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March 29, 2024, 11:30:50 am

Author Topic: HSC Chemistry Question Thread  (Read 1040699 times)  Share 

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g.xzhu

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Re: Chemistry Question Thread
« Reply #3660 on: November 12, 2018, 10:30:33 pm »
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Hello!

Could I please have some help with this question?

Calculate the molar solubility of magnesium phosphate (in mol/L), given that its Ksp is 1.04 x 10-24.


I keep getting 6.26 x 10-6 as my answer...

Thanks!

horse9996

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Re: Chemistry Question Thread
« Reply #3661 on: November 14, 2018, 12:48:18 pm »
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Hello!

Could I please have some help with this question?

Calculate the molar solubility of magnesium phosphate (in mol/L), given that its Ksp is 1.04 x 10-24.


I keep getting 6.26 x 10-6 as my answer...

Thanks!

https://www.chemguide.co.uk/physical/ksp/calculations.html
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david.wang28

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Re: Chemistry Question Thread
« Reply #3662 on: November 14, 2018, 10:11:14 pm »
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Hello,
I need help with the questions in the pictures I sent Exercise 3 (14 c and d and question 15 a and b and 16). Can anyone please give me a detailed reply ASAP? Thanks :)
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g.xzhu

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Re: Chemistry Question Thread
« Reply #3663 on: November 17, 2018, 07:43:47 pm »
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Hello,
I need help with the questions in the pictures I sent Exercise 3 (14 c and d and question 15 a and b and 16). Can anyone please give me a detailed reply ASAP? Thanks :)

Hopefully these help! Please tell me if any of my answers are wrong

[Q15 a, b]
« Last Edit: November 17, 2018, 07:56:18 pm by g.xzhu »

g.xzhu

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Re: Chemistry Question Thread
« Reply #3664 on: November 17, 2018, 07:54:12 pm »
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Hello,
I need help with the questions in the pictures I sent Exercise 3 (14 c and d and question 15 a and b and 16). Can anyone please give me a detailed reply ASAP? Thanks :)

[Q14, Q16]
« Last Edit: November 17, 2018, 07:56:47 pm by g.xzhu »

david.wang28

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Re: Chemistry Question Thread
« Reply #3665 on: November 17, 2018, 10:25:15 pm »
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Hopefully these help! Please tell me if any of my answers are wrong

[Q15 a, b]
Thanks for the answers! :)
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SebastianHabibi

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Re: Chemistry Question Thread
« Reply #3666 on: November 28, 2018, 08:33:06 pm »
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Soooooo,
For my chemistry assessment this term we have to write a depth study regarding module 5. The aim of my investigation is to "determine the effect of concentration and temperature on the position of the equilibrium, and therefore yield of iron thiocyanate.
I want to determine which will be most effective for maximising yield, concentration or temperature. To do this, I conducted two experiments one with varying concentrations and one with varying temperatures. I'm not exactly sure how to write my variables table because I have two experiments. What would my independent variable be? OR do I have to make two variables tables? Help I'm confused

kauac

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Re: Chemistry Question Thread
« Reply #3667 on: November 28, 2018, 09:17:56 pm »
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Soooooo,
For my chemistry assessment this term we have to write a depth study regarding module 5. The aim of my investigation is to "determine the effect of concentration and temperature on the position of the equilibrium, and therefore yield of iron thiocyanate.
I want to determine which will be most effective for maximising yield, concentration or temperature. To do this, I conducted two experiments one with varying concentrations and one with varying temperatures. I'm not exactly sure how to write my variables table because I have two experiments. What would my independent variable be? OR do I have to make two variables tables? Help I'm confused

Hi...
You will have two independent variables in this set-up, since there are technically two different experiments. Concentration is one independent variable, and temperature is another independent variable, as independent variables can be identified as the one that is altered through the course of the experiment. Yield is your dependent variable, as its results will change according to concentration and temperature.

It would be best to have two separate variable tables - as 1 table with 2 independent variables could make the experiment look invalid. Hope this makes sense.  :)
« Last Edit: November 28, 2018, 10:06:15 pm by kauac »
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jazcstuart

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Re: Chemistry Question Thread
« Reply #3668 on: November 28, 2018, 09:41:17 pm »
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Soooooo,
For my chemistry assessment this term we have to write a depth study regarding module 5. The aim of my investigation is to "determine the effect of concentration and temperature on the position of the equilibrium, and therefore yield of iron thiocyanate.
I want to determine which will be most effective for maximising yield, concentration or temperature. To do this, I conducted two experiments one with varying concentrations and one with varying temperatures. I'm not exactly sure how to write my variables table because I have two experiments. What would my independent variable be? OR do I have to make two variables tables? Help I'm confused
I would agree with kauac, you would need to think about them as 2 separate experiments, one where you are varying concentration and one varying temperature. You could use 2 separate tables, but the dependent and controlled variables should still be the same, so another option could be to use one table and label the independent variables for each experiment (if you are concerned about having 2 tables). So for example your independent variable column would say:

Experiment 1: concentration
Experiment 2: temperature

Good luck!
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mirakhiralla

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Re: Chemistry Question Thread
« Reply #3669 on: December 03, 2018, 08:42:03 pm »
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hey I have a q but it won't let me upload the photo of it because its too big,
how do I show it to you?

sweetiepi

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Re: Chemistry Question Thread
« Reply #3670 on: December 03, 2018, 08:43:37 pm »
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hey I have a q but it won't let me upload the photo of it because its too big,
how do I show it to you?
Hey there, you can upload it to an image-sharing site such as http://www.imgur.com and share the link with us! :))
« Last Edit: December 03, 2018, 08:47:25 pm by insanipi »
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scienceislife

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Re: Chemistry Question Thread
« Reply #3671 on: December 12, 2018, 02:51:57 pm »
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Given the concentration of ethanoic acid through an esterification reaction, how do you find the corresponding concentrations of ethanol when you aren't given a volume?

david.wang28

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Re: Chemistry Question Thread
« Reply #3672 on: December 15, 2018, 05:17:47 pm »
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Given the concentration of ethanoic acid through an esterification reaction, how do you find the corresponding concentrations of ethanol when you aren't given a volume?
Do you have the number of moles given to you? If you do, you can find the volume and then go on and find the concentration of ethanol. I'm not exactly sure if this is the right answer, but from what you said, that is how I tried to get my answer out.
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jasn9776

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Re: Chemistry Question Thread
« Reply #3673 on: December 22, 2018, 01:09:05 pm »
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DIY bridging course question: i understand why certain atoms form certain cations. e.g. Na forms 1+ cations to gain the same electron structure as its closest noble gas(Neon) by losing an electron. However what about Silver ions and stuff? Is there a reason i have to know or is it just how it is? (see attached 'common additional cations')
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kauac

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Re: Chemistry Question Thread
« Reply #3674 on: December 22, 2018, 03:00:29 pm »
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DIY bridging course question: i understand why certain atoms form certain cations. e.g. Na forms 1+ cations to gain the same electron structure as its closest noble gas(Neon) by losing an electron. However what about Silver ions and stuff? Is there a reason i have to know or is it just how it is? (see attached 'common additional cations')

Hi...Just going to give a little bit of an explanation of behind the formation of ions, so that it might make sense for silver.

So you will find that the formation of of both cations and anions works by the number of electrons in the valency shell (outermost shell) of an atom. Valency works according to the periodic table, so that Group I has a valency of 1, Group II has a valency of 2, Group III has a valency of 3, and so on. Thus, elements in Group I will form 1+ cations, Group II: 2+ cations, Group III: 3+ cations, and for the otherside of the table, Group VIII: -1 anion, Group VII: -2 anions, etc.

Since silver is a transitional metal (i.e. it is not in one of the 8 specified groups), it does not have a set ion that it forms. It can form both cation Ag+ and Ag 2+. However, the Ag 2+ is quite rare and only forms under certain conditions, so therefore it is most common to use the Ag+ cation when referring to the ion for silver.

Hope this helps! :)
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