STRENGTH OF ACID AND ALKALI

What is the ions that responsible to show the acidic property of a substance?

• Hydroxide ion, OH^-

• Nitrate ion

• Hydrogen ion, H⁺

• Oxide ion, O ^2-

When hydrogen chloride gas is added into a beaker containing water, it will

• react with water and produce colorless solution

• Dissolve in water and produce H⁺ ions

• Ionise in water and produce H⁺ ions

• remain as molecules

What will happen to the bulb that connect to beaker containing ammonia gas that dissolve in propanone?

• Bulb lights up

• Bulb do not lights up

• Turns from red to blue

• Turn from blue to red

Which of the substance is a strong acid?

• NH₃

• NaOH

• CH₃COOH

• HNO₃

Which of the substance is a weak alkali?

• sodium hydroxide solution

• ammonia gas

• ammonia solution

• Potassium hydroxide solution

Which statement is correct about an acid?

• The higher the concentration of acid, the higher the pH value

• The lower the concentration of acid, the lower the pH value

• The higher the concentration of H⁺ ions, the lower the pH value

• The higher the concentration of H⁺ ions, the higher the pH value

Which statement is correct about an alkali

• Strong alkali has low pH value

• Strong alkali ionise partially in water

• Strong alkali has high concentration of H⁺ ions

• Strong alkali dissociate completely in water

Why pH value for ethanoic acid is higher than nitric acid with the same concentration ?

• ethanoic acid is more strong than nitric acid

• Ethanoic acid ionise completely in water

• Ethanoic acid ionise partially in water

• Ethanoic acid has high concentration of H⁺ ions than nitric acid

When ammonia gas is added into water, it will ionise and produce ion X.

Which statement is correct about ion X?

[choose more than 1 answer]

• Presence of ion X will turn red litmus paper to blue

• ion X is hydroxide ion

• Presence of ion X give the pH value between 8 to 14

• Presence of free moving ions X, made the bulb lights up.

Which statements are correct about acid and alkali

[You can choose more than 1 statement]

• Strong acid contain high concentration of hydrogen ions

• Strong alkali contain high concentration of hydroxide ions

• HCl is a strong alkali

• pH value for ammonia solution is 14