I really need help on this

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12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer

What amount of heat is exchanged when 106.2 grams of substance y goes from a liquid at 35 degrees celsius to a solid at the same temperature? melting point of substance y = 35 degrees c; δhvaporization = 3.67 j/mol; δhfusion = 3.30 j/mol. mwsubstance y = 28.22 g/mol. −12.4 j −3.51 x 102 j 1.24 x 101 j 351 j

Which of the following molecules is polar? c3h7oh c2h5cooh