Define Protons
What is a positively charged subatomic particle found in the nucleus of an atom?
What is proposed that electrons move in specific energy levels around the nucleus?
Define Mass Number
What is the total number of protons and neutrons in an atom?
Find how many protons for Neon
What is 10?
Created the first atomic theory
Who is Democritus?
Define Neutrons
What is a subatomic particle with no charge found in the nucleus of an atom?
1897 - J.J. Thomson
What is discovered the electron and proposed the plum pudding model?
Define Atomic Number
What is the number of protons in an atom?
Find the number of electrons for H
What is 1?
Define Electrons
What is a negatively charged subatomic particle found outside the nucleus in energy levels or the electron cloud?
Define Atom
What is the smallest unit of matter that makes up an element and retains that element’s properties?
1926 - Electron Cloud Model (Schrödinger/Heisenberg)
What is electrons move in regions of probability, not fixed paths?
Define Element
What is a pure substance made of only one type of atom?
Find Mass Number of Fe
What is 56?
Write the nuclear form of Carbon-12
What is ¹²C?
Define Quarks
What is tiny particles that make up protons and neutrons?
1803 - John Dalton
What is proposed that all matter is made of tiny particles called atoms (solid sphere model)?
Define Isotopes
What is atoms of the same element that have the same number of protons but different numbers of neutrons?
Find the number of neutrons Be
What is 5?
Summarize the structure of an atom
What is an atom has a dense nucleus made of protons and neutrons, with electrons moving around the nucleus in energy levels or an electron cloud?
Define Valance Electrons
What is electrons in the outermost energy level of an atom?
1911 - Ernest Rutherford
What is atom is mostly empty space?
Define Average Atomic Mass
What is the weighted average of the masses of all naturally occurring isotopes of an element?
Find Atomic Number of Na
What is 11?
Explain difference of isotopes of the same element
What is they have different numbers of neutrons and different mass numbers?