Evaluate the next few problems with your calculator, using the "change of base" formula.
There is an example to the right.
1 point
1
Question 20
20.
Use the change of base formula to evaluate. Round to the hundredths place (2 decimal places).
1 point
1
Question 21
21.
Use the change of base formula to evaluate. Round to the hundredths place (2 decimal places).
1 point
1
Question 22
22.
Use the change of base formula to evaluate. Round to the hundredths place (2 decimal places).
1 point
1
Question 23
23.
Use the change of base formula to evaluate. Round to the hundredths place (2 decimal places).
1 point
1
Question 24
24.
The acidity level, pH, of a liquid is given by the formula:
where h+ is the concentration of hydrogen ions in the water, measured in moles per liter.
Elijah decides to have a pool party for his birthday party. Before the party, the pool had a pH level of 4.8. After everyone went swimming, they measured the pool, and it had a concentration of h+ ions of .00000042 moles per liter.
Find the pH level of the pool AFTER the party and determine how much higher the pH level is now than before the party.
