Solubility products of Al(OH)3 and Zn(OH)2 are 8.5 × 10-23 and 1.8 × 10-4 respectively. If both Al3+ and Zn2+ ions are present in a solution, which one will be precipitated first on addition of NH4OH?
Al(OH)3
Zn(OH)2
Both (a) and (b)
None of these
In a reversible isothermal process, the change in internal energy is
zero
positive
negative
None of these
Based on the following thermochemical equations
H2O (g) + C(s) → CO (g) + H2 (g); H = 131 kJ
CO (g) + O2(g) → CO2 (g); H = -282 kJ
H2 (g) + O2 (g) → H2O (g); H =-242 kJ
C (s) + O2 (g) → CO2 (g); H = X kJ
the value of X will be
-393 kJ
-655 kJ
+393 kJ
+655 kJ
The first ionisation potential of Na, Mg, Al and Si are in the order
Na < Mg > Al < Si
Na > Mg > Al > Si
Na < Mg < Al > Si
Na > Mg > Al < Si
Elements of which group form anions most readily?
Oxygen group
Nitrogen group
Halogens
Alkali metals
Which of the following is paramagnetic?
[Ni(CO)4]2+
[Co(NH3)6]2+
[Ni(CN)4]2-
[NiCl4]2-
B.
[Co(NH3)6]2+
D.
[NiCl4]2-
Among the given options, option b and d are the correct answers.