is positive for
I. LiF
II. CsI
III. RbF
IV. KF
(1) I, II, III & IV
(2) II only
(3) I only
(4) I & II only
Gypsum on heating can change to :
1. Orthorhombic form.
2. Plaster of paris.
3. Dead plaster.
4. All of the above.
The cation of alkali metals are found as M(H2O)+n in H2O.
The value of 'n' is maximum for -
1. Na+
2. K+
3. Rb+
4. Li+
The fire extinguisher contains NaHCO3 and the compound (X). The compound (X) maybe -
1. CH3COOH
2. NaOH
3. C6H5OH
4. None of the above.
All group-2 metals dissolve in liquid ammonia to produce a bright blue colour. The colour is due to-
1. A change in the structure of ammonia.
2. d-d transition.
3. The spectrum of the solvated electrons.
4. An electronic transition from a lower to a higher energy state.
A substance that gives a brick red flame and breaks down on heating giving oxygen and a brown gas is-
1. Calcium carbonate.
2. Magnesium carbonate.
3. Magnesium nitrate.
4. Calcium nitrate.
Which of the alkali metal chloride (MCl) forms its dehydrate (MCl.) easily?
1. LiCl
2. CsCl
3. RbCl
4. KCl
Crude sodium chloride obtained by crystallization of brine solution does not contain-
1.
2.
3.
4.
A: Alkali metals can be extracted by chemical reduction
R: Alkali metals are weak reductants.
1. Both Assertion & Reason are true and the reason is the correct explanation of the assertion.
2. Both Assertion & Reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is a true statement but Reason is false.
4. Both Assertion and Reason are false statements.
The bleaching action of bleaching powder is due to the formation of :
1.
2.
3.
4.