I am the smallest unit of matter that cannot be broken down by chemical means
What is an atom
100
The attractive force between oppositely charged ions
What is an ionic bond
100
One way that atoms bond is by sharing ____________ electrons to form a covalent bond.
What is valence
100
Plays an important role in many of the molecules that make up living things
What is hydrogen bonding
100
Humans can survive for a few weeks without food but only a few days without this
What is water
200
The center of an atom made up of protons and neutrons
What is a nucleus
200
Atoms can achieve a stable valence level by __________ or __________ electrons.
What is losing or gaining
200
A group of atoms held together by a covalent bond.
What is a molecule
200
Water droplets sticking together rather than being spread out is an example of being ___________________.
What is cohesive
200
Every living or non-living thing that takes up space and has mass
What is matter
300
Has a negative charge and orbits the nucleus
What is an electron
300
Table salt is made up of these two elements
What is sodium and chlorine
300
H2O is made up of three atoms called ________________, _________________ and __________________.
What is hydrogen, hydrogen and oxygen
300
Because hydrogen bonding is so strong, it takes a large amount of _____________ to break the bonds.
What is energy
300
A substance that cannot be separated or broken down into simpler substances by chemical means
What is an element
400
Is in the outermost energy level and can be gained, lost or shared in order to form bonds
What is a valence electron
400
An atom or group of atoms that has an electric charge because it has gained or lost electrons
What is an ion
400
Molecules with partial charges on opposite ends are said to be this
What is polar
400
When bonded to an oxygen nitrogen or fluorine atom, a hydrogen atom has a partial charge nearly as great as this particles charge.
What is a proton
400
A force of attraction that holds atoms together and are usually created by a transfer or sharing of one or more electrons
What is a bond
500
A particle found in the nucleus with a positive charge is a ______________ and a particle found in the nucleus with no charge at all is a ________________.
What is a proton and a neutron
500
A sodium atom readily gives up one electron to chlorine. The sodium atom is now a ___________________.
What is sodium ion
500
Molecules made of two oxygen atoms sharing electrons in a covalent bond
What is oxygen in the air that we breathe
500
Attraction of particles of different substances
What is adhesion
500
Most atoms become stable when they have this many valence electrons in the outer shell.