mrstripedshades
Active Member
- Joined
- May 25, 2015
- Messages
- 466
- Gender
- Male
- HSC
- 2016
Lol my maths was damn average as always :/ honestly find the HSC prac papers easier when i was doing them. There was so much shapes and shit, my worst enemy in maths by far fml I swear my teachers love geo
Still think I did okay though and that with some silly errors, it was generally a normal test, I was kinda shocked that people thought it was that hard. The multiple choice was so damn easy too.
Also if theres any chem fam online that can quickly tell me if my answer for this would be okay.
Justify anhydrous sodium carbonate as a primary standard :
Anhydrous sodium carbonate is a weak base that is soluble, equipping it to be a good primary standard. It also has a relatively high molar mass, minimising any errors in calculation or weighing. It does not change on exposure to the atmosphere as it is anhydrous and not deliquescent, hence it does not contain any extra water or absorb any water from the air. This stability also assists in it being weighed accurately, hence being a good primary standard to test. It's also available very pure. All this together justifies its use as a primary standard.
Still think I did okay though and that with some silly errors, it was generally a normal test, I was kinda shocked that people thought it was that hard. The multiple choice was so damn easy too.
Also if theres any chem fam online that can quickly tell me if my answer for this would be okay.
Justify anhydrous sodium carbonate as a primary standard :
Anhydrous sodium carbonate is a weak base that is soluble, equipping it to be a good primary standard. It also has a relatively high molar mass, minimising any errors in calculation or weighing. It does not change on exposure to the atmosphere as it is anhydrous and not deliquescent, hence it does not contain any extra water or absorb any water from the air. This stability also assists in it being weighed accurately, hence being a good primary standard to test. It's also available very pure. All this together justifies its use as a primary standard.