It's A, t<span>The figure is a molecule and an element.</span>
Answer:
b. mercury
Explanation:
Fishes and some other sea foods are are known to concentrate mercury in their bodies. Consumption of these products gradually accumulate mercury in the body over time.
More specifically, fishes like swordfish, king mackerel and shark are known to concentrate higher amount of mercury than other species of fishes. Hence, limiting their consumption will protect humans from mercury poisoning.
The correct option is b.
The statement that is true is that B. Atoms always remain intact during chemical reactions.
Atoms simply mean the <u>basic units of matter.</u> They're the defining structure of an element. Atom is also known as the smallest unit of matter.
It should be noted that atoms always remain intact during chemical reactions. They cannot be added and removed when there are <em>chemical reactions.</em>
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brainly.com/question/19338615
Answer:
all the elements in the same period have the same valence electrons.
Answer:
Balanced Chemical equation:
4Na + O₂ → 2Na₂O
Explanation:
Chemical equation:
Na + O₂ → Na₂O
Balanced Chemical equation:
4Na + O₂ → 2Na₂O
Four mole of sodium combine with one mole of oxygen and form two mole of sodium oxide.
Coefficient with reactant and products:
Na 4
O₂ 1
Na₂O 2
Oxygen is present in group sixteen and have six valance electrons. while sodium is alkali metal and present in group one and have one valance electron.
Oxygen needs two electron to complete the octet while sodium need to lose the one electron to get the complete octet.
When oxygen is combine with sodium it gain its two valance electrons from two sodium atom and form anion while sodium loses its valance electron to wards oxygen and form cation. The bond form between them is ionic because one is metal and other is non metal and electrons are completely transfer from two sodium atom to one oxygen atom.
