Hydroxide ion is a strong and would react with H+ to form water
OH-+H+---->H2O
Answer: (3) silicon
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Silicon (Si)
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: ethane 
, propanone 
and water 
Boyle's law
I hope this helps
Hello!
The chemical reaction for the dissolving of calcium fluoride is the following:
CaF₂(s) ⇄ Ca⁺²(aq) + 2F⁻(aq)
In this reaction, and according to Le Chatelier's principle, the action that would shift this reaction away from solid calcium fluoride and towards the dissolved ions is the removing of fluoride ions.
Le Chatelier's principle states that in an equilibrium reaction, the system would shift in the opposite direction of the changes. If we remove fluoride ions from the system, it will shift towards the formation of more fluoride ions by dissolving more Calcium Fluoride to achieve equilibrium again.
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