Question:Why did I get these wrong?!?! Please correct it. Write equations for the dissociation of the following in water. Include physical states for all species. 1)CaCl2 CaCl2(s) --> Ca2+(aq) + Cl-(aq) 2) (NH4)2SO4 (NH4)2SO4(aq) ---> 2NH4+(aq)+SO4-(aq) 3) NaC2H3O2 NaC2H3O2(aq) ---> Na+(aq) + C2H3O2-(aq) >_< Help

Answers:I can see why you got all these wrong. The correct expressions would be 1) CaCl2 Ca2+ + 2Cl- Since there are 2 Cl atoms in CaCl2, therefore, dissociation of CaCl2 in water will produce 2 Cl- (chloride ions) in solution, which you haven't considered. 2) NH4)2SO4 2NH4+ + SO4 2- The valency of sullphate (SO4 2-) anion is 2 and not 1. 3) N2C2H3O2 is sodium acetate, and can be written as CH3COONa. CH3COONa Na+ + CH3COO- This one was correct.

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Question:also what is the dissociation of each of these compounds in water? hydrochloric acid sulphuric acid (assume only one hydrogen is ionised) magnesium hydroxide phosphuric acid (write an equation for the three ionised hydrogens) THANKS! =D

Answers:NaOH = Na+ + OH- HCl + H2O = H3O+ + Cl H2SO4 + H2O = H3O+ + HSO4- Mg(OH)2 = Mg2+ + 2 OH- H3PO4 + H2O = H3O+ + H2PO4- H2PO4- + H2O = H3O+ + HPO42- HPO42- + H2O = H3O+ + PO43-

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Question:Is it H2SO4 2H+ + SO4-?

Answers:H2SO4 + H2O >> HSO4- + H3O+ HSO4- + H2O >> SO42- + H3O+ H2SO4 + 2 H2O >> SO42- + 2 H3O+

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Question:can anyone write an example? thanks!

Answers:using hydrochloric acid as an e.g. HCl (aq) ---> H+(aq) + Cl- (aq) the H+ are fully dissociated into the solution suggesting it's a strong acid.

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