Principles Related to Practical Chemistry

Using the given figure, the ratio of Rf values of sample A and sample C is x 10-2. Value of x is . [figure]

In the precipitation of the iron group (III) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to :

1. decrease concentration of -OH ions
2. increase concentration of Cl- ions
3. prevent interference by phosphate ions
4. increase concentration of NH4+ ions

Which of the following nitrogen containing compound does not give Lassaigne's test ?

1. Glycine
2. Phenyl hydrazine
3. Urea
4. Hydrazine

When MnO2 and H2SO4 are added to a salt (A), a greenish yellow gas is liberated. The salt (A) is :

1. NH4Cl
2. CaI2
3. KNO3
4. NaBr

The adsorbent used in adsorption chromatography is/are - Choose the most appropriate answer from the options given below :

1. C and D only
2. A only
3. B only
4. A and B only

In Kjeldahl's method for estimation of nitrogen, CuSO4 acts as :

1. catalytic agent
2. hydrolysis agent
3. reducing agent
4. oxidising agent

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

1. Both Statement I and Statement II are correct
2. Statement I is incorrect but Statement II is correct
3. Both Statement I and Statement II are incorrect
4. Statement I is correct but Statement II is incorrect

The number of white coloured salts, among the following is (a) SrSO4 (b) Mg(NH4)PO4 (c) BaCrO4 (d) Mn(OH)2 (e) PbSO4 (f) PbCrO4 (g) AgBr (h) PbI2 (i) CaC2O4 (j) [Fe(OH)2(CH3COO)]

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

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

Lassaigne's test is used for detection of :

1. Phosphorous and halogens only
2. Nitrogen, Sulphur and Phosphorous only
3. Nitrogen, Sulphur, phosphorous and halogens
4. Nitrogen and Sulphur only