19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Camphor is purified by (Kerala PMT 2014)
In the Kjeldahl's method for estimation of nitrogen present in a soil sample, ammonia evolved from 0.75g of sample neutralised 10 mL of 1M H SO . The percentage of nitrogen in the soil is (CBSE AIPMT 2014)
Lassaigne's test is used in qualitative analysis to detect (UK PMT 2014)
In which among the following compounds presence of nitrogen cannot be detected by Lassaigne's method? (MHT CET 2014)
Which one of the following methods can be used to separate a mixture of ortho and para-nitrophenols? (EAMCET 2014)
A liquid which decomposes at its boiling point can be purified by (Manipal 2014)
Correct pair of compounds, which gives blue colouration/ precipitate and white precipitate, respectively, when their Lassaigne’s test is separately done is (West Bengal JEE 2013)
The colour of the solution/precipitate obtained in the elemental analysis of an organic compound and the molecule/ion responsible for the colour are given below. Choose the incorrectly matched pair: (Kerala PET 2013 )
Kjeldahl's method cannot be used for the estimation of nitrogen in (AFMC 2013)
In the estimation of sulphur by Carius method 0.480 g of an organic compound given 0.699g of barium sulphide. The percentage of sulphur in this compound is (atomic masses : Ba = 137.5 = 32 and O = 16) (Kerala PET 2012)
Presence of halogen in organic compounds can be detected by using (UP CPMT 2012)
The Lassiaigne’s extract is boiled with conc. HNO3 while testing for halogens. By doing so it (AIPMT Prelim 2011)
1.2 g of organic compound of Kjeldalization liberaze ammonia which consumes 30 cm3 of 1N HCl. The percentage of nitrogen in the organic compound is (KCBT 2011)
In Duma's method of estimation of nitrogen 0.35 g of an organic compound gave 55 mL of nitrogen collected at 300 K temperature and 715 mm pressure. The percentage composition of nitrogen in the compound would be (Aque…
The Lassaigne's extract is boiled with conc. HNO3 while testing for halogens. By doing so it (CBSE AIPMT 2011)
1.2g of organic compound on Kjeldahlisation liberates ammonia which consumes 30 cm3 of 1N HCl. The percentage of nitrogen in the organic compound is (KCET 2011)
In Duma's method of estimation of nitrogen 0.35 g of an organic compound gave 55 mL of nitrogen collected at 300K temperature and 715 mm pressure. The percentage composition of nitrogen in the compound would be (Aqueo…
The Lassaigne's extract is boiled with conc. HNO3 while testing for halogens. By doing so it (CBSE AIPMT 2011)
Which of the following compounds will not give answer Lassaigne’s test for nitrogen (DPMT 2010)
In Carius method of estimation of halogens, 0.099 g organic compound gave 0.287. The percentage of chlorine in the compound will be (Haryana PMT 2010)
0.765 g of an acid gives 0.535 g of CO2 and 0.138 g of H2O. Then, the ratio of the percentage of carbon and hydrogen is (JCECE 2010)
In Kjeldahl's method, ammonia from 5g of food neutralizes 30 cm of 0.1 N acid. The percentage of nitrogen in the food is (KCET 2010)
In an organic compound, phosphorus is estimated as (AFMC 2010) (a) Mg P O (b) Mg PO (c) H PO (d) P O Ans. (a) Sol. In Carius method, the weighed organic compound (containing phosphorus) is heated with conc. HNO foll…
The compound formed in the positive test for nitrogen with the Lassaigne solution of an organic compound is (RPMT 2010) (a) 6 3 Fe Fe(CN) (b) Na Fe(CN) (c) Fe(CN) (d) Na Fe(CN) COS Ans. (a) Sol. 3Na Fe(CN) 4Fe…
Chemical formula of Prussian blue is (AFMC 2010) (a) Na Fe(CN) (b) K Fe(CN) (c) 6 3 Fe Fe(CN)