Chemistry Test Vocab Flashcards
Dependent variable
y; the outcome. Then “then”
Hypothesis
An explanation that is based on prior scientific research or observations and that can be tested
Independent variable
x; causes the outcome. The “if”
Matter
Anything that has mass and takes up space
Chemical property
A property of matter that describes a substance’s ability to participate in chemical reactions
Ex: flammable? Soluble?
Chemical change
A change that occurs when one or more substances change into entirely new substances with different properties
Ex: catching on fire, two chemicals reacting,
Physical property
A characteristic of a substance that can be observed without involving a chemical change
Ex: color, luster, density, color, hardness
Physical change
A change of matter from one form to another without a change in chemical properties
Atom
The smallest unit of an element that maintains the properties of that element
Atomic number
The number of protons in the nucleus of an atom; the atomic number is the same for all atoms of an element
Isotope
An atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different mass); atoms the same element, but different mass
Mass number
The sum of the number of protons and neutrons in the nucleus of an atom
Charge, mass, and location of:
Electron
Negative
Very small
Electron cloud
Charge, mass, and location of:
Valence electron
Negative
Tiny
Outermost shell of atom
(determines the atom’s chemical properties)
Charge, mass, and location of:
Proton
Positive
1 amu
Nucleus
Charge, mass, and location of:
Neutron
No charge
1 amu
Nucleus
Gas
A form of matter that doesn’t have a definite volume or shape
Liquid
The state of matter that has a definite volume but not a definite shape
Solid
The state of matter in which the volume and shape of a substance are fixed
Fluid
A nonsolid state of matter in which the atoms are free to move past each other
Boiling
The conversion of a liquid to a vapor when the vapor pressure of the liquid equals atmospheric pressure
Freezing
Liquid to solid
Melting
Solid to liquid
Condensation
Gas to liquid
Sublimation
Solid to gas
Deposition
Gas to solid
Compound
A substance made up of atoms of two or more different elements joined by chemical bonds
Element
a substance that cannot be separated or broken down into simpler substances by chemical means
Mixture
a combination of two or more substances that are not chemically combined. Each element contains it’s own properties
Solution
a homogeneous mixture throughout which two or more substances are uniformly dispersed
solute
in a solution, the substance that dissolves in the solvent
Solvent
in a solution, the substance in which the solute dissolves
colloid
a mixture consisting of tiny particles that are intermediate in size between those in solutions and those in suspensions and that are suspended in a liquid, solid, or gas
Suspension
A homogeneous mixture that settles when standing and can be filtered
heterogeneous
not uniformly mixed; different parts have different characteristics
homogenous
uniform
molecule
the smallest physical unit of an element or compound
covalent bonding
a bond formed when atoms share one or more pairs of electron.
Happens with two non metals
ionic bonding
the attractive force between oppositely charged ions, which form when electrons are transferred from one atom to another
metallic bonding
a bond formed by the attraction between positively charged metal ions and the electrons around them
inert
having little or no ability to react
anion
ion with negative charge
cation
ion with positive charge
group
down, same # of valence electrons
period
right, energy levels
law of conservation of matter
matter cannot be created or destroyed in a natural chemical reaction
law of conservation of energy
energy cannot be created or destroyed in a natural chemical reaction
law of conservation of energy and matter
E=mc^2
law of conservation of charge
The net charge of an isolated system remains constant
density
mass/volume