Acids, Bases, and Natural Indicators

Try these questions

5 questions from this lesson’s quiz. Start the lesson to answer them and see the right answers.

1. 1. Which colour change shows that a solution is alkaline when phenolphthalein indicator is added?

   • A. Colourless to bright pink
   • B. Yellow to red
   • C. Blue to red
   • D. Purple to pink

2. 2. A learner extracts red cabbage indicator and adds it to filtered wood ash solution. What colour is most likely to be seen?

   • A. Pink
   • B. Green
   • C. Red
   • D. Purple

3. 3. Why can passing a mixture of water and lemon juice through sand NOT show whether the liquid is acidic?

   • A. Sand changes lemon juice into a base
   • B. Lemon juice is dissolved, so sand cannot remove it and a chemical test is needed
   • C. Sand removes all the colour from the water
   • D. Lemon juice is a suspended solid that blocks the sand

4. 4. A pupil spills concentrated acid while diluting it in the laboratory. Which safe rule should have been followed when diluting?

   • A. Add water quickly to the acid
   • B. Pour both liquids in together at the same time
   • C. Add the acid slowly to the water
   • D. Heat the acid before adding water

5. 5. What name is given to a reaction in which an acid and a base cancel each other to form a salt and water?

   Type your answer in the lesson.

More in Introduction to Integrated Science

• ▸Optical Instruments and Volumetric Glassware
• ▸Classification of Mixtures and Purity Determination
• ▸Physical Separation Techniques for Mixtures
• ▸Community Service Learning Water Purification Project
• ▸Acids, Bases and the pH Scale
• ▸Introduction to Laboratory Safety and Rules
• ▸Laboratory Design, Layout, and Safety Installations
• ▸Chemical Hazard Symbols

See every Grade 7 Integrated Science lesson →