Round 1
1. What does the pH scale measure?
a) Temperature
b) How heavy something is
c) How acidic or alkaline a substance is
d) If a substance is a solid or liquid
c) How acidic or alkaline a substance is
1. Which number on the pH scale represents a strong acid?
a) 13
b) 10
c) 1
d) 7
c) 1
1. A solution turns blue with universal indicator. What type of solution is it?
a) Strong acid
b) Weak acid
c) Weak alkali
d) Strong alkali
c) Weak alkali
2. What is the pH of a neutral substance?
a) 0
b) 7
c) 14
d) 3
b) 7
2. What ion do alkalis produce in water?
a) H⁺
b) OH⁻
c) Cl⁻
d) Na⁺
b) OH⁻
2. If a solution has a pH of 2, what is it likely to contain?
a) Hydrogen ions (H⁺)
b) Water molecules
c) Hydroxide ions (OH⁻)
d) Sodium ions (Na⁺)
a) Hydrogen ions (H⁺)
3. Which colour does litmus paper turn in an acid?
a) Blue
b) Green
c) Red
d) Purple
c) Red
3. What colour does phenolphthalein turn in an alkali?
a) Colourless
b) Pink
c) Red
d) Yellow
b) Pink
3. Which of these would turn methyl orange yellow?
a) Lemon juice
b) Soap solution
c) Vinegar
d) Hydrochloric acid
b) Soap solution
4. What type of ion do acids produce in water?
a) OH⁻ ions
b) H⁺ ions
c) O²⁻ ions
d) Na⁺ ions
b) H⁺ ions
4. Methyl orange turns ______________ in acid.
a) Pink
b) Yellow
c) Orange
d) Red
d) Red
4. A student adds phenolphthalein to a solution and it stays colourless. What can you say about the solution?
a) It is strongly alkaline
b) It is weakly alkaline
c) It is neutral or acidic
d) It is boiling
c) It is neutral or acidic
5. Which of these is an indicator?
a) Methyl orange
b) Water
c) Vinegar
d) Salt
a) Methyl orange
5. Universal indicator shows green when a solution is:
a) Acidic
b) Neutral
c) Strongly alkaline
d) Very acidic
b) Neutral
5. Why do acids conduct electricity in water?
a) They contain metals
b) They form H⁺ ions that move and carry charge
c) They release oxygen
d) They turn red
b) They form H⁺ ions that move and carry charge