Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Chem CH2 Section 1

Chemistry CH2 Section 1 Atoms and Their Structures

atom the smallest particle of a given type of matter
atomic mass unit one-twelfth the mass of a carbon-12 atom
atomic number the number of protons in the nucleus of an atom of an element
atomic theory the idea that matter is made up of fundamental particles called atoms
electron negatively charged particle
experiment a set of controlled observations that test a hypothesis
hypothesis a prediction that can be tested to explain observations
isotope any of two or more atoms of an element that are chemically alike but have different masses
law of definite proportions the principle that the elements that comprise a compound are always in a certain proportion by mass
mass number the sum of the neutrons and protons in the nucleus of an atom
neutron a subatomic particle with a mass equal to a proton but with no electrical charge
nucleus the small, dense, positively charged central core of an atom
proton a positively charged subatomic particle
scientific law a fact of nature that is observed so often that it is accepted as the truth
scientific method a systematic approach used in scientific study; an organized process used by scientists to do research and verify the work of others
theory an explanation based on many observations and supported by the results of many experiments