Which of the following statement$(s)$ is/are incorrect?

  • A
    Mendeleev's periodic law was based on atomic number of the element.
  • B
    Effective nuclear charge $(Z_{eff})$ = atomic mass $-$ shielding constant.
  • C
    Mulliken's value of electronegativity of an element is about $2.8$ times lesser than the Pauling scale.
  • D
    All of these.

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Similar Questions

Which of the following order$(s)$ is/are correct?
$(1) Li < Be < B < C$ $(IE_1)$
$(2) Li < Na < K < Rb < Cs$ (Reducing power in gaseous state)
$(3) Li^{+} < Na^{+} < K^{+} < Rb^{+} < Cs^{+}$ (Ionic mobility in aqueous solution)
$(4) S > Se > Te > O$ $(EA)$

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Which of the following orders is correct for the property mentioned in brackets?

Which of the following statements are correct?
$A.$ The process of the addition of an electron to a neutral gaseous atom is always exothermic.
$B.$ The process of removing an electron from an isolated gaseous atom is always endothermic.
$C.$ The $1^{st}$ ionization energy of boron is less than that of beryllium.
$D.$ The electronegativity of $C$ is $2.5$ in $CH_4$ and $CCl_4$.
$E.$ $Li$ is the most electropositive among elements of group $I$.
Choose the correct answer from the options given below:

Match List-$I$ with List-$II$:
List-$I$ (Atomic Number) List-$II$ (Block of periodic table)
$A$. $37$ $I$. $p$-block
$B$. $78$ $II$. $d$-block
$C$. $52$ $III$. $f$-block
$D$. $65$ $IV$. $s$-block

Choose the correct answer from the options given below:

Identify the correct statements from the following.
$(i)$ In the periodic table,about $78 \%$ of elements are metals.
$(ii)$ In a group,the metallic character decreases from top to bottom and in a period the nonmetallic character decreases from left to right.
$(iii)$ The element $Ho$ belongs to $f-$block.

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