Chemistry Flashcards
What is chemistry?
A study of matter.
What is matter?
Anything that takes up space and has mass.
What points are in the particle theory of matter?
-particles are constantly moving
-particles are extremely tiny
-particles determine what kind of matter something is
What are elements?
Elements are things that cannot be broken down and are made up of atoms.
What are molecules?
Two elements chemically combined
What are compounds?
Compounds are things made up of molecules.
What are substances?
Substances are things made up of only one particle.
What are mixtures?
Mixtures are made of two or more types of particles that are not chemically bonded.
What are homogeneous mixtures?
Also known as solutions, these are mixtures containing only true particles and is when one substance is dissolved in another.
What are alloys?
Alloys are homogeneous mixtures of metal.
What are heterogeneous mixtures?
Also known as a mechanical mixture, these are not made up of true particles and have bits in them.
What is a suspension?
A suspension is when bits are dispersed in a liquid and will eventually settle from gravity.
What are colloids?
A type of heterogeneous mixture with bits so small they never settle.
What is a physical property?
A property that can be observed without changing the material.
What are physical changes?
Changes that can be made without changing the particles in a material.
How can you tell if a chemical change has occurred?
-gas is produced
-temperature changes
-quick colour change
-formation of precipitate (a solid forms)
-the change cannot be reversed
What are the diatomic elements?
Hydrogen, oxygen, fluorine, bromine, iodine, nitrogen, chlorine
Who developed the first atomic theory of matter?
John Dalton
What is in John Daltons Atomic theory of matter?
-elements are made of indivisible, indestructible particles
-atoms of the same element are exactly alike
-atoms of different elements are different
-compounds are made by joining two or more elements
Who discovered electrons?
J.J Thomson
What is Thomsons model called?
The raisin bun model
What did Ernest Rutherford discover?
Protons, neutrons, and the nucleus
What is Rutherfords model called?
The nuclear model
What did Niels Bohr discover?
That electrons are in energy levels around the nucleus
What is Bohrs model called?
The planetary model
What charge do protons have?
Positive
What charge do electrons have?
Negative
What charge do neutrons have?
Neutral/ no charge
What does a.m.u stand for?
Atomic mass unit
What determines an elements atomic number?
The amount of protons?
What is are electrons in the last shell of an atom called?
Valence electrons
What are ions?
The result of an atom gaining or losing electrons
What are isotopes?
Different versions of an elements atom with different numbers of neutrons, mass, and radioactivity.
What is atomic mass?
The average mass for that element
What is a mass number?
The amount of mass in that atom
What is ionic bonding?
When a metal gives its valence electrons to a non metal
What is covalent bonding?
When two metals share a valence shell and valence electrons
What do chemical formulas represent?
A chemical reaction
What side are reactants on in a chemical equation?
The left
What side are products on in a chemical equation?
Right
What do you use to balance a chemical equation?
Coefficients
What sides of the periodic table are metals and non metals on?
Metals are on the left and non metals are on the right
What are qualities of metals?
Metals are shiny, durable, and good conductors
What are qualities of non metals?
Non metals are brittle, dull and good insulators.
What are the vertical columns on the periodic table called?
Groups or families
How do you tell how reactive elements are?
By how close they are to the left and right edges, (excluding column 18) the closer the more reactive
What is the most reactive element?
Fluorine
What is the second most reactive element?
Oxygen
What are the horizontal rows on the periodic table called?
Periods
