Hello,
To use the log function press [LOG] enter the number, close the right parenthesis and press [ENTER]
[LOG] 1 [ ) ] [ENTER] gives 0.
I have a hunch your problem is not the syntax of the log function on this calculator, but the calculation of the pH from the concentration or the calculation of a concentration from the pH. So I am inserting a copy of a previous post on the question. Use it as an exemple.
Let y=10^(x) 10 to the power of x
Take the log of both tems of the equality. You get log(y)=log[10^(x)] where I used square brackets for clarity. But from the general properties of logarithms
log(b^(a)) = a*log(b)
Applied to our expression above log(10^x)=x*log10
But since we are using log as log in base 10, log_10(10)=1 so log(y)=x
We thus have two equivalent relations
y=10^x <----> x=log(y) The double arrow stands for equivalence.
If y is the log of x, then x is the antilog of y
Your question: With log_10 standing for logarithm in base 10
pH=-log_10(c) where c= concentration. Then log_10(c)=-pH
The equivalence above translates as
log_10(c)=-pH is equivalent to c=10^(-pH)
The concentartion corresponding to a pH of 7.41 is
c=10^(-7.41)=3.89x10^(-8)
Hope it helps
The way to use the log button right is described in the first line of the post. Press the button. Enter the number. Close the right parenthesis. Press enter. That is all!. That aswers your question completely.
The rest of the post was added for the benefit of the students who struggle with pH calculations. And there are a lot of them out there.
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