Atomic Structure
What do we call a substance made of only one type of atom?
An element
What does a period on the periodic table represent?
The number of shells
What is the electron configuration of oxygen?
2, 6, 0, 0
What change turns an atom into an ion?
Gaining or losing electrons
Which subatomic particle has a positive charge?
Proton
What are atoms mostly made of: solid matter or empty space?
Empty space
How many electrons are in a neutral atom of calcium?
20
Why does losing an electron create a positive ion?
More protons than electrons
How much does an Electron weigh?
~ 0 amu
How does the mass number differ from the atomic number?
Mass number = protons + neutrons; atomic number = protons, electrons
What are metalloids?
Elements that share both properties of Metals and Non Metals
What does an electron shell represent in an atom?
An energy level around the nucleus
A magnesium atom forms a 2+ ion. What happened to its electrons?
It lost two electrons
Which subatomic particle is considered Heavy?
Neutrons and Protons
What types of forces hold electrons together?
Electromagnetic Forces
Why do noble gases exist as single atoms rather than molecules?
Their outer shell is already full
What does the group number tell you?
Number of valence shell electrons
Is Na⁺ an Anion or Cation?
Cation
Why does a neutral atom have no overall charge?
Equal numbers of protons and electrons
An atom has mass number 23 and atomic number 11. How many neutrons?
12
Which group would you find an Ion that loses two electrons to become stable?
Group 2
Which element has an Electron Configuration of 2, 8, 6, 0?
Sulfur
How many electrons does P3- gain or lose?
Gains 3
Why does changing electron number form ions but changing neutron number does not?
Electrons affect charge; neutrons do not