Answer:
A
Explanation:
I think this is true letter a
Answer:
(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.
Answer:
The number of electrons in the outermost shell of an atom determines its reactivity. Noble gases have low reactivity because they have full electron shells. Halogens are highly reactive because they readily gain an electron to fill their outermost shell.
Explanation:
Answer:
Molecules are made of atoms.
