Chem equilibria Thiosulfate Q

The apparatus in the figure below was set up to measure the time taken for 20.0 cm of sodium thiosulfate solution to react with 5.0 cm of hydrochloric acid in a 100 cm° conical flask at 20 °C.
The timer was started when the sodium thiosulfate solution was added to the acid in the flask.
The timer was stopped when it was no longer possible to see the cross on the paper.

b) The experiment was repeated at 20 °C using a 250cm3 conical flask - which statement is correct?

A: The time taken would be increased by using larger conical flask??

Surely if conc and vol are kept constant there is no change? I dont understand at all lol.

Reply 1

ineedallthehelp

4

Hey so my initial thoughts are that because it’s a bigger flask it’s a larger area for the solid ppt to appear over and cover the cross. It wont be forming in as deep amount of solution so would not become as opaque as quickly to prevent you seeing the cross? Hopefully that makes a little sense and again I’m not sure if that’s correct but it’s my first thought when I read it :smile:

Reply 2

uhhhh6678987654

OP

12

i did wonder that- is that likely?

Original post by ineedallthehelp

Hey so my initial thoughts are that because it’s a bigger flask it’s a larger area for the solid ppt to appear over and cover the cross. It wont be forming in as deep amount of solution so would not become as opaque as quickly to prevent you seeing the cross? Hopefully that makes a little sense and again I’m not sure if that’s correct but it’s my first thought when I read it :smile:

Reply 3

ineedallthehelp

4