Question

For elements 1-20, we can use the periodic table to predict.

Answer 1

Answer:

B

Explanation:

because a periodic table shows the arrangement of element according to their atomic number and their valence neither

isotopes nor colour

Answer 2

Answer:

B.

Explanation:

We can predict the number of valence electrons  by which group of the Periodic table an element resides.

For example Lithium is in group 1  and has 1 valency electron.