ICSE − Q & A

a gas cylinder of capacity 20dm3 is filled with gas X the mass of which is 10 g .when the same cylinder is filled with hydrogen gas at the same temperature and pressure the mass of hydrogen is 2g ,hence cal the relative molecular mass of the gas.
show working pls

Plz explain sterio isomerism with an example

I have some doubts:
1)State the group number of the group number of  the group which has 3 columns of elements.
2)Name an acid solid in nature.
3)Is Iron(II) Sulphate soluble in water?
4)What is the molecular formula of sodium zeolite?Is it soluble in water?
5)Is the colour of Iron (III) Chloride reddish-brown or yellow?
6)Viraf J Dalal workbook Pg 42 3.(6) Solid sodium chloride contains ions ryt(they havent mentioned free anywhere)
7)Name a nonmetal which volatizes at low temperatures and burns with a pale blue flame.(Is this hydrogen?)
8)Starting from aluminium how would u prepare a dil. acid which gives a white ppt with barium sulphate the precipitate being insoluble in all dil. acids?(Isnt BaSO4 already a ppt?)
9)Which gas turns alkaline pyrogallol soln brown?Cud u give a rxn if possible?
10)Zinc is used in voltaic cells as  cathode.In voltaic cells cathode means +ve  terminal right?
11)Which alloy of copper is used in hardware and scientific instruments?
12)Which alloy of aluminium is used to make the beams of a balance?
13)Why is amalgamated sodium preferred to  normal sodium for preparation of hydrogen?
14)Why is zinc added to copper in the right proportion for manufacture of screws?
15)Electric wires of nichrome are preferred to copper wires for specific applications.Give Reason.
Cud someone pls answer these questions?

name the gas that is most en among  all the elements

Plzz answer them
1)State the reaction when a candle in burnt in a jar full of chlorine
2)State the obsveration when a defragating spoon with burning turpentine is lowered                           into a jar of chlorine.
3)Give reason why sulphur dioxide and not chlorine must be used for bleaching silk
$)Name a colourless gas(other than oxygen) which rekindles a glowing splinter.

Can u give d reaction for ammonium dichromate being heated?

I guess u all should use ur gmail account instead of having a respaper account ......b careful of people around u...

why is sai taking my name for sdfg? i didnt trouble him....jst one boy messaged me that real name of sdfg is xyz,so i got excited i commented in q and ans column.i am sorry for that too

- whats the test for nitrogen 
 - whats the observation of reduction of CuO using ammonia?

Which element has the highest electron affinity?
(I know its Chlorine, but accor. to trend, it should be fluorine. So what to write?

Also, Zn forms anode/cathode of dry cell?
(Accor. to Viraf Dalal TB, its cathode, but on google, its anode everywhere!!)