## Clarification on the Vitamin C Example

Sunia Akaveka 4I
Posts: 67
Joined: Sat Sep 14, 2019 12:17 am
Been upvoted: 1 time

### Clarification on the Vitamin C Example

In the example given in class regarding 8.00g of Vitamin C, where the carbon amounted to 3.27g, hydrogen amounted to 0.366g, and oxygen was 4.36g, Dr. Lavelle emphasized the importance of double-checking that the sum of these amounts equal to the 8.00g. When adding these, you receive a total of 7.996g. What happens to the 0.004g that is allegedly accounted for?

andrewcj 2C
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

### Re: Clarification on the Vitamin C Example

My best guess would be that rounding caused the masses of the individual elements to be a little smaller than they really are, which creates a small discrepancy in the summed mass and the total mass. In real life, our instruments are not always perfect, and this might be trying to show that.

Ryan 1K
Posts: 101
Joined: Fri Aug 09, 2019 12:15 am

### Re: Clarification on the Vitamin C Example

Elaborating on the rounding aspect, all the numbers provided have three significant figures. Since one of the numbers is less than 1, it makes sense for there to be some small mass lost in the calculations as the other numbers would be rounded.

Posts: 53
Joined: Wed Sep 11, 2019 12:17 am

### Re: Clarification on the Vitamin C Example

I think the small amount 'lost' is due to rounding - if we went out further in the decimal places then we would likely have gotten a value slightly closer to 8.000. Additionally, in real life we will nearly always be slightly off of the theoretical value, due to things like solution sticking to the beaker or other instruments, weighing issues, etc.

Sunia Akaveka 4I
Posts: 67
Joined: Sat Sep 14, 2019 12:17 am
Been upvoted: 1 time

### Re: Clarification on the Vitamin C Example

So, if this 0.004g is lost to discrepancy or for rounding purposes, wouldn’t this further our mass percentage composition data from accuracy? Would this be more considered precision?

Katie Bart 1I
Posts: 104
Joined: Sat Aug 24, 2019 12:16 am

### Re: Clarification on the Vitamin C Example

It would, but we have to make sure we account for significant figures. Also, we lose precision every time we round so this isn't significantly worse than other problems we have done.

504939134
Posts: 103
Joined: Wed Sep 18, 2019 12:21 am

### Re: Clarification on the Vitamin C Example

I believe this was because we are supposed to round up.

### Who is online

Users browsing this forum: No registered users and 1 guest