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.
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.
Gypsum on heating can change to :
1. Orthorhombic form.
2. Plaster of paris.
3. Dead plaster.
4. All of the above.
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
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+
on heating (below 200 degrees celsius) liberates a gas. The same gas will be obtained below 600 degrees celsius by :
1. Heating
2. Heating
3. Heating
4. None of the above
The incorrect statement among the following is :
1. The atomic radius of Na is greater than that of Mg.
2. Density of K is more than Na.
3. Melting point & boiling point of Ca are greater than those of Mg.
4. Mg does not react with cold water.
A Brine solution on electrolysis will not give :
1. NaOH
2.
3.
4.