19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Which of the following test is used for quantitative estimation of N
An organic compound having carbon, hydrogen and sulphur contains 4% of sulphur. The minimum molecular weight of the compound is
In a Dumas nitrogen estimation 0.3 g of an organic compound gave 50 cm3 of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the compound (vapour pressure of water at 300K is 15 mm) is
A mixture of benzene and chloroform is separated by–
How will you purify a liquid having non-volatile impurities?
Which of the following compound is/are purified by sublimation?
How will you separate iodine from sodium chloride?
An organic liquid decomposes below its boiling point. How will you purify it?
The best method for the sepration of naphthalene and benzoic acid from their mixture is
The separation of the constituents of a mixture by column chromatography depends upon their
A mixture of acetone and CCl4 can be separated by
Azeotropic distillation is used only to seperate azeotropes ie. constant boiling mixture. Here acetone & CCl4 are not azeotropic mixture. Hence (a) is not correct.
CCl4 & acetone differ in their boiling Point. So it can be seperated through fractional distillation. Hence (b) is correct.
Steam distillation is used only in case of steam volatile substance. Hence (c) is not correct. 4. Vaccum distillation is used in liquids which decompose at their boiling Point. Hence (d) is incorrect.
Anthracene can be purified by
Assertion (A): During test for nitrogen with Lassaigne’s extract on adding FeCl3 solution sometimes a red precipitate is obtained. Reason (R): Sulphur is also present (AIIMS2007)
Assertion (A): Oils are purified by steam distillation. Reason (R): The compounds which decompose at their boiling points can be purified by steam distillation. (AIIMS2008)
Assertion (A): S || NH – C– NH gives red color in Lassaigne’s test Reason (R): Compounds having N along with C give red colour in Lassaigne’s test. (AIIMS2009)
A hydrocarbon has carbon and hydrogen. Its molecular weight is 28. Its possible formula would be (AFMC 2009) (a) C H (b) C H (c) CH (d) C H Ans. (b) Sol. Compound Molecular weight C H 12 3 x C H x CH C H x Henc…
In an organic compound, C 68.5% and H 4.91% . Which empirical formula is correct for it? (CPMT 2009) (a) C H (b) C H O (c) C H O (d) C H O Ans. (b) Sol. Element At. Percent No. of Simple molar wt. composition moles …
In the Duma's method of estimation of nitrogen, the nitrogen in the organic compound is finally converted into (Kerala CEE 2009)
The masses of carbon, hydrogen and oxygen in an organic compound are in the ratio 6: 1: 8 respectively. Which of the following pairs of formulae correspond to the above information? (Kerala CEE 2009) (a) CH O and CH …
1 percent composition of an organic compound A is carbon: 85.71% and hydrogen 14.20% . Its vapour density is 14. Consider the following reaction sequence Cl /H O (i) KCN/EtOH (ii) H O A B C -> -> Identify C (EAMCET 2…
A hydrocarbon contains 80% carbon. What is the empirical formula of the compound? (KCET 2009 )
Which of the following compounds gives blood red coloration when it Lassaigne’s extract is treated with alkali and ferric chloride? (DPMT 2009)