Single Choice

The electronic states $$X$$ and $$Y$$ of an atom are depeicted below: $$X : 1s^{2} 2s^{2} 2p^{6} 3s^{1}$$ $$Y: 1s^{2} 2s^{2} 2p^{6} 3s^{2} 3p^{6} 4s^{1}$$ Which of the following statements is not correct?

A$$X$$ represents an alkali metal.
BEnergy is required to change $$X$$ into $$Y$$
C$$Y$$ represents ground state of the element.
DLess energy is required to remove an electron from $$X$$ than from $$Y$$
Correct Answer

Solution

Electronic configuration for given elements X =1s22s22p63s1,Y=1s22s22p63s23p64s1
shows that they belong to the same group (group 11, alkali metals) and Y is bigger in size than X. Thus, the distance between the nucleus and valence shell in Y is greater as compared to X and therefore Y experience less effective nuclear charge and needs less energy to remove the valence electron than that from X atom.

SIMILAR QUESTIONS

Periodic Classification of Elements

Green house effect is caused by :

Periodic Classification of Elements

Ionization energy of gaseous $$Na$$ atoms is $$495.5$$ kJ mol$$^{-1}$$. The lowest possible frequency of light that ionizes a sodium atom is: $$[h=6.626\times 10^{-34} \ Js, N_A=6.022\times 10^{23} \ mol^{-1}]$$

Periodic Classification of Elements

For the second period elements the correct increasing order of first ionisation enthalpy is:

Periodic Classification of Elements

Ionizing radiation is:

Periodic Classification of Elements

Energy of an electron in the ground state of the hydrogen atom is $$-2.18\displaystyle \times 10^{-18}J$$. Calculate the ionization enthalpy of atomic hydrogen in terms of J mol$$\displaystyle ^{-1}$$.

Periodic Classification of Elements

Would you expect the first ionization enthalpies for two isotopes of the same element to be the same or different? Justify your answer.

Periodic Classification of Elements

Which of the following can most easily form unipositive gaseous ion?

Periodic Classification of Elements

Beryllium has higher ionization enthalpy than boron. This can be explained as :

Periodic Classification of Elements

Ionization enthalpies of transition metals are:

Periodic Classification of Elements

Which of the following elements will have highest ionisation energy?

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