When humans burn fuel/cut down tress, they will increase the level of carbon dioxide within the atmosphere. Tress "inhale" the carbon dioxide within the atmosphere and without them, the excess will still linger. Carbon dioxide is a byproduct of burning fuel thus, it will increase the levels in the atmosphere.
Collagen in the human body connects and supports bodily tissue such as skin, bones, muscles and cartilage. It supports the internal organs and can even be found in teeth! Collagen's main function is to sustain tendons, skin, and cartilage and provide firmness and elasticity to those structures.
Nitrogen can form a diatomic molecule held together by triple bonds.
The metals will lose electrons while the non metals will gain electrons in order to attain octet structure.
An ion can be cation (positively charged) or anion (negatively charged).
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;
<u>Element</u>--<u>valence electron</u>--<u>electrons to gain</u>--<u>electrons to lose</u>--<u>ion formed</u>
O ------------ 6 ---------------------- 2 ------------------------ none -------------- 
Ca -------- 2 ----------------------- none ---------------------- 2 ------------------ 
Br ----------- 7 --------------------- 1 ------------------------ none --------------- 
S ------------ 6 ----------------------- 2 ------------------------ none --------------- 
Cl ------------ 7 ----------------------- 1 ------------------------ none ----------------
K -------------- 1 ----------------------- none ----------------------- 1 ------------------ 
Mg ------------ 2 ---------------------- none ---------------------- 2 ---------------- 
Be ------------- 2 ---------------------- none ---------------------- 2 ---------------- 
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