A1 mm solution of a substance has a ph of 3. what must be true of this substance?

To have a PH of 3, it means that the substance must be acidic since a PH of less than 7  less means that the tested substance is acidic. If the PH is greater than 7 then it will be  a base or the opposite of acidic. PH of a solution can be tested with litmus paper ie qualitatively to see if it is an acid or a base. Aof an example of a base is NaOH sodium hydroxide and of an acid is H2SO4 or sulfuric acid.

May be this question have some options to choose the right answer.

Nevertheless, I can tell you a real true about the nature of that substance.

Take into account that the pH reveals whether a solution iis acid, basic or neutral.

The scale of pH goes from 0 to 14.

You can use this table:

pH value          kind of substance

7 < pH < 14      basic

pH = 7              neutral

0 < pH < 7        acid

So, the pH of that substance reveals that it is an acid.

Which metal is less dense