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I have a question in A/Level Chemistry IAL Edexcel Unit 4, Please help me

15 Information about four samples of acid is shown below.Sample 1: 1.0 mol dm–3 HClSample 2: 1.0 mol dm–3 H2SO4 Sample 3: 0.1 mol dm–3 HCl Sample 4: 0.1 mol dm–3 CH3COOH Which of the following lists shows the samples in order of increasing pH?Please someone explain this to me, I really appreciate it
Original post by dunuraperera
15 Information about four samples of acid is shown below.Sample 1: 1.0 mol dm–3 HClSample 2: 1.0 mol dm–3 H2SO4 Sample 3: 0.1 mol dm–3 HCl Sample 4: 0.1 mol dm–3 CH3COOH Which of the following lists shows the samples in order of increasing pH?Please someone explain this to me, I really appreciate it

This is a question from January 2011 Unit 4 Chemistry IAL Edexcel Syllabus
Original post by dunuraperera
15 Information about four samples of acid is shown below.Sample 1: 1.0 mol dm–3 HClSample 2: 1.0 mol dm–3 H2SO4 Sample 3: 0.1 mol dm–3 HCl Sample 4: 0.1 mol dm–3 CH3COOH Which of the following lists shows the samples in order of increasing pH?Please someone explain this to me, I really appreciate it

Copy-paste much?

Here, let me format that for you to make it (slightly more) intelligible.

Information about four samples of acid is shown below.

Sample 1: 1.0 mol dm–3 HCl
Sample 2: 1.0 mol dm–3 H2SO4
Sample 3: 0.1 mol dm–3 HCl
Sample 4: 0.1 mol dm–3 CH3COOH

Which of the following lists shows the samples in order of increasing pH?

However, it remains rather pointless without the "following lists".
Original post by charco
Copy-paste much?

Here, let me format that for you to make it (slightly more) intelligible.

Information about four samples of acid is shown below.

Sample 1: 1.0 mol dm–3 HCl
Sample 2: 1.0 mol dm–3 H2SO4
Sample 3: 0.1 mol dm–3 HCl
Sample 4: 0.1 mol dm–3 CH3COOH

Which of the following lists shows the samples in order of increasing pH?

However, it remains rather pointless without the "following lists".

Thanks I really appreciate it
Original post by charco
Copy-paste much?

Here, let me format that for you to make it (slightly more) intelligible.

Information about four samples of acid is shown below.

Sample 1: 1.0 mol dm–3 HCl
Sample 2: 1.0 mol dm–3 H2SO4
Sample 3: 0.1 mol dm–3 HCl
Sample 4: 0.1 mol dm–3 CH3COOH

Which of the following lists shows the samples in order of increasing pH?

However, it remains rather pointless without the "following lists".

Which of the following lists shows the samples in order of increasing pH?

A 1, 2, 3, 4

B 4, 3, 2, 1

C 2, 1, 3, 4

D 4, 3, 1, 2
Original post by dunuraperera
Which of the following lists shows the samples in order of increasing pH?

A 1, 2, 3, 4

B 4, 3, 2, 1

C 2, 1, 3, 4

D 4, 3, 1, 2

Which do you think? and why?
Original post by charco
Which do you think? and why?

Im not exactly sure of the answer, Because I am confused with the concept of the strength of acidity, I believe the answer is 'C', Because An acid's strength is dependant on its ability to lose protons. I need an explanation of how to determine
Original post by dunuraperera
Im not exactly sure of the answer, Because I am confused with the concept of the strength of acidity, I believe the answer is 'C', Because An acid's strength is dependant on its ability to lose protons. I need an explanation of how to determine

An acid's strength is given by its pKa value. The lower the value the stronger the acid.
The pKa value is the negative log of the acid dissociation constant. The greater the dissociation the stronger the acid.
So called "strong" acids are 100% dissociated in aqueous solution - the mineral acids.
In weak acids dissociation is affected by two factors:
1. The strength of the O-H bond, which in turn is a function of the electron density in the bond.
2. The stability of the conjugate base.
Original post by charco
An acid's strength is given by its pKa value. The lower the value the stronger the acid.
The pKa value is the negative log of the acid dissociation constant. The greater the dissociation the stronger the acid.
So called "strong" acids are 100% dissociated in aqueous solution - the mineral acids.
In weak acids dissociation is affected by two factors:
1. The strength of the O-H bond, which in turn is a function of the electron density in the bond.
2. The stability of the conjugate base.

Thanks, For this question, how will it be applied, if you could kindly explain
Original post by dunuraperera
Thanks, For this question, how will it be applied, if you could kindly explain

1,2 and 3 are all strong acids
but 2 is diprotic and so releases more hydrogen ions in solution (but that does not make it a stronger acid, per se, it just makes the pH lower)
4 is a weak acid.
1 and 3 you simply compare the concentrations
Original post by charco
1,2 and 3 are all strong acids
but 2 is diprotic and so releases more hydrogen ions in solution (but that does not make it a stronger acid, per se, it just makes the pH lower)
4 is a weak acid.
1 and 3 you simply compare the concentrations

Thank You so much, It really helped, And also thank you for the fast replies

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