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


7th Grade Physical Science

The smallest particle into which an element can be divided and still be the same element. atom
The tool scientists used to see very small things. microscope
The theory created by John Dalton that said all matter is made up of atoms. The Atomic Theory
Particles within the atom that have a negative charge. electrons
A small, dense center inside of atoms that have a positive charge and surrounded by electrons. nucleus
Ernest Rutherford discovered that the nucleus is made up of smaller, positive charged particles called ? protons
A model created by Niels Bohr that explains how electrons in atoms behave (move). Bohr's model
Scientists James Chadwick discovered that a nucleus contains uncharged particles called ? neutrons
Electrons move within an area around the nucleus called ? electron cloud
The number of protons in the nucleus of an atom. atomic number
The number of protons and neutrons in an atom's nucleus is called? mass number