CuSO4 (aq.)MN+O
Then final products N and O are respectively.
1. [Cu(CN)4]3-,(CN)2
2. CuCn,(CN)2
3. [Cu(CN)4]2-,(CN)2
4. Cu(CN)2,K2S
Difficulty Level:
CrO42- (yellow) changes to Cr2O72- (orange) in pH =x and vice versa in pH=y. Hence, x and y are:
1. 6,8
2. 6,5
3. 8,6
4. 7,7
Difficulty Level:
When steam is passed over red hot iron , the substances formed are:
1. Fe2O3 +H2
2. Fe3O4 +H2
3. FeO +H2
4. FeO+ H2 +O2
Difficulty Level:
Which of the following solid salt on heating with K2Cr2O7 and Conc. H2SO4 orange,red vapours are evolved which turn aquous NaOH solution yellow?
1. NaBr
2. NaCl
3. NaNO3
4. NaI
Difficulty Level:
Fe is made passive by :
1. dil . H2SO4
2. dil. HCl
3. Conc. HNO3
4. Conc. H2SO4
Difficulty Level:
The iron salt used in blue prints is:
1. FeC2O4
2. Fe2(C2O4)3
3. K4Fe(CN)6
4. FeSO4
Difficulty Level:
Which has highest melting point?
1. Cr
2. Fe
3. Cu
4. Mo
Difficulty Level:
The colour of KMnO4 is due to
1. d-d transition
2. Charge transfer spectra
3. Polarisation of ion
4. p-d transition
Difficulty Level:
Which of the following element does not show the variable oxidation state?
1. Fe
2. Mn
3. Cu
4. Zn
Difficulty Level:
With F highest stable oxidation state of Mn is
1. +6
2. +4
3. +7
4. +3
Difficulty Level: