16. Ned observed an unknown chemical (A) reacting with hydrochloric acid (HCI). The reaction formed potassium chloride salt (KCl) and another unknown substance (B). Ned wrote down what he knew about
the reaction:
A + HCl → KCl + B
From this information, Ned inferred that unknown substance A was potassium (K) and that unknown
substance B was hydrogen (H2). What is another logical interpretation of this data?
a. A is chlorine (Cl) and B is hydrochloric acid (HCI).
b. A is potassium chloride (KCl) and B is hydrochloric acid (HCI).
c. A is potassium hydroxide (KOH) and B is hydrogen gas (H2).
d. None of the above.

Part b: study of equilibrium on solubility: mg(oh)2(s) ⇌ mg2+(aq) + 2 oh–(aq) cloudy clear (pink) 7. a. b. 8. a. b. 9. 10. 11. 12. when adding concentrated hydrochloric acid, how did the appearance of the equilibrium mixture change? the change in appearance indicated a shift in the point of equilibrium. in which direction did the equilibrium shift? (l) left (r) right explain your answer to question 7a. you should indicate which ion was added to or removed from the equilibrium mixture. when adding edta, how did the appearance of the equilibrium mixture change? the change in appearance indicated a shift in the point of equilibrium. in which direction did the equilibrium shift? (l) left (r) right explain your answer to question 8a. you should indicate which ion was added to or removed from the equilibrium mixture. upon heating in which direction is the equilibrium shifting? upon cooling in which direction is the equilibrium shifting? is the forward reaction a. endothermic explain your answers to questions 9, 10, and 11. (l) left (r) right (l) left (r) right b. exothermic

The fact that the total amount of energy in a system remains constant is a(n)

What are the similarities between compounds and mixtures?