Homework: Logarithms - Caleb Guesno | Library

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Logarithms help us deal with ___________________________________ 

The logarithm of a number is the

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What does the calculator button mean?

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What is log264=_______ 

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pH tells us how ____________________  a sample is.

What is the formula for finding pH

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Convert these two amounts to scientific notation:
A) .0000000398 = _______x 10 _______ 
B) .00000000398 = _______x 10 _______ 


Hint scientific notation:
.098  is 9.8 x 10-2

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Calculate the pH of these two amounts using the formula.
A) .0000000398, pH = _______
B) .00000000398, pH = _______ 

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Convert this number into scientific notation:
A) .00000765 =  _______ x 10 _______ 
Calculate the pH of this amount above using the formula
pH = - log10[H+]:
*if .00000765 is [H+]
B) pH = _______ 

The measure of acidity of a liquid is called the pH of the liquid. This is based on the amount of hydrogen ions (H+) in the liquid. The formula for pH is:

pH = −log[H+]

where [H+] is the concentration of hydrogen ions, given in a unit called mol/L (“moles per liter”).

Liquids with a low pH (down to 0) are more acidic and those with a high pH are more basic.

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If the pH of a sample is 3.5. Then what is the [H+] concentration? Use the formula.
pH = −log[H+]

[H+] = _______ 
What is the above answer in scientific notation?
_______ x 10 _______ 