Answer with clear explanation -

Determine the dilution factor (DF) used in a dilution using the data below. Express your answer as a ratio to 1 significant figure. Write your answer in the space below;

C₁ = 1000 mg/L

V₁ = 10 mL

C₂ = 100 mg/L

V₂ = 100 mL

Express 5 grams of substance dissolved in 100 mL of water as a percentage (include appropriate unit).

During the preparation of a solution of diluted ethanol, 20 mL of ethanol was added to a 100 mL volumetric flask and made to volume. Calculate the percentage of ethanol in the flask. Express your answer as a whole number.

What size volumetric flask was used in the preparation of a 25% ethanol solution if 50 mL of ethanol was transferred and the flask made up to volume with water?

What volume of ethanol was used in making 0.5 L of a 15% ethanol solution?

Calculate the percentage of salt if 5 g of salt is dissolved into a 250 mL volumetric flask. Express to 1 significant figure with appropriate unit.

Solution preparation

To analyse nitrate ions (NO₃^-) in a solution, special solutions of a known nitrate concentration (termed standard solutions) need to be prepared. In this scenario, you have been provided with the following data about a standard solution:

Volume = 500 mL

Concentration = 1 g/L NaNO₃

Formula weight NaNO₃ = 85 amu

Use your skills and knowledge to perform the calculations requested below.

1. Calculate the mass of the salt used to make up the solution. Express your answer to 2 significant figures.

2. Calculate how many moles of NaNO₃ the mass is equivalent to. Express your answer to 2 significant figures.

3. Calculate the molarity of the solution. Express your answer to 2 significant figures.

4. Express the concentration as %w/v to 2 significant figures.