How many formula units make up 36.2 g of magnesium chloride (MgCl2)?

2.29 × 10²³ formula units of MgCl₂

Explanation:

Given data:

Mass of MgCl₂ = 36.2 g

Number of formula units = ?

Solution:

The given problem will be solved by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

18 g of water = 1 mole = 6.022 × 10²³ molecules of water  = 6.022 × 10²³ formula units of water.

In 36.2 g of MgCl₂:

Number of moles = mass / molar mass

Number of moles = 36.2 g / 95.211 g/mol

Number of moles = 0.38 mol

1 mole = 6.022 × 10²³ formula units

0.38 mol / 1mol × 6.022 × 10²³ formula units

2.29 × 10²³ formula units of MgCl₂

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

it's c. elements are placed in rows based on how may valencies electrons have.