Question
- How does Ionic radii vary with effective nuclear charge? Give example.
- An element belongs to 3rd period and group-13 of the periodic table. Identify the element and write two properties of element.
✓
Answer
a. Ionic radii decreases as effective nuclear charge increases e.g. $\mathrm{Mg}^{2+}$ is smaller than $\mathrm{Na}^{+}$because $\mathrm{Mg}^{2+}$ has 12 protons which attract 10 electrons more strongly than 1 electrons attract 10 electrons in $\mathrm{Na}^{+}$.
- Inverse proportion to the effective nuclear charge.
- Direct proportion to the screening effect.
b. It is aluminum, good conductor of electricity, solid and metallic.
- Inverse proportion to the effective nuclear charge.
- Direct proportion to the screening effect.
b. It is aluminum, good conductor of electricity, solid and metallic.
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