PLS HELP! WILL GIVE BRAINLIEST! Which of the following could you use to test the pH of a soil?

lime
calcium hydroxide
hydrochloric acid
universal indicator

Which produce would best increase the amount of heat energy that is actually gained by calorimeter b

Which diagram shows the correct way to represent an ionic compound of magnesium oxide?

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.