Acids and Alkalis (Part 2)

A chemical that changes colour in the presence of acids and alkalis is called a(an) _________.

Which of the following indicators shows a colour change from colourless to pink?

• Red cabbage juice

• Universal

• Litmus

• phenolphthalein

What is the other reactant in the equation:

.............................. + hydrochloric acid -> potassium chloride + water

• calcium hydroxide

• sodium hydroxide

• potassium hydroxide

• lithium hydroxide

What is the other product in the reaction:

Lithium hydroxide + sulfuric acid --> ............................... + water

• calcium sulfate

• lithium chloride

• lithium nitrate

• lithium sulfate

Moza tested a substance with phenolphthalein indicator. The colour changed to pink. Choose the best conclusion.

• The pH of the substance is 4.

• The pH of the substance is 6.

• The pH of the substance is 7.

• The pH of the substance is 9.

George added a few drops of methyl orange indicator to a liquid. It turned red. What can he conclude?

• The substance is probably water with pH 7.

• The substance is probably bleach with pH 12.

• The substance is probably vinegar with pH 3.

• The substance is probably sodium hydroxide with pH 14.

Patricia knows she has an alkaline substance. She tested it using an indicator and the solution turned blue in colour. Which indicator did she use?

• litmus

• phenolphthalein

• methyl orange

Y7 Scientists used a pH meter to test the pH of some common substances. They recorded their results in the table shown. Which substance is most alkaline?

• blood

• coffee

• Clorox

• Coke

Y7 Scientists used a pH meter to test the pH of some common substances. They recorded their results in the table shown. Why do you think Coke/Pepsi is not good for health?

• Because they are alkaline and will dissolve the calcium minerals in our teeth.

• Because they are acidic and will dissolve the calcium minerals in our teeth.

• Because they are neutral and will dissolve the calcium minerals in our teeth.

Look at the results table. What can you conclude about blood?

• Blood is neutral.

• Blood is highly alkaline.

• Blood is slightly acidic.

• Blood is slightly alkaline.