Answer: The correct formula is 
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here magnesium is having an oxidation state of +2 called as 
cation and bromine 
is an anion with oxidation state of -1. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral .
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic bond.
Answer:
elements have the same number of valence electrons and similar chemical properties.
Explanation:
they have the same number
Explanation:
Reaction rate is a measure of speed of a chemical reaction.
Usually, based on rates, reactions can be divided into two parts:
- Slow reactions which usually takes a long time.
- Fast reactions which takes place completely in seconds or microseconds.
Reaction rate can be defined as a change in the concentration of a reactant or product per unit time:
The unit is mol dm⁻³ s⁻¹
Reaction rate = 
The measurement of the reaction rate is based on the disappearance of a reactant or appearance of a product with increasing reaction time.
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Reaction rate brainly.com/question/9642960
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The fourth most abundant element in terms of mass is Carbon.
The first, second, and third most abundant element in terms of mass are Hydrogen, Helium, and Oxygen, respectively.
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