Metric System and SI Unit Intro

Metric System and SI Unit Intro

Friday E-Learning

SI Units

• Scientists use the "International System of Units", also known as "SI Units"

• These are the units we use in lab

• In chemistry, we often use meters, kilograms, Kelvin, moles, and seconds

• These units are defined by fixed universal constants such as the speed of light in a vacuum

Multiple Choice

Which one of the following is a SI unit?

• foot

• kilogram

• clothing sizes

• fortnight

Scientific Notation

• A way to write very large and very small numbers

• Change it to a number between 1-10 that's multiplied by a power of 10

• Ex: Write 504,000,000 in scientific notation

• 5.04 x 10^8

• 
  

Multiple Choice

Which of the following is correctly written in scientific notation?

• 3.14 x 10^9

• 0.00314 x 10^12

• 314 x 10^7

• 3,140,000,000

Metric Prefixes

• With SI units, we use standard prefixes

• Prefixes go in front of a word

• Ex: kilogram vs milligram

• SI units are all based off of powers of 10

• So a millimeter is 10x smaller than a centimeter

Multiple Choice

Which one of the following is NOT a metric prefix?

• kilo-

• milli-

• pre-

• centi-