Find the hydroxide ion concentration [OH-] of an HCl solution with a pH of 2.75. [OH-]=
M (Use 2 decimal places)

Compare and contrast physical changes with chemical changes.

3. how much energy in joules is required to evaporate .0005 kg of liquid ammonia to vapor at the same temperature? 4. how much energy ( in megajoules ) is given up by .75 kg of water at 0c when it freezes to form ice at 0c? 5. explain how heat works between and at critical temperatures?

Light waves travel than sound waves.