Cations attain octet structure (8) by losing electron(s) while anions become stable or attains octet structure (8) by gaining electron(s).

The remaining elements are completed as follows to attain octet structure;

Element--valence electron--electrons to gain--electrons to lose--ion formed

O ------------ 6 ---------------------- 2 ------------------------ none -------------- $O^{2-}$

Ca -------- 2 ----------------------- none ---------------------- 2 ------------------ $Ca^{2+}$

Br ----------- 7 --------------------- 1 ------------------------ none --------------- $Br^{-}$

S ------------ 6 ----------------------- 2 ------------------------ none --------------- $S^{2-}$

Cl ------------ 7 ----------------------- 1 ------------------------ none ---------------- $Cl^{-}$

K -------------- 1 ----------------------- none ----------------------- 1 ------------------ $K^{+}$

Mg ------------ 2 ---------------------- none ---------------------- 2 ---------------- $Mg^{2+}$

Be ------------- 2 ---------------------- none ---------------------- 2 ---------------- $Be^{2+}$

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8 0

2 years ago

Which type of weathering occurs most frequently at high elevations, and can bring mountains down to sea level over time?

gladu [14]

I pretty sure it’s rainfall

4 0

2 years ago

True or false: Observing a physical property of a substance will change the substances' identity. I NEED IT NOWWWWW

ale4655 [162]

False

only observing chemical property will change its identity

5 0

2 years ago

The sun is a mid-sized, main sequence star. What stage is next in the life cycle of the sun?

ss7ja [257]

Answer:

It starts to become a red giant!

Explanation:

7 0

3 years ago