Solubility Question

[T Time]

Hey guys
i ran across a G-Chem solubility question that has me confused. So if anyone can explain this to me it would be greatly appreciated:
"Which of the following gives a complete list of water soluble compounds" was the question and i had narrowed it down to these two choices which both seemed correct, however only b was marked as the right answer.
(b) NaOH; BaO; SrO
(c) Ba(OH)2; CsOH; MgSO4

i thought the rules stated that all hydroxides and oxides were insoluble except with Ca, Sr, Ba and the alkali metals, and that all sulfates were soluble except with Ca, Sr, or Ba. Can anyone please explain to me why c would be wrong since Ba is the exception for hydroxides, Cs is an alkali metal, and the sulfate is soluble since it is with Mg not Ca, Sr, or Ba. Thanks for any help! 😕

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[T Time]

anyone?......help?......please 😀

 

[doc toothache]

Hey guys
i ran across a G-Chem solubility question that has me confused. So if anyone can explain this to me it would be greatly appreciated:
"Which of the following gives a complete list of water soluble compounds" was the question and i had narrowed it down to these two choices which both seemed correct, however only b was marked as the right answer.
(b) NaOH; BaO; SrO
(c) Ba(OH)2; CsOH; MgSO4

i thought the rules stated that all hydroxides and oxides were insoluble except with Ca, Sr, Ba and the alkali metals, and that all sulfates were soluble except with Ca, Sr, or Ba. Can anyone please explain to me why c would be wrong since Ba is the exception for hydroxides, Cs is an alkali metal, and the sulfate is soluble since it is with Mg not Ca, Sr, or Ba. Thanks for any help! 😕

You may want to check the question as well as the answers. Group (c) compounds have greater solubility in water than group (b). NaOH is the exception to group (b).

 

[JBarr29]

give all four choices because i dont think either of those would be the answer to tell you the truth.

 

[T Time]

give all four choices because i dont think either of those would be the answer to tell you the truth.

Ok, here’s the full question and list of answer choices. This is question number 5 in the Kaplan Properties of Solutions Quiz.

Which of the following gives a complete list of water soluble compounds?
(a). .Al(OH)3 ; HCl ; NaOH
(b). .NaOH ; BaO ; SrO
(c). .Ba(OH)2 ; CsOH ; Mg(SO4)
(d). .KOH; KCl; Ba(SO4)

Right off the bat, I eliminated A and D since they both violate the solubility rules. However, B and C both seem correct to me. Only B was given credit as the correct answer for this. Could this be a mistake? Thanks!

 

[heatwheat]

Ok, here's the full question and list of answer choices. This is question number 5 in the Kaplan Properties of Solutions Quiz.

Which of the following gives a complete list of water soluble compounds?
(a). .Al(OH)3 ; HCl ; NaOH
(b). .NaOH ; BaO ; SrO
(c). .Ba(OH)2 ; CsOH ; Mg(SO4)
(d). .KOH; KCl; Ba(SO4)

Right off the bat, I eliminated A and D since they both violate the solubility rules. However, B and C both seem correct to me. Only B was given credit as the correct answer for this. Could this be a mistake? Thanks!

The answer is C. Hydroxides usually are insoluble, EXCEPT with Ba(OH)2. Also ALL alkali metal cations which would include CsOH. And SO4 is soluble EXCEPT with Ca2+, Sr2+, Ba2+, and Pb2+. So Mg(SO4) is soluble.

 

[Doa110]

The answer is C. Hydroxides usually are insoluble, EXCEPT with Ba(OH)2. Also ALL alkali metal cations which would include CsOH. And SO4 is soluble EXCEPT with Ca2+, Sr2+, Ba2+, and Pb2+. So Mg(SO4) is soluble.

But "B"could be the answer for the same reasoning. Group I is soluble...>NaoH
Hydroxides and oxides are insoluble Except with, GroupI, NH4, Ba, Sr, and TI.
So NaOH, BaO, and SrO are all soluble as well! May be the answer choices are not proper?

 

[klutzy1987]

Magnesium is not soluble. Only group one and CaBS are soluble. Sulfate is not part of the solubility rules, only Nitrates are always soluble, sulfates, it depends on what it is attached to.