MCQ
Which of the following element has smallest size?
- A$K$
- ✓$Sr$
- C$Rb$
- D$Ba$
✓
Answer
Correct option: B.
$Sr$
b
As you go across a period, electrons are added to the same energy level. At the same time, protons are being added to the nucleus. The concentration of more protons in the nucleus creates a higher effective nuclear charge, In other words, there is a stronger force of attraction pulling the electrons closer to the nucleus resulting in a smaller atomic radius. So, all these elements belong to the $4^{th}$ group and $K r$ has the smallest atomic radii as it lies across the period.
As you go across a period, electrons are added to the same energy level. At the same time, protons are being added to the nucleus. The concentration of more protons in the nucleus creates a higher effective nuclear charge, In other words, there is a stronger force of attraction pulling the electrons closer to the nucleus resulting in a smaller atomic radius. So, all these elements belong to the $4^{th}$ group and $K r$ has the smallest atomic radii as it lies across the period.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Which of the following has $ds{p^2}$ hybridization
→$(MCPBA \to$ meta-chloro perbenzoic acid)
Stereochemistry of the product of above reaction is
→Stereochemistry of the product of above reaction is
The following compound will undergo electrophilic substitution more readily than benzene
Among the following, which has the lowest enthalpy of fusion ?
What electrolyte is used to electroplate silver onto a spoon?
Concentration of a gas is expressed in the following terms in the calculation of equilibrium constant
In which of following option is wrong about stability of diatomic molecules
Which of these are particulates?
$1.520\, g$ of the hydroxide of a metal on ignition gave $0.995\, gm$ of oxide. The equivalent weight of metal is
→Element showing the phenomenon of allotropy is: