Question

what characteristic do alkaline earth metals share? *
they have 1 valence electron
they are gases at room temperature
they are white or silvery and malleable
they are non-reactive
what is the atomic weight of potassium? *
40
29
39
50
in group 13 (boron family), what element is classified as a metalloid? *
boron
aluminum
gallium

Explanation:

First Sub - Question: What is the atomic weight of Potassium?

Step1: Recall Potassium's atomic weight

Potassium (K) has an atomic weight of approximately 39.10, and among the given options (40, 29, 39, 50), 39 is the closest approximation.

Alkaline Earth Metals are in Group 2 of the periodic table. They have 2 valence electrons (not 1, so the first option is wrong). They are solids at room temperature (so the "gases at room temperature" option is wrong). They are reactive (so "non - reactive" is wrong). They are typically white or silvery and malleable, which matches the option "They are white or silvery and malleable".

In Group 13, Boron (B) is a metalloid. Aluminum and Gallium are metals.

Answer:

39

Second Sub - Question: What characteristic do Alkaline Earth Metals share?