Also did they ask to show the equivalence point on that ph curve btw? Like I just drew a curve with two vertical sections at 10 and 20 cm3 at the respective pka=ph values? Do you think that would be correct?

Reply 125

Maria247

1

Original post by Blazyy

Straight line = Zero order
A straight line is first order only if you plot a graph of rate against concentration.

That was a rate concentration graph.

Reply 126

Sandy_Vega30

9

But 1000/ t is directly proportional to initial rate of reaction while volume of IO3- is directly proportional to concentration. SO technically it's like a graph of rate against concentration. Hence, it's first order. My teacher confirmed it after seeing the paper. :smile:

Reply 127

12103763d

10

First stuff, the graph I drew is 1000/t against volume, '/' is missing in the table for 1000/t that I wanted to raise my hand to tell this mistake to invigilator, as the question provided that rate is proportional to 1/t, so you can think the vertical part is the rate of reaction. For the horizontal part, yes it's the volume of that ion, some past papes of this unit needed candidate to figure out volume can be 'imitated' to concentration if total volume is constant, so in overall the graph is like rate against concentration and I got a straight line through the origin, its first order. It's my opinion idk if it's correct

Reply 128

Maria247

1

Original post by Sandy_Vega30

But 1000/ t is directly proportional to initial rate of reaction while volume of IO3- is directly proportional to concentration. SO technically it's like a graph of rate against concentration. Hence, it's first order. My teacher confirmed it after seeing the paper. :smile:

How did you meausre the volume? Using a pipette or measuring cylinder?

Reply 129

skeletonboy1

1

i wrote syringe.. since i thought pipette isn't allowed since it's used for sulfate ions or some sort... did sth like that in pastpapers im not sure

Reply 130

Sandy_Vega30

9

Original post by Maria247

How did you meausre the volume? Using a pipette or measuring cylinder?

Volume of what?

Reply 131

Maria247

1

Original post by Sandy_Vega30

Volume of what?

Iodate(V)

I said syringe too.

Rhombic Sulphur entropy question? Although the equation said "S (Rhombic) + 3F2......", the data booklet suggests that Sulpher Rhombic generally consists as 8 Sulphur atoms. So do we multiply the molar entropy of S rhombic by 8?

Reply 134

12103763d

10

It's just a few amount it added, below 10cm3, even if not pipette, it should be biurette but not measuring cylinder. I may be wrong though

Reply 135

Geethan

1

Original post by Blazyy

It was 5 marks, I think you'll get 2 or 3. What about the nmr spectra of propanoic acid? It had 3 peaks right, 2 triplets and 1 quartet

Yer it had 3 peaks. But I think i ended up with one quadruplet, a triplet and a singlet o.O

Reply 136

12103763d

10

Original post by Geethan

Rhombic Sulphur entropy question? Although the equation said "S (Rhombic) + 3F2......", the data booklet suggests that Sulpher Rhombic generally consists as 8 Sulphur atoms. So do we multiply the molar entropy of S rhombic by 8?