Consider the following data, what is the general trend for the atomic radius of these elements across the period? Note: the

Question

second row in the table is the atomic radius and the first number above the symbol is the atomic number.
19
K
20
Ca
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
227 197 122 123 125 117 114 112
(1 point)
Increasing
Decreasing
Remains the same

Answer 1

The atomic radius generally decreases as you move from left to right across a period in the periodic table. This is due to the increasing nuclear charge, which pulls the electron cloud closer to the nucleus, resulting in a smaller atomic radius.

In the provided data, the atomic radii of the elements decrease from potassium (K) to krypton (Kr):

• K: 227 pm
• Ca: 197 pm
• Ga: 122 pm
• Ge: 123 pm (slightly increases, but this is still consistent with the trend as it transitions between p-block elements)
• As: 125 pm
• Se: 117 pm
• Br: 114 pm
• Kr: 112 pm

Despite the slight fluctuations, the overall trend is a decrease in atomic radius. Therefore, the general trend across the period is Decreasing.