Explain why the formula and the name for the combination of magnesium and nitrate iron is mg(no3)2? what do the numbers mean?

Explanation:

The formula Mg(NO₃)₂ is written as such using the combining powers of the atoms or group of atoms that constitutes the compound.

The combining powers correspond to the number of electrons usually lost or gained or shared by atoms of elements during chemical combination or the number of positive or negative charges carried by ions.

The elements and/or ions exchange directly their combining powers or their simplest whole number ratio during formation of chemical formulae of compounds.

The combining power is also called valency.

For the compound Mg(NO₃)₂, we have two ions combining together to form the compound.

Mg has a valency of 2+ and NO₃ is a radical(a group of atoms that behaves as a unit) with a valency of -1:

    Mg NO₃

Combining powers   2     1

Exchange of

Combining power   1   2

Formula of compound Mg(NO₃)₂

The name of the compound is Magnesium nitrate.

When the combining powers are exchanged, 2 goes to the nitrate ion and the 1 comes to the magnesium ion resulting in Mg(NO₃)₂

For some compounds, we reduce the powers to the simplest ratio first before exchange occurs. For example: CuO

  Cu   O

Combining

Power   2   2

Simplest

Ratio   1   1

Exchnage

Of combi-

ning power 1   1

Formula of compound CuO