Chemistry topic 1

Who proposed the concept of atoms as invisible particles

Who proposed the concept of atoms as invisible particles

Democritus

What was Robert Boyle known for in atomic theory

Gases act according to laws

What is John Dalton atomic theory

Matter is made of invisible atoms

Atoms of the same element are identical

Atoms combine in simple ratios to form compounds

What model did JJ Thomson propose for the atom and what is it

The plum pudding model where electrons are embedded in a positively charged pudding and electrons are negatively charged subatomic particle

What did Ernest Rutherford discover

The nuclear model where electrons orbit the dense positively charged nucleus

Who discovered the neutron

James Chadwick

What did Niels Bohr propose in 1913 about electron

Electrons orbit the nucleus in fixed paths or energy levels

What are the physical properties of metals

Shinny

Malleable

Good conductors of heat and electricity

High melting and boiling points

Dense

Physical properties of non metals

Dull

Brittle

Poor conductors of heat and electricity

Low melting and boiling points

What is an alloy

A mixture of a metal with one or more elements

What charge does a metal and non metal have

Metal has a positive charge

Non metal has a negative charge

What is an atom

Unit of matter composed of a nucleus and electrons orbiting the nucleus

What particles make up an atom

Protons

Neutrons

Electrons

What charge does a proton neutron and electron have

Proton has +1

Neutron has 0

Electron has -1

What is atommic number

The number of protons in a nucleus of an atom

What is an isotope

Atoms of the same element that have the same number of protons but different amount of neutrons

What is an ion

Atom that has gained or lost electrons

What is electronic structure

Arrangement of electrons in an atom

How many can each shell hold

First shell 2 electrons

Second shell 8 electrons

Third shell 8 electrons

What is the outer shell

The furthest she’ll from the nucleus

What is filtration

Separating solids from liquids or gases using a filter

What is crystallisation

Purify a solid from a solution by allowing the dissolved substance to form crystals

What is the process of filtration

• Pour the mixture into the filter paper and funnel the liquid passes through while the solid is trapped in the filter

What is distillation

Separation of mixtures based on different boiling points

What are the steps in simple distillation

Heat the liquid mixture to vaporise the component with the lower boiling point

The vapour rises and is cooled in a condenser tiring back into liquid

The purified liquid is collected in a separate container

What are the steps of fractional distillation

Heat the liquid mixture the component with the lowest boiling point will vaporise

As it passes through the condenser it will turn back to liquid

If another liquid evaporates it will condense back because of the fractional column

Repeat the first two steps until all of the liquids are separated

What are alkali metals

Elements that are in group 1

What are the properties of alkali metals

Soft

Low melting points

Low density

Shinny

What happens as you go down the group

Reactivity increases

Boiling and melting point decreases

How alkali metal reacts with water

Vigorously with water producing hydrogen gas

What is a halogen

An element in group 7

What is the trend when you go down group 7

Reactivity decreases

Boiling and melting point increases

Are halogens diatomic or monoatomic

Diatomic

What is an displacement reactions

When a more reactive atom or substance displaces a less reactive atom or substance

what are noble gases

Group 0 elements

Are noble gases reactive

No they are stable

What physical properties do noble gases have

Boiling and melting point increase as you go down the group

Colourless

Non flammable

Odorless

In the early 1800s how were elements arranged in the periodic table

Atomic weight

How did Mendeleev arrange the elements in his periodic table

Grouped the elements with similar properties into columns and increasing atomic mass

Why did Mendeleev leave gaps in the periodic table

He predicted the properties and atomic masses of undiscovered elements

How did the discovery of isotopes help validate Mendeleev periodic table

Some isotopes had different masses but same chemical properties so he was correct in putting them in groups with other elements that had same chemical properties

What does the group number tell you about the atoms of an element

The number of electrons on the outer shell

What does the period tell you about the atoms of an element

The number of shells an atom has

What is an element

Pure substance consisting of only one type of atom characterised by its number of protons