[katrina007]

Hello,

I needed some help with my Chemistry Homework. I have 4 questions that I'm not so sure of the answer. I've given my best try. Please if someone can help me correct my answers or tell me which one is the right one and how to determine/solve it... Thanks in advance.


Question One:
Which gas is expected to be more soluble in H2O?

a) O2
b) Cl2
c) HF
d) H2
e) HCl

** I think that Oxygen gas is more soluble in H2O.

Question Two:
Which produces the greatest number of Ions when one mole dissolves in water?

a) NaCl
b) NH4NO3
c) NH4Cl
d) Na2SO4
e) Sucrose

** I think its (e) Sucrose. I tried converting the molar mass which (e) has the highest (342.29g/mol) to # of Ions (6.022x10^23)

Question Three:
A 1.34m (Molality) aqueous solution of compound X had a boiling point of 101.4 degrees Celcuis. Which one of the following could be compound X? The boiling point elevation constant Kbp for water is 0.52 degrees Celcuis/m (Molality).

a) CH3CH2OH
b) C6H12O6
c) Na3PO4
d) KCl
e) CaCl2

** I have no clue how to do this one. I tried using the Boiling Point of Elevation equation (delta)(T) = Kbp x m but I don't know what to do afterwards. Please explain this one.

Question Four:
The activation energy of a reaction is 76.7KJ/mol. How many times faster will the reaction occur at 50 degrees Celcuis that at Zero (0) degrees Celcuis (assume equal initial concentrations).

a) 50
b) 70
c) 120
d) 190
e) 360

** Dont know how to approach this question either. Please explain.


Any help will be appreciated.
Regards,
Katrina
gettrinatak007@yahoo.com

[Borek]

Which gas is expected to be more soluble in H2O?

a) O2
b) Cl2
c) HF
d) H2
e) HCl

** I think that Oxygen gas is more soluble in H2O.

Dissociation increases solubility.

Which produces the greatest number of Ions when one mole dissolves in water?

a) NaCl
b) NH4NO3
c) NH4Cl
d) Na2SO4
e) Sucrose

Write dissociation reactions.

A 1.34m (Molality) aqueous solution of compound X had a boiling point of 101.4 degrees Celcuis. Which one of the following could be compound X? The boiling point elevation constant Kbp for water is 0.52 degrees Celcuis/m (Molality).

a) CH3CH2OH
b) C6H12O6
c) Na3PO4
d) KCl
e) CaCl2

** I have no clue how to do this one. I tried using the Boiling Point of Elevation equation (delta)(T) = Kbp x m but I don't know what to do afterwards. Please explain this one.

Equation (as listed) lacks the most crucial coefficient for this question - Van 't Hoff factor.

The activation energy of a reaction is 76.7KJ/mol. How many times faster will the reaction occur at 50 degrees Celcuis that at Zero (0) degrees Celcuis (assume equal initial concentrations).

a) 50
b) 70
c) 120
d) 190
e) 360

** Dont know how to approach this question either. Please explain.

Arrhenius equation.

[thuanh]

"dissociation increases solubility"? This is my friend's idea:
CaCO3 dissociates completely but it doesn't disolve well,CH3COOH dissociates not so much but it disolves limitlessly.