Give the ground-state electron configuration for each of the following elements. After each atom is its atomic number in parentheses. (a) Potassium (19) (b) Neon (10)How many electrons are in the valence shell of each atom ? (a) Visited um (AI) (b) Oxygen (O) (c) Fluorine (F)

(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

(b) ₁₀Ne: 1s² 2s² 2p⁶

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(a) 3

(b) 6

(c) 7

Explanation:

We can state the ground-state electron configuration for each element following Aufbau's principle.

(a) ₁₉K: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

(b) ₁₀Ne: 1s² 2s² 2p⁶

Second part

(a) Al belongs to Group 13 in the Periodic Table. It has 13-10=3 electrons in the valence shell.

(b) O belongs to Group 16 in the Periodic Table. It has 16-10=6 electrons in the valence shell.

(c) F belongs to Group 17 in the Periodic Table. It has 17-10=7 electrons in the valence shell.

i think it is d. e because the next one is igneous.

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms