Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : In expensive scientific instruments, silica gel is kept in watch-glasses or in semipermeable membrane bags.
Reason (R) : Silica gel adsorbs moisture from air via adsorption, thus protects the instrument from water corrosion (rusting) and / or prevents malfunctioning.
In the light of the above statements, choose the correct answer from the options given below :
Match List I with List II
List I (molecules/ions) |
List II (No. of lone pairs of e$$^-$$ on central atom) |
||
---|---|---|---|
A. | $$\mathrm{IF_7}$$ | I. | Three |
B. | $$\mathrm{ICl}$$$$_4^ - $$ | II. | One |
C. | $$\mathrm{XeF_6}$$ | III. | Two |
D. | $$\mathrm{XeF_2}$$ | IV. | Zero |
Choose the correct answer from the options given below :
Lithium aluminium hydride can be prepared from the reaction of :
The alkaline earth metal sulphate(s) which are readily soluble in water is/are :
A. $$\mathrm{BeSO}_{4}$$
B. $$\mathrm{MgSO}_{4}$$
C. $$\mathrm{CaSO}_{4}$$
D. $$\mathrm{SrSO}_{4}$$
E. $$\mathrm{BaSO}_{4}$$
Choose the correct answer from the options given below :