A 7.00 mL sample of blood serum has a pH of 7.38
a. What is the concentration of H3O+?
b. What is the concentration of OH-?
c. How many moles of H3O+ are present?
I have no clue what to do and I don't have a calculator with me someone help me I would really appreciate it.
pH = -log(H3O^+) = 7.38
(H3O^+) = 4.16E-8
b. (H3O^+)(OH^-) = 1E-14
c. mols = M x L = ?
To solve this problem, you can use the formula for pH:
pH = -log[H3O+]
Given that the pH of the blood serum is 7.38, you can determine the concentration of H3O+ by rearranging the formula:
[H3O+] = 10^(-pH)
Now let's solve this step-by-step:
a. What is the concentration of H3O+?
To find the concentration of H3O+, substitute the given pH value into the formula:
[H3O+] = 10^(-7.38)
As you mentioned that you don't have a calculator, you can use an approximation.
10^-7 = 0.0000001
So, the concentration of H3O+ in the blood serum is approximately 0.0000001 M.
b. What is the concentration of OH-?
In pure water, the concentration of H3O+ and OH- are equal. However, in an acidic solution like blood serum (pH < 7), the concentration of H3O+ is greater than OH-.
Since we know the concentration of H3O+ is approximately 0.0000001 M, we can infer that the concentration of OH- is less than 0.0000001 M.
c. How many moles of H3O+ are present?
To calculate the moles of H3O+, you need to multiply the concentration by the volume of the blood serum sample. The volume of the blood serum sample is given as 7.00 mL, which is equivalent to 0.007 L.
Moles of H3O+ = [H3O+] * Volume
Moles of H3O+ = 0.0000001 mol/L * 0.007 L
Moles of H3O+ = 7.00 x 10^-10 moles
Therefore, there are approximately 7.00 x 10^-10 moles of H3O+ in the given blood serum sample.
No problem! I can help you with that. To find the answers to these questions, you will need to use the equation for pH:
pH = -log[H3O+]
Before we can calculate the concentration of H3O+ and OH-, we need to know the concentration of H3O+.
To determine the concentration of H3O+, we can use the equation:
[H3O+] = 10^(-pH)
a. To find the concentration of H3O+, substitute the pH value (7.38) into the equation:
[H3O+] = 10^(-7.38)
You can use the exponent function on your calculator, if you have one, or use the logarithm table to calculate this value. If you don't have a calculator with you, you can use online calculators or the calculator function on your smartphone.
b. The concentration of OH- in water can be calculated using the equation:
[OH-] = 10^(-14)/[H3O+]
Now that you know the concentration of H3O+ from part a, you can substitute it into the equation to find [OH-].
c. To calculate the number of moles of H3O+ present in the 7.00 mL sample, you need to use the equation:
moles = concentration x volume
Given the concentration you calculated in part a and the volume of the sample (7.00 mL), you can find the number of moles.
Remember to always pay attention to units and make any necessary conversions (e.g., from mL to L) to ensure consistent units throughout your calculation.
I hope this explanation helps you solve the problem! Let me know if you have any further questions.