KSSM Chemistry Chapter 6 Acids, Bases and Salts

Which of the following is true about ammonia solution in methylbenzene?

• Has pH value more than 7

• No change on red litmus paper

• Ionises partially to produce hydroxide ions

• Ammonium ions and hydroxide ions move freely in the solution

Several drops of nitric acid are added to a test tube that is filled with potassium chloride solution. What is the most suitable pH value for the mixture?

• 2.0

• 5.5

• 7.0

• 9.8

Phosphoric acid is a weak acid that

• has a pH value of 1.0

• cannot neutralise alkaline solution

• changes red litmus paper to blue

• ionises partially in water to produce hydrogen ions

Which chemical equation represents a neutralisation reaction?

• Mg + H₂SO₄ → MgSO₄ + H₂

• ZnCl₂ + 2HNO₃ → Zn(NO₃)₂ + 2HCl

• 2HCl + CaCO₃ → CaCl₂ + CO₂ + H₂O

• NaOH + CH₃COOH → CH₃COONa + H₂O

14.9 g of solid potassium chloride, KCl needs to be dissolved in distilled water to produce 0.4 mol dm^-3 potassium chloride solution, KCl. What is the volume of distilled water needed to dissolve the solid potassium chloride ?

[Molar mass of KCL = 74.5 g mol^-1]

• 50 cm³

• 200 cm³

• 500 cm³

• 2 000 cm³

50 cm³ of 0.4 mol dm^-3 sodium hydroxide solution, NaOH that is filled into a conical flask is titrated with 1.0 mol dm^-3 of sulphuric acid, H₂SO₄. Determine the final volume of solution in the conical flask.

• 10.0 cm³

• 60.0 cm³

• 70.0 cm³

• 100.0 cm³

The following figure shows the steps taken in a laboratory activity. What is the purpose of conducting that laboratory activity?

• To prepare soluble salt

• To prepare insoluble salt

• To purify salt that contains impurities

• To identify anions that present in the salt solution

Which salt is not decomposed when heated strongly?

• Zinc nitrate

• Ammonium chloride

• Potassium carbonate

• Copper(II) sulphate

A sample of salt X is a soluble ammonium chloride salt.

You are required to verify the cations and anions that are present in that salt sample. What is the pair of reagents needed to confirm the presence of cation and anion?

• Cation: Nessler reagent

  Anion: Nitric acid and silver nitrate solution

• Cation: Nessler reagent

  Anion: Nitric acid and barium nitrate solution

• Cation: Potassium hexacyanoferrate(III) solution

  Anion: Nitric acid and barium nitrate solution

• Cation: Potassium hexacyanoferrate(III) solution

  Anion: Nitric acid and silver nitrate solution

The flow chart shows an observation that is obtained from an anion test. Solution Y contains two anions. The anions are possibly

• sulphate ion and carbonate ion

• nitrate ion and carbonate ion

• sulphate ion and chloride ion

• nitrate ion and chloride ion