10 cm³ of 0.4 M sodium hydroxide are added to 40 cm³ of 0.2 M hydrochloric acid. The resulting mixture will be

1. Neutral
2. Alkaline
3. Dilute
4. Acidic
5. Amphoteric

The mass of sodium hydroxide contained in 25 cm³ of 0.1 M NaOH is

1.  0.5 gm
2. B 2.85 gm
3.  250 gm
4.  0.2 gm
5.  25 gm

How many moles of oxygen are required for the complete combustion of 2.2 g of C3H 8 to form carbon dioxide and water?

1. 0.050 moles
2. 0.15 moles
3. 0.25 moles
4. 0.50 moles
5. 0.025 moles.

Which of the following solutions is the most concentrated?

1. 50 g of calcium carbonate in 100 cm³ of water
2. 60 g of sodium chloride in 200 cm³ of water
3. 65 g of potassium nitrate in 100 cm³ of water
4. 120 g of potassium sulphate in 200 cm³ of water
5. 50 g of sodium hydroxide in 200 cm³ of water.

   In the titration of a monoprotic acid with a solution of sodium hydroxide of known concentration, what quantities will be equal at the equivalence point?

1. concentration of hydroxide solution and hydronium ions.
2. number of moles of hydroxide ions added and number of moles of hydronium ion initially present.
3. number of moles of hydroxide solution added and volume of acid solution initially present.
4. number of moles of hydroxide ion added and the number of moles of monoprotic acid initially present.
5. volume of sodium hydroxide solution added and volume of acid solution initially present.

1.4 g of potassium hydroxide is dissolved in water to form 250 cm³ of solution. What is the molarity of this solution?

1.  0.01 M
2.  0.1 M
3.  1.4 M
4.  5.6 M
5.  6.0 M

(b) 25 cm of a molar solution of sodium hydroxide is diluted to 85 cm . Calculate the concentration of the solution after dilution. (Give your answer in two decimal places). (7 marks)

8.(a) Calculate the concentration in g /dm³ of vinegar (CH₃COOH) if 25.0 cm³ of 0.1 M sodium hydroxide reacts with 12.5 cm of vinegar.

(b)By giving a reason, suggest the suitable indicator for the reaction in 8(a) above. (7 marks)

Read the following information carefully then answer questions that follow: 25 cm³ of potassium hydroxide were placed in a flask and a few drops of phenolphthalein indicator were added. Dilute hydrochloric acid was added until the indicator changed colour. It was found that 21 cm³ of acid were used.

(b) (i) What piece of apparatus should be used to measure out accurately 25 cm³ of sodium hydroxide solution?

(ii) What colour was the solution in the flask at the start of the titration?

(iii) What colour did it turn when the alkali had been neutralized? (3 marks)

(c) (i) Was the acid more concentrated or less concentrated than the alkali? Give reasons for your answer.

(ii) Name the salt formed in the neutralization.

(iii) Write an equation for the reaction. (4 marks)

(d) Utilizing the given information describe how you can obtain pure crystals of the salt. (3 marks)