Acids and Bases question (1 Viewer)

adomad

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how would you do this question
Q1: Rank these solutions from lowest to highest pH:
0.1mol l^-1 acetic acid
0.1mol l^-1 hydrochloric acid
0.1mol l^-1sodium hydroxide
0.1mol l^-1sulfuric acid
0.1mol l^-1 ammonia solution

Q2: Rank these solutions in order from best to poorest conductor of electricity and justify your answer
0.005M acetic acid
0.1M sodium hydroxide
0.5M sulfuric acid
0.05M hydrochloric acid
0.1M calcium hydroxide

my teacher just gave me these to do and she didn't really explain it. all i know is that a strong acid is able to full ionise (dissociate) and this makes them good conductors.... Just a quick question, does the molarity matter as strong and concentrated are different things....


cheers,

ADomad:D
 

bored of sc

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how would you do this question
Q1: Rank these solutions from lowest to highest pH:
0.1mol l^-1 acetic acid
0.1mol l^-1 hydrochloric acid
0.1mol l^-1sodium hydroxide
0.1mol l^-1sulfuric acid
0.1mol l^-1 ammonia solution
Not sure about 2.

For this question (lowest - highest pH), they are all the same concentration so:
- Sulfuric acid - strong diprotic acid.
- Hydrochloric acid - strong monoprotic.
- Acetic Acid - weak acid.
- Ammonia solution - weak base.
- Sodium Hydroxide - strong base.

Get someone smarter to check this though.
 

shady145

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how would you do this question
Q1: Rank these solutions from lowest to highest pH:
0.1mol l^-1 acetic acid
0.1mol l^-1 hydrochloric acid
0.1mol l^-1sodium hydroxide
0.1mol l^-1sulfuric acid
0.1mol l^-1 ammonia solution

Q2: Rank these solutions in order from best to poorest conductor of electricity and justify your answer
0.005M acetic acid
0.1M sodium hydroxide
0.5M sulfuric acid
0.05M hydrochloric acid
0.1M calcium hydroxide

my teacher just gave me these to do and she didn't really explain it. all i know is that a strong acid is able to full ionise (dissociate) and this makes them good conductors.... Just a quick question, does the molarity matter as strong and concentrated are different things....


cheers,

ADomad:D
question one you can simply use calculations to determine the answer
question 2...use prelim knowledge... ionic compounds conduct electricity in solution also more ions, easier it conducts electricity,(conduction occurs through electrons moving so charges praticles allow an electron to move through) so work out which will have the most ions, and also use your HSC knowledge to recognise which substances ionise completely and which only ionise partly.
i havnt had a question like this before so what i jsut said may be incorrect =/ thats just what i think
 

shady145

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Not sure about 2.

For this question (lowest - highest pH), they are all the same concentration so:
- Sulfuric acid - strong diprotic acid.
- Hydrochloric acid - strong monoprotic.
- Acetic Acid - weak acid.
- Ammonia solution - weak base.
- Sodium Hydroxide - strong base.

Get someone smarter to check this though.
thats right
 

adomad

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Not sure about 2.

For this question (lowest - highest pH), they are all the same concentration so:
- Sulfuric acid - strong diprotic acid.
- Hydrochloric acid - strong monoprotic.
- Acetic Acid - weak acid.
- Ammonia solution - weak base.
- Sodium Hydroxide - strong base.

Get someone smarter to check this though.
so if it donates more protons, then it is a beetter conductor? i already knew the order (without looking at the answers lol) but i just want to know if there is a general rule, or is it something you must memorise?


question one you can simply use calculations to determine the answer
question 2...use prelim knowledge... ionic compounds conduct electricity in solution also more ions, easier it conducts electricity,(conduction occurs through electrons moving so charges praticles allow an electron to move through) so work out which will have the most ions, and also use your HSC knowledge to recognise which substances ionise completely and which only ionise partly.
i havnt had a question like this before so what i jsut said may be incorrect =/ thats just what i think
the answer is

0.5M sulfuric acid
0.1M calcium Hydroxide
0.1M sodium hydroxide
0.05M HCl
0.05M acetic acid

so the moles/litre do needed to be taken into account. i guess that is right cause the more ions, the more electron transfers yeah? Again, is there a general rule?
 

shady145

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so if it donates more protons, then it is a beetter conductor? i already knew the order (without looking at the answers lol) but i just want to know if there is a general rule, or is it something you must memorise?




the answer is

0.5M sulfuric acid
0.1M calcium Hydroxide
0.1M sodium hydroxide
0.05M HCl
0.05M acetic acid

so the moles/litre do needed to be taken into account. i guess that is right cause the more ions, the more electron transfers yeah? Again, is there a general rule?
i suppose if there was a general rule it would be somthing like, more ion=more conductivity
and yes concentration needs to be taken into account todetermine hwich one has most ions
 

adomad

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ok another question, how can you tell if a reaction is exothermic or endo?? for example, co2 +h20 --> h2CO3 and this reaction is somehow exothermic?? is there someing about proton transfer because i remember reading something about it HELP

thanks,
 

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