Base Units

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304655635
Posts: 9
Joined: Fri Sep 25, 2015 3:00 am

Base Units

Postby 304655635 » Wed Oct 04, 2017 1:39 pm

So if I have an answer to a problem that isn't in base units, should I convert the answer to base units even if the question gives me a different unit?

Hope that makes sense!

Chem_Mod
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Re: Base Units

Postby Chem_Mod » Wed Oct 04, 2017 1:49 pm

It depends on the question. I am assuming that by base units you mean standard units. If the question does not ask for a specific unit that your answer HAS to be in, and the question stem provides you a unit, then it is best to present your answer in the units given. If the problem neither specifies a unit for the answer nor provides a number in a unit, then you should probably ask for further clarification.

As always, make sure to keep track of your units ESPECIALLY when you are using constants (like speed of light, or Planck's constant)

Matthew Lee 3L
Posts: 51
Joined: Fri Sep 29, 2017 7:07 am

Re: Base Units

Postby Matthew Lee 3L » Wed Oct 04, 2017 3:50 pm

I think that, like the post above said, if it says in the question what units it wants the answer in, use those units. However, if it does not say what units to use, and it has only base units in the question, I would use the base units just to be safe.

Yixin Angela Wang 2H
Posts: 51
Joined: Thu Jul 27, 2017 3:00 am

Re: Base Units

Postby Yixin Angela Wang 2H » Wed Oct 04, 2017 10:12 pm

Additionally, a lot of formulas are given in specific, usually SI units. For example, temperature is usually in Kelvins in formulas, but it is in Celsius when you measure it. In that case, to use the formula correctly, you have to convert Celsius to Kelvin.

Mia Navarro 1D
Posts: 52
Joined: Fri Sep 29, 2017 7:04 am

Re: Base Units

Postby Mia Navarro 1D » Wed Oct 04, 2017 11:03 pm

Something Dr. Lavelle mentioned in class today about temperature units may help you determine which to use when not specified.
As aforementioned, Celsius is more commonly used to measure the temperature, whereas Kelvin is more commonly used in calculations. I presume this is so because Kelvin units never go below zero, and Celsius and Kelvin are easily interchangeable. When using Kelvin, make sure to remember the number 273.15, as this is the freezing point and the number added to the Celsius temperature to convert to Kelvin.

Hope this helps!

Mia Navarro

Wayland Leung
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Re: Base Units

Postby Wayland Leung » Thu Oct 05, 2017 3:36 pm

It really all just depends on the problem and what it asks you to find. If the question is asking for the amount of product that can be prodced in grams, and you end up with moles of the product, you should multiply that amount by the molar mass to get the answer in terms of grams.

torialmquist1F
Posts: 49
Joined: Sat Jul 22, 2017 3:00 am

Re: Base Units

Postby torialmquist1F » Fri Oct 06, 2017 2:33 pm

You only have to convert to base units if they ask for it in the answer. Also, some equations will require you to convert before solving such as the molarity equation because you have to divide by liters.


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