Question

storyline 1 exam
which arrangement of the following period 5 elements, from left to right, orders them with respect to their atomic size, from smallest to largest?
○ rb, sr, in, sb, te
○ in, sb, te, rb, sr
○ in, rb, sb, sr, te
○ te, sb, in, sr, rb

Explanation:

Atomic size (atomic radius) decreases across a period (from left to right) in the periodic table. This is because as we move from left to right across a period, the number of protons in the nucleus increases (increasing the positive charge), and electrons are added to the same principal energy level. The increased nuclear charge pulls the electrons closer to the nucleus, reducing the atomic size.

For Period 5 elements:

• \(Rb\) (Rubidium) is on the far left of the period among the given elements.
• \(Sr\) (Strontium) is to the right of \(Rb\).
• \(In\) (Indium) is further to the right.
• \(Sb\) (Antimony) is to the right of \(In\).
• \(Te\) (Tellurium) is the right - most among the given elements.

So, the order from smallest to largest atomic size (i.e., from right to left in the period) is \(Te\), \(Sb\), \(In\), \(Sr\), \(Rb\).

Answer:

Te, Sb, In, Sr, Rb