After looking at the table I believe the answer is 5. phenolphthalein, color change at pH 8-10. Phenolphthalein is an organic compound used as an acid-base indicator. It is colorless in acid solutions and turns pink to red as the solution becomes alkaline. The compound is also medically used as a cathartic.
What do you need to convert them to? Moles to mass?
A hypothesis is how you think the experiment is going to end
Answer: m = 17.5 g Cl
Explanation: To find the mass of Cl we will need to convert the moles of Cl to mass using the relationship of 1 mole = molar mass of Cl.
0.500 mole Cl x 35 g Cl / 1 mole Cl
= 17. 5 g Cl