atomic structure

How many elements are on the periodic table?

118

what is an element made up of?

one type of atom

what is atoms represented by?

chemical symbols

what is the chemical symbol for the following atoms: sodium, calcium and potassium

Sodium (Na), Calcium (Ca), and Potassium (K) are represented by their respective chemical symbols.

what is the name of the column that elements are arranged to in the periodic table?

groups

what do atoms have?

nucleus, protons, neutrons, electrons

what is a compound?

2 or more elements chemically combined

what do chemical equations show?

the reactants and products of a reaction

reactants

A starting material in a chemical reaction

products

Ending materials in a chemical reaction.

what does symbol equation show

numbers and types of atoms in reactants and products

in a chemical reaction do atoms change?

atoms are not created or destroyed so the atom stays the same before and after the reaction

what are balanced equations

an equation is balanced when there are equal numbers of atoms of each element on both sides of the arrow (use multipliers to ensure its balanced)

what are the three state symbols?

solid, liquid and gas

aqueous solution

a solution in which water is the solvent

conservation of mass

the principle stating that matter is not created or destroyed during a chemical reaction

example of conservation of mass?

if melting an ice cube (solid) into water (liquid) the total mass will stay the same because it isn't created or destroyed

what is a mixture?

A combination of two or more substances that are not chemically combined

what are mixtures separated by?

physical processes

what is filtration?

when you separate an insoluble substance in a solvent to a soluble in a solvent

example of filtration

sand can be separated from salt solution using filtration

Crystallization

separates a soluble substance from a solvent

example of crystallization

making rock candy from a sugar solution

distillation

separates a solvent from soluble solids dissolved in solvent

insoluble

incapable of being dissolved

soluble

capable of being dissolved

solvent

A liquid substance capable of dissolving other substances

Fractional distillation

Method to separate a liquid mixture into its individual components e.g. ethanol and water

miscible liquids

Liquids that can mix together.

how to aid separation?

add a fractionating column to the distillation apparatus

what can fractional distillation do to ethanol?

it can separate ethanol from a fermented mixture in alcohol drink industries

in fractional distillation which liquid is collected first?

the lowest boiling point

chromatography

A technique that is used to separate the components of a mixture.

example of when chromatography is used

separating food colouring

Daltons theory 1800s

all matter is made up of individual particles called atoms, which cannot be divided

Thomson

discovered the electron, plum pudding model

plum pudding model

electrons were randomly distributed within a positively charged cloud

Geiger & Marsden experiment

A beam of alpha particles was aimed at a sheet of thin gold foil

what happened after shooting alpha particles at the golden foil?

there were tiny spots of positive charge in the centre of the atom

what did Rutherford create

Nuclear model

Nuclear model

Model of the atom with a nucleus containing protons and neutrons and with electrons in the space outside the nucleus

Bohr's Theory

electrons move in a circular orbit around the nucleus, the electron were distanced from the nucleus

Chadwick's Discovery

neutron

what does nucleus at the centre contain

two types of sub-atomic atoms: neutrons and protons

protons

Positively charged particles +1

neutrons

the particles of the nucleus that have no charge 0

electrons

Negatively charged particles -1

number of protons

atomic number

number of neutrons

mass number - atomic number

number of electrons

same as the number of protons

ions

Charged atoms

what happens if atoms gain electrons

They form negative ions

what happens if atoms lose electrons

They form positive ions

isotope

An atom with the same number of protons and a different number of neutrons

example of an isotope

Carbon-12, Carbon-13, Carbon-14

electronic structures

Arrangement of electrons in an atom's energy levels.

where do electron occupy the lowest energy level

the shell closest to the nucleus

how many electrons can the first shell hold

2 electrons

How many electrons can the second energy level hold?

8 electrons

example of a electronic structure

sodium has 11 electron so sodium's electronic structure is 2,8,1

how do you find the number of electron in the outer shell

look at their groups and what number they are

how many electrons are in the highest energy level of group 2 elements

2 electrons

what are noble gases

unreactive elements that have a very stable arrangement of electrons.

three elements that are noble gases

helium, argon, krypton