Question

2. The alkalinity of a fluid (pH) can be modeled in terms of its hydrogen ion concentration (H+, measured in moles/liter) of the fluid using the model shown below:pH = - log(H^+)A lab technician finds that a sample of fluid has a pH of 4.5. What is the hydrogen ion concentration of the fluid?

Answer 1

Given the equation:

`pH=-log\mleft(H^+\mright)`

You know that a lab technician finds that a sample of fluid has this pH:

`pH=4.5`

Then, in order to find the hydrogen ion concentration of the fluid, you need to follow these steps:

1. Substitute the pH given in the exercise into the equation:

`4.5=-log(H^+)`

Multiply both sides by -1:

`-4.5=\log (H^+)`

2. Solve for:

`H^+`

Remember that, by definition:

`\log _b\mleft(c\mright)=a\Rightarrow b^a=c`

In this case, you can identify that:

`\begin{gathered} a=-4.5 \\ b=10 \\ c=H^+ \end{gathered}`

Hence, substituting values and simplifying, you get:

`\begin{gathered} b^a=c \\ 10^(-4.5)=H^+ \\ H^+=0.00003162278\text{ }(moles)/(liter) \end{gathered}`

Therefore, the answer is:

`H^+=0.00003162278\text{ }(moles)/(liter)`