Final answer:
LiOH is soluble because hydroxides of Group I elements are soluble. Na2CO3 is soluble as most carbonates are insoluble, except for those containing potassium, sodium, or ammonium. Cu(OH)2 is insoluble, as are hydroxide salts of most transition metals.
Step-by-step explanation:
To determine whether a compound is soluble or insoluble, we refer to solubility rules. Based on these rules:
- LiOH (Lithium hydroxide) is soluble in water because hydroxides of Group I elements are soluble.
- Na2CO3 (Sodium carbonate) is soluble in water as all carbonates are insoluble except those of potassium, sodium, and ammonium.
- Cu(OH)2 (Copper(II) hydroxide) is insoluble in water because hydroxide salts of transition metals are typically insoluble, with few exceptions such as the hydroxides of calcium, strontium, and barium which are slightly soluble.
Considering other compounds:
- Na2SO4 (Sodium sulfate) is soluble.
- AgCl (Silver chloride) is insoluble.
- Ba(NO3)2 (Barium nitrate) is soluble.
- PbI2 (Lead(II) iodide) is insoluble.
- Mg(NO3)2 (Magnesium nitrate) is soluble.
- BaSO4 (Barium sulfate) is insoluble.
- FeCl3 (Iron(III) chloride) is soluble.
- Pb(CH3COO)2 (Lead(II) acetate) is soluble.