5. a. How many mol of sodium chloride, NaCl, are required to prepare 0.2 L of a 3 M solution? b. How many grams is this (hint: molar mass of NaCl =
U?

a. 0.6 moles

b. 35.1 grams

Given

Volume = 0.2 L

Molarity = 3 M

Required

mol of Sodium chloride

Solution

Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

Where

M = Molarity

n = Number of moles of solute

V = Volume of solution

Input the value :

n = M x V

n = 3 M x 0.2 L

n = 0.6 moles

Mass of NaCl :

= mol x molar mass of NaCl

= 0.6 x 58.5 g/mol

= 35.1 grams

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.