Can you tell if a liquid is a pure substance or a solution by looking at it? Explain why or why not.

No, you cannot tell by looking at it if something is a pure substance or a solution. In a solution, the different particles combine so thoroughly that it appears to contain only one kind of particle throughout, just like a pure substance.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

can you list the answers so i can answer