Question 211020
Find the pH of an acidic substance of your choice. Using this pH, show how to find the hydrogen ion concentration, [H+], of the substance using the formula. Discuss the meaning of pH and [H+], the pH scale and why your chosen substance is acidic. Use scientific notation or enough decimal places so that your answer has at least 3 place values. For example, either use 3.44*10-6 or 0.00000344. 
I picked Baking soda. Baking soda is NaHCO3. 
The formula is:
pH = -log10 [H+] 
Baking soda has a pH of 9. It is a base, since the pH is above 7. 
You first plug 9 into the formula: 
9 = -log10 [H+] 
Then divide by -1: 
-9 = log10 [H+] 
Take 10 on each side: 
10^-9 = 10log10 [H+] 
Simplify: 
10^-9 = [H+] 
[H+] = 10^-9 mol/L 
[H+} = 0.000000001 mol/L
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Comment: 
Your work looks good to me.
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Cheers,
Stan H.