## Do we need to memorize unit conversions? [ENDORSED]

004338125
Posts: 1
Joined: Fri Sep 20, 2013 3:00 am

### Do we need to memorize unit conversions?

Do we need to memorize the unit conversions?

For example:

nm = x10^-9m
pm = x10^-12m

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: Do we need to memorize unit conversions?  [ENDORSED]

Yes. You should have such unit conversions memorized.

For example, on a quiz you may be given the size of an object in nanometers. You must know how to convert this to the SI base unit meter for use in formulas (1 m = 10-9 nm).

Here is the list of commonly used metric prefixes:
• mega (M) : 106
• kilo (k) : 103
• hecto (h) : 102
• deca (da) : 101
• deci (d) : 10-1
• centi (c) : 10-2
• milli (m) : 10-3
• micro (μ) : 10-6
• nano (n) : 10-9

tinaZ
Posts: 6
Joined: Fri Sep 25, 2015 3:00 am

### Re: Do we need to memorize unit conversions?

For metric to metric unit conversions, yes, but for metric to US (i.g. meters to inches or mL to pints) you don't have to memorize.
also, 1cm^3=1mL

504549031
Posts: 17
Joined: Fri Sep 25, 2015 3:00 am

### Re: Do we need to memorize unit conversions?

What other unit conversions must be memorized for the exams in Chem 14A?

skalvakota2H
Posts: 52
Joined: Sat Jul 22, 2017 3:01 am

### Re: Do we need to memorize unit conversions?

Other conversions that may prove useful include:
1000mL = 1L, for volume analysis
1000 g = 1kg for mass analysis

Knowing the difference will make converting units easier when doing dimensional analysis.

Posts: 50
Joined: Fri Sep 29, 2017 7:05 am

### Re: Do we need to memorize unit conversions?

Should we also have the 3 temperature conversions memorized?

Sophie 1I
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am

### Re: Do we need to memorize unit conversions?

Some temperature conversions that are good to know:
When going from Celsius to Kelvin you add 273.15 to the temperature in Celsius (and subtract 273.15 going from kelvin to celsius)
Celsius= (Fahrenheit-32)x(5/9)

Lianna Kishi 1A
Posts: 23
Joined: Thu Jul 27, 2017 3:00 am

### Re: Do we need to memorize unit conversions?

Is there any easy way to remember metric prefixes? For example, a mnemonic that would help me remember what each one corresponds to or the order of them? Thanks!

Michelle Pham_3H
Posts: 26
Joined: Fri Sep 29, 2017 7:07 am

### Re: Do we need to memorize unit conversions?

One way that I remember metric prefixes is kind of antiquated and silly, but I learned it in middle school and I still use it now. It's an acronym called "King Henry Dances Up Down Chocolate Mountain", and it gives you the order of the metric prefixes from largest to smallest (kilo-, hecto-, deka-, etc). So what I normally do is I write the first letters down on paper (k h d u d c m) and you can use this to convert between the different prefixes. For example, if you have 3 grams and you need to convert it to milligrams, m is three milligrams to the right of u. That means you would move the decimal place 3 times to the right and you'd have 3,000 mg.

Dennisse Diaz 1D
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Joined: Mon Apr 09, 2018 1:39 pm
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### Re: Do we need to memorize unit conversions?

Does anyone know any helpful ways to memorize these conversions?