Finding major species in aqueous solutions

[parwana]

Which of the following are correct statements ?


a) In an aqueous solution of NH4Cl, H2O, NH4+ and Cl-are the major species present

b) In an aqueous solution of NaCH3CO2, H2O, Na+ and HCH3CO2 are the major species present

c) In an aqueous solution of HCN, H2O, H3O+ and CN- are the major species present

d) In an aqueous solution of HNO3, H2O, H3O+ and NO3- are the major species present

e) In a solution of CH3CO2H and NaOH, Na+ is a spectator ion

I know a should be right since those are ions, but don't know about the rest. Help

 

[Borek]

Which of the following are correct statements ?

You should look at the Ka values for all species and decide, whether acids are dissociated or not. That's the main point.

Try BATE for these calculations - while you should be able to make them by yourself it can help check the results

 

[ravenprp]

A) This statement is correct. In an aqueous solution of NH4Cl, the major species present are H2O, NH4+, and Cl-. This is because NH4+ and Cl- are both ions that dissociate in water, while H2O is the solvent.

B) This statement is also correct. In an aqueous solution of NaCH3CO2, the major species present are H2O, Na+, and HCH3CO2. Similar to the previous solution, Na+ and HCH3CO2 are both ions that dissociate in water, while H2O is the solvent.

C) This statement is also correct. In an aqueous solution of HCN, the major species present are H2O, H3O+, and CN-. HCN is a weak acid that dissociates into H3O+ and CN- in water.

D) This statement is also correct. In an aqueous solution of HNO3, the major species present are H2O, H3O+, and NO3-. Similar to HCN, HNO3 is a strong acid that dissociates into H3O+ and NO3- in water.

E) This statement is incorrect. In a solution of CH3CO2H and NaOH, the major species present are H2O, CH3CO2H, and OH-. Na+ is not a major species, but rather a spectator ion. This means that it does not participate in the chemical reactions and remains in its ionic form.