Acids and bases II

This task is about acids and bases.

The pH of a substance indicates whether it is acidic, basic, or neutral:

  • Acidic substances have a pH of less than 7.
  • Neutral substances have a pH of 7.
  • Basic substances have a pH greater than 7.

Using the table of pH values below, answer the following questions.

Substance pH
lemon juice 2
vinegar 3
milk 7
tap water 7
baking soda 9
milk of magnesia 11

Question 1Change answer

a)  i)  Wasps stings are basic.
         Name one substance from the table you would apply to a wasp sting to make it less painful.
     ii)  Why did you choose this substance?
 

Question 1Change answer

b)  A white substance is found on some nails in the garage. You scrape a little bit off and find its pH to be 8. 
     Name two substances from the table you could use to remove the white substance from the nails.
1. 
2. 

Question 1Change answer

c)  If the concentrations and volumes are equal, a basic substance will  an acidic substance when they are mixed together, and the new substance will have a pH of 7.