## units for mass

$\lambda=\frac{h}{p}$

rileygilbertson
Posts: 17
Joined: Mon Oct 02, 2017 7:18 am

### units for mass

Why is the SI unit for mass kilograms? What other equations mandate the use of kilograms?
Last edited by rileygilbertson on Sun Oct 22, 2017 8:02 pm, edited 1 time in total.

Josh Moy 1H
Posts: 58
Joined: Thu Jul 13, 2017 3:00 am

### Re: units for mass

because joules is per kilogram

SitharaMenon2B
Posts: 50
Joined: Thu Jul 27, 2017 3:01 am

### Re: units for mass

The De Broglie equation $\lambda=\frac{h}{mv}$ and the equation for kinetic energy $E_{k}=\frac{1}{2}mv^2$ both require mass (m) to be in kilograms

lauren chung 2f
Posts: 50
Joined: Fri Sep 29, 2017 7:03 am

### Re: units for mass

You only have to use kilograms as your units when you are doing an equation that has joules in it since a joule is equivalent to kg^2m^2/s^2.

Chem_Mod
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### Re: units for mass

It's Joule because of kilogram, not kilogram because of joule. Convert m to kg everywhere unless there are molar mass there.

Posts: 16
Joined: Sat Jul 09, 2016 3:00 am

### Re: units for mass

what are the unit conversions for kilojoules (K.J) in meters per second?

Chem_Mod
Posts: 18153
Joined: Thu Aug 04, 2011 1:53 pm
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### Re: units for mass

meters per second is not a unit for energy. Therefore you cannot do the conversion.