posted by Taylor on .
Please help me....are these questions right or no? If not can you help me...any suggestions please?
7.(14). Which of the following is a salt?
I put down C- CaSO4, is that right or am I way off track?
8.(15). Which of the following is a strong electrolyte?
I believe this one is A- AgNO3, is that right?
9.(16). If a soluble ionic salt is added to water, which of the following best describes what occurs?
a. the salt first dissociates and then dissolves
b. the salt first dissolves and then dissociates
c. the salt will only dissolve if the solution is at a temperature above 100°C
d. the salt will not dissolve
e. the salt will form a precipitate
I have B- the salt first dissolves and then dissociates, is that correct?
10.(17). Which of the following salts is insoluble?
I have E- CaSO4, is that right?
11.(19). A buffer keeps a solution’s pH constant by
a. providing neutralizing ions
b. increasing the concentration
c. changing the H30+ concentration
d. releasing or absorbing H+ ions
e. lowering the pH
I have A- providing neutralizing ions
12.(22). Which of the following is a soluble salt?
I believe this one is C- but I am not positive, any suggestions?
13.(24). How many ions will one formula unit of CaCl2 produce?
I have D- 3, that’s right, right?
Thanks for the help in advance!
I think 9 is correct but technically, I think both dissolving and dissociation occur together. The ions are already there in the crystal. In dissolving, the water dipoles pull the ions apart which tears up the crystal bonds (structure) which leaves the ions to be hydrated. So, technically, I think the ions are already there when they get pulled apart from the crystal.
11 is not correct. I think a better choice is d.
The others look ok to me.