Principles Related to Practical Chemistry · Question 15

A salt with few drops of conc. HCl gives apple green colour in flame test. The group precipitate of the salt is dissolved in acetic acid and treated with K2CrO4 to give yellow precipitate. When the sodium carbonate extract of the salt solution is heated with conc. HNO3 and ammonium molybdate, it resulted a canary yellow precipitate. The cation and anion present in the salt are respectively,

1. Ca2+ and SO42-
2. Ba2+ and PO43-
3. Mn2+ and PO43-
4. Ba2+ and SO42-

Complete combustion of X g of an organic compound gave 0.25 g of CO2 and 0.12 g of H2O. If the % of carbon is 25% and of hydrogen is 4.89%, then X = 10-3 g. (Nearest integer) (Molar mass of C, H and O are 12, 1 and 16 g mol-1 respectively.)

1. 273
2. 27
3. 2730
4. 227

Method used for separation of mixture of products (B and C) obtained in the following reaction is [figure]

1. simple distillation
2. sublimation
3. fractional distillation
4. steam distillation

Given below are two statements: In the light of the above statements, choose the correct answer from the options given below

1. Statement I is true but Statement II is false
2. Both Statement I and Statement II are false
3. Statement I is false but Statement II is true
4. Both Statement I and Statement II are true

0.53 g of an organic compound (x) when heated with excess of nitric acid (concentrated) and then with silver nitrate gave 0.75 g of silver bromide precipitate. 1.0 g of (x) gave 1.32 g of CO2 gas on combustion. The percentage of hydrogen in the compound (x) is %. [Nearest Integer] [Given: Molar mass in g mol-1 H : 1, C : 12, Br : 80, Ag : 108, O : 16; Compound (x) : CxHyBrz]

A student has been given 0.314 g of an organic compound and asked to estimate sulphur. During the experiment, the student has obtained 0.4813 g of barium sulphate. The percentage of sulphur present in the compound is . (Given molar mass in g mol-1 S : 32, BaSO4 : 233)

1. 63.15%
2. 21.05%
3. 48.24%
4. 42.10%

Consider three metal chlorides x, y and z, where x is water soluble at room temperature, y is sparingly soluble in water at room temperature and z is soluble in hot water. x, y and z are respectively

1. AgCl, Hg2Cl2 and PbCl2
2. CuCl2, AgCl and PbCl2
3. AlCl3, PbCl2 and BaCl2
4. MgCl2, AgCl and AlCl3

In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is %. (Aqueous tension at 300 K is 15 mm).

In the Group analysis of cations, Ba2+ & Ca2+ are precipitated respectively as

1. sulphide & sulphide
2. hydroxide & carbonate
3. chromate & sulphide
4. carbonate & carbonate

0.25 g of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of CaCl2 tube and potash tube at the end of the experiment. The amount was found to be 0.15 g and 0.1837 g, respectively. The percentage of oxygen in compound A is %. (Nearest integer) (Given: molar mass in g mol-1 H : 1, C : 12, O : 16)