[777888]

1)Calculate the % ionization of water (According to H2O<->H+ + OH-) at SATP.

I tried to calculate but I don't know how to calculate the % ionization...

1000g/x=18.02g/1mol
x=55.4939 mol H2O

[H2O]=55.4939mol/L

In pure water,
[H+]=1.0x10^-7mol/L
[OH-]=1.0x10^-7mol/L

...

2)Is H3PO3 a strong acid? If an acid is monoprotic or diprotic, what does it mean?

I hope someone can teach me! Thank you

[AWK]

%=100x[H+]/[H2O]
Monoprotic acid split of one proton during dissociation, diprotic - two protons.
H3PO3 is diprotic because it real stucture id (HO)2PHO (one hydrogen atoms forms bond to P not to O) and is a weak acid.

[777888]

%=100x[H+]/{H2O]
Monoprotic acid spilt of one proton during dissociation, diprotic - two protons.
H3PO3 is diprotic because it real stucture id (HO)2PHO (one hydrogen atoms forms bond to P not to O) and is a weak acid.

Thank you!

% ionization:
=[H+]/[H2O]100%
=(1.0x10^-7)/(55.4939)x100%
=1.8x10^-7


But the answer is 10^-5%

Is the answer wrong?

[777888]

3)What are two diagnostic tests that can distinguish a weak acid from a strong acid?

[litmus paper, pH meter, phenolphthalein, are they called diagnostic tests?]

[Demotivator]

%=100x[H+]/[H2O]  is incorrect if you put in any  value for [H2O] other than 1. For solids and solvents the value in equlibrium equations are always taken as unit activity.
Therefore % = 100x[H+] = 10^-5

[777888]

%=100x[H+]/[H2O]  is incorrect if you put in any  value for [H2O] other than 1. For solids and solvents the value in equlibrium equations are always taken as unit activity.
Therefore % = 100x[H+] = 10^-5

Thanks
I thought that for every 55.4939 mol of H2O, 1.0x10-7 mol of H+ is produced. Why do you omit H2O?

[777888]

4.According to the table of acid-base indicators, what is the colour of litmus in a solution with a pH of 8.2, and methyl orange in a solution with a pH of 3.9?
Table of Acid-Base indicators:
Name        Colour of HIn   pH range   Colour of In-
litmus               red           6.0-8.0      blue
methyl orange    red           3.1-4.4     yellow
I don't know how to use the table...what are the meanings of colour of HIn, pH range, and colour of In-? How can I predict the pH of the above problem?

5a)If alizarin yellow is added to a solution, and the colour of the solution turns red, what is the solution pH?
How can I predict the pH? Can someone teach me one? Thank you!

[AWK]

%=100x[H+]/[H2O]  is incorrect if you put in any  value for [H2O] other than 1. For solids and solvents the value in equlibrium equations are always taken as unit activity.
Therefore % = 100x[H+] = 10^-5

Here we are talking about simple stoichiometry, not on equilibrium.
For very diluted solutions concentration and activity are equal.

[777888]

3)What are two diagnostic tests that can distinguish a weak acid from a strong acid?

[litmus paper, pH meter, phenolphthalein, are they called diagnostic tests?]

And also, does a strong acid have a lower pH than a weak acid?

[777888]

Here we are talking about simple stoichiometry, not on equilibrium.
For very diluted solutions concentration and activity are equal.

So is my answer correct???
% ionization:
=[H+]/[H2O]100%
=(1.0x10-7)/(55.4939)x100%
=1.8x10-7%

Thanks~

[777888]

4.According to the table of acid-base indicators, what is the colour of litmus in a solution with a pH of 8.2, and methyl orange in a solution with a pH of 3.9?
Table of Acid-Base indicators:
Name        Colour of HIn   pH range   Colour of In-
litmus               red           6.0-8.0      blue
methyl orange    red           3.1-4.4     yellow
I don't know how to use the table...what are the meanings of colour of HIn, pH range, and colour of In-? How can I predict the pH of the above problem?

5a)If alizarin yellow is added to a solution, and the colour of the solution turns red, what is the solution pH?
How can I predict the pH? Can someone teach me one? Thank you!

Anyone knows how to predict the colour?

[777888]

4.According to the table of acid-base indicators, what is the colour of litmus in a solution with a pH of 8.2, and methyl orange in a solution with a pH of 3.9?
Table of Acid-Base indicators:
Name        Colour of HIn  pH range  Colour of In-
litmus              red          6.0-8.0      blue
methyl orange    red          3.1-4.4    yellow

......
For question 4, I think that limus in a solution with pH 8.2 is blue. How about methyl orange in a solution with pH 3.9? (not red, not yellow)

......

5a)If alizarin yellow is added to a solution, and the colour of the solution turns red, what is the solution pH?

......

How can I know the pH? There are many possibilities to make the indicator turns red, right?


PLEASE *delete me* I don't understand...

[kevins]

1. What is the 'middle' color of the red ~ yellow?

2. What is the pH range of alizarin yellow?  

[777888]

1. What is the 'middle' color of the red ~ yellow?

2. What is the pH range of alizarin yellow?  

1. Orange I guess...

2. What is the meaning of pH range?

[kevins]

1. right.

2.I mean the pH range of Colour of HIn and Colour of In-.