gaseous mixture produced is passed through aqueous potassium hydroxide (KOH). The $CO_2$ in the gaseous mixture is absorbed by the KOH, allowing nitrogen gas to be measured accurately.
In Dumas method the formula of % N is
In Dumas method, the formula for calculating the percentage of nitrogen (% N) in an organic compound is given by: \[ \% N = \frac{28 \times V \times 100}{22400 \times m} \] where:
In Dumas method for estimation of nitrogen, 0.3g of an organic compound gave 50 ml of nitrogen collected at 300K temperature and 715 mm pres sure. Calculate the % of N in the compound. ( Aqueous tension at 300K = 15mm)
P = 715 - 15 = 700 mm $ Vol of N_2 at STP = { 273 \times 700 \times 50 \over 300 \times 760} = 41.9 ml $ $ \therefore \% N = { 28 \times 41.9 \times 100 \over 22400 \times 0.3 } = 17.46 \% $
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