CLASS - XI CHEMISTRY (Classification of Elements and Periodicity in Properties) work sheet-3

Topic: - Trends in physical properties of elements

1. Predict the position of the element in the periodic table satisfying the
electronic configuration (n-1) d1 ns2 for n=4,

2. How does atomic size change in a group?

3. Why Li and Mg show resemblance in chemical behaivour?

4. The atomic radius of elements decreases along the period but Neon has highest
size among III period element? Why

5. Explain why cations are smaller and anions are larger in radii than their parent
atom?

6. Define ionization enthalpy and electron gain enthalpy?

7. How does atomic size change in a group?

8. The size of an atom can be expressed by three radii. Name them. Which of
these given the highest, and the lowest value of the atomic radius of an element?

9. Among the elements B, Al, C and Si
(a) Which has the highest first ionization enthalpy?
(b) Which has the largest atomic radius?

8. Na+ has higher value of ionization enthalpy than Ne, though both have same
electronic configuration.