more than one correct ino

Q1Boron readily dissolves in
a)conc HCl
b)fused NaOH at 673K
c)fused Na2CO3 +NaNO3 at 1173K
d)mixture of conc. HNO3 and conc. H2SO4 (1:2)

Q2 Nitrogen can combine at higher temp directly to give nitrides with
a)Mg
b)Al
c)Zn
d)Fe

Q3 Which is inocrrect representation of dithionate ion ?

12 Answers

156
Rajiv Agarwal ·

I think the answers should be:

1. a, b, c

2. a, b

3. Dithonate ion has a S-S bond...both S atoms are in the +5 oxidation state. Option (b) is correct

24
eureka123 ·

ans1,3 is wrong...

ans 2 is rite...can u give me reactions ??

156
Rajiv Agarwal ·

For Question 3 -I am absolutely sure that dithionate ion has the structure as given in option (b)

For Question 2, Mg3N2 & AlN are the two compounds that are formed. One needs highly electropositive metals for the formation of nitrides. Transition metals don't form nitrides in general.

For Q.1 - Let me check. Sure about Reactions 1 & 2 occurring... BCl3 & Borax are formed. Reaction 3 needs to be checked.

39
Pritish Chakraborty ·

Rajiv is right about question 3...that IS the dithionate ion..what makes you think otherwise, eure?
Achcha...now your question is to find the incorrect representations..lol. Ans a,c,d then.

24
eureka123 ·

hehe ..ok ...looks like sir misunderstood teh ques and i misunderstood him...btw i still ahve dbt in strucure b)

dithionic acid looks like this naa ???

so how double bonds broken ...that too all ???

1
aieeee ·

Q.3) Either its a printing mistake in the question or its trying to confuse us by giving the skeletal structures and representing every bond as a single bond.

1
aieeee ·

Q.1) Answer is a , b and d.

a) B is not affected by conc. HCl in pure form at room temperatures, though, it shows some reactions with conc. HCl at very high temperatures.

2 B + 6HCl → 2BCl3 + 3H2

b) 2 B + 6 NaOH → 2 Na3(BO3) + 3H2

c) I hv not read abt such thing

d) Ya, this reaction takes place as the mixture of conc. HNO3 and conc. H2SO4 (1:2) acts as a very strong oxidising agent for B. this is also carried out by H2O2.

Q.2) The ans. is surely a and b.

Mg3N2 and AlN are formed. also, this reaction is shown by Li of group - 1 metals.

39
Pritish Chakraborty ·


This is sodium dithionate..now you can judge for yourselves.

24
eureka123 ·

@ pritish cant see the image dude...

@ aieeee
ans1=c,d

1
aieeee ·

i can't say whether ' c ' is correct or not. but, a and b are certainly correct , as per J.D.Lee.

i hv also given the reactions involved .

24
eureka123 ·

ya i read that,,,.....maybe my book answer key may be wrong....but can u recheck once more plz ..

1
aieeee ·

k. i'll check it again.

Your Answer

Close [X]