Which one of the following statements is not correct?
The hydration enthalpies of alkali metal ions decrease down the group.
LIthium halides are some what covalent in nature
Alkali metals react with water liberating oxygen gas
KO2 is paramagnetic.
Identify the statement which is not correct?
Dehydrobrominaton of 2-bromopentane gives pent-1-ene as the major product
Freon 12 is manufactured by Swarts reaction
CHCl3 is stored in closed, dark coloured bottles
Chronic exposure to CHCl3 causes liver damage
The gaseous products formed at cathode (X) and anode (Y), when an aqueous solution of sodium acetate is electrolysed are
X | Y |
CO2 | C2H6, H2 |
X | Y |
H2, CO2 | C2H6 |
X | Y |
H2 | C2H6, CO2 |
X | Y |
C2H6, H2 | CO2 |
Identify the correct statements from the following
(i) Electromeric effect is a permanent effect
(ii) Hyper conjugation is a temporary effect
(iii) Fractional distillation is used to separate two liquids from a mixture if the difference in their boiling points is less
(iv) Different compounds are adsorbed on an adsorbent different extents
ii, iii, iv
i, ii, iii
ii, iv
iii, iv
Identify the correct statements for a ring system to exhibit aromaticity
(i) It must not be planar
(ii) The ring must contain (4n+ 2)Π electrons.
(iii) The ring must be planar.
(iv) It must possess 4n Π electrons.
The correct answer is:
ii, iv
i, ii
i, iv
ii, iii
Identify, from the following, the diamagnetic, tetrahedral complex
[Ni(Cl)4]2-
[Co(C2O4)3]3-
[Ni(CN)4]2-
[Ni(CO)4]
To prepare XeF6. Xe and F2 are mixed at 573 K and 60-70 bar in the ratio of
20:1
1:5
5:1
1:20
D.
1:20
Xenon hexafluoride (XeF6) is formed by taking Xe and fluorine in ratio of 1:20 under pressure of 70 bar and 573 K temperature.
Which one of the following solutions of compounds show highest osmotic pressure?[AB, AB2,A2B3 are ionic compounds]
5.0 M urea i= 10 and temperature is 67°C
1.5M A2B2 type i= 41 temperature is 27°C
3.0 M AB type i= 16 and temperature is 27°C
2.5 M AB2 type i = 2.5 and temperature is 57°C.