the center of an atom which is made up of protons and neutrons
What is a nucleus?
200
What did Democritus' atomic model look like?
What is a sphere?
200
What defines an element?
What is the number of protons?
200
How many electrons can each orbital hold?
What is S= 2; P= 6; D= 10; F=14
200
How many protons, neutrons, and electrons does the element Iridium have?
What is 77, 115, 77
300
SI unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12 grams of carbon 12
What is a mole?
300
When did Thomson discover the electron and what did his model look like?
What is during a study of cathode rays; chocolate chip cookie?
300
What force holds the atoms together?
What is the electric force?
300
What makes an electron jump to a new energy level?
What is an atom's loss or gain of energy?
300
What is the atomic number and the average atomic mass of the element Xenon?
What is 79, 196.97
400
an electron in the outermost shell of an atom; determines chemical properties
What is a valence electron?
400
What did Rutherford discover?
What is a nucleus?
400
What is the difference between average atomic mass and mass number?
What is average atomic mass is the mean of all isotopes and mass number is specific to a single atom?
400
How many valence electrons does Nitrogen have?
What is 5?
400
How many moles does 15 grams of Nitrogen contain?
What is 1.07 mol?
500
a unit or quantum of light; a particle of electromagnetic radiation that has 0 rest mass and carries a quantum of energy
What is a photon?
500
What did Dalton add to the atomic theory?
What are atoms of a given element are identical and can join to form compounds?
500
What is Avagadro's number?
What is 6.02 x 10^23
500
How many total electrons can the first four energy levels hold?
What is 60?
500
What is the electron configuration for Potassium (K)?