CBSE
Multiple Choice QuestionsIf the first ionization energy of H atom is 13.6 eV, then the second ionization energy of He atom is:
27.2 eV
40.8 eV
54.4 eV
108.8 eV
The liquefied metal expanding on solidification is
Ga
Al
Zn
Cu.
The atomic number of cerium (Ce) is 58. The correct electronic configuration of Ce3+ ion is.
[Xe] 4f1
[Kr] 4f1
[Xe] 4f13
[Kr] 4d1
Assertion : Barium is not required for normal biological function in human.
Reason : Barium does not show variable oxidation state.
If both assertion and reason are true and the reason is the correct explanation of the assertion.
If both assertion and reason are true and the reason is not the correct explanation of the assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The compound insoluble in water is
mercurous nitrate
mercuric nitrate
mercurous chloride
mercurous perchlorate.
Which of the follownig elements, is most electronegative ?
F
O
Ne
Na
Which of the following is correct?
Radius of Ca2+ < Cl- < S2-
Radius of Cl- < S2- < Ca2+
Radius of Cl- = S2- = Ca2+
Radius of S2- < Cl- < Ca2+
The decreasing order of basic character of K2O, BaO, CaO and MgO is
K2O > BaO > CaO > MgO
K2O > CaO > BaO > MgO
MgO > BaO > CaO > K2O
MgO > CaO > BaO > K2O
Which one of the following has the lowest ionisation energy?
1s2 , 2s2 , 2p6
1s2 , 2s2 , 2p6 , 3s1
1s2 , 2s2 , 2p5
1s2 , 2s2 , 2p3
Metal ion responsible for the Minimata disease is
CO2+
Hg2+
Cu2+
Zn2+
