HELP ME PLEASE im in a middle of a science quiz

Water (2510 g ) is heated until it just begins to boil. if the water absorbs 5.09×105 j of heat in the process, what was the initial temperature of the water?

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.

Phosphorous acid, h3po3(aq) , is a diprotic oxyacid that is an important compound in industry and agriculture. p k a1 p k a2 1.30 6.70 calculate the ph for each of the points in the titration of 50.0 ml of 1.5 m h3po3(aq) 1.5 m h 3 po 3 ( aq ) with 1.5 m koh(aq). 1.5 m koh ( aq ) .