Science structures n property

Atom

The basic building blocks of all matter in the universe

Element (Structure and Properties of Matter)

Pure substances made up of one type of atom.E.g, oxygen(O), gold(Au), Hydrogen(H)

Compound(Structure and Properties of Matter)

when 2 or more different elements bond together.E.g, water(H₂O), carbon dioxide(CO₂)

Molecule

2 or more atoms bonded together(doesn’t have to be different types of atoms)

Mixture(Structure and Properties of Matter)

2 or more substances that are physically combined but not chemically bonded.E.g, salads, salt and water.Can be serparated through physical methods

Homogeneous(Structure and Properties of Matter)

Mixture looks the same throughout.E.g, air, salt and water, juice.

Heterogeneous(Structure and Properties of Matter)

Different parts are easily seen.E.g, Salads, water with unmelted ice cubes, solids in liquids.

Filtration(Structure and Properties of Matter)

A method to separate mixtures through filtrating solids from liquids.Usually used for heterogeneous mixtures.

Evaporation(Structure and Properties of Matter)

A method to separate mixtures through evaporating liquids to get solid.

Magnetism(Structure and Properties of Matter)

Using magnets to attract magnetic materials

Centrifugation(Structure and Properties of Matter)

Spins mixtures to separate components, usually used on homogeneous mixtures.

Physical property(Structure and Properties of Matter)

a characteristic of a substance that can be observed or measured without changing the substance into something new.

Chemical property(Structure and Properties of Matter)

describes how a substance reacts and changes into a new substance.A chemical change forms something new.

Electron(Structure and Properties of Matter)

Negatively charged particles in an atom that orbits around the nucleus

Proton(Structure and Properties of Matter)

Positively charged particles in the inside of the atom’s nucleus, the amount of protons set the elements type.

Neutron(Structure and Properties of Matter)

Particles with no charge inside of the nucleus of an atom.

What determines the atomic number of a chemical(Structure and Properties of Matter)

The amount of protons.E.g, carbon’s atomic number is 6, therefore theres 6 protons in a carbon.

What determines the Atomic mass of a chemical(Structure and Properties of Matter)

The sum of protons and neutrons.Carbon’s atomic mass is 12.01, 6 from the protons and 6 from the neutrons

Periods/rows of a periodic table(Structure and Properties of Matter)

The 7 horizontal rows that tells you how many electron shells an electron has.E,g Indium(In) is in the 5th row, therefore it has 5 electron shells.(the two rows at the bottom of the periodic table are actually 6 and 7 rows, they’re split from the 6 and 7 as they were too long)

Groups/columns(Structure and Properties of Matter)

Elements in the same columns share similiar chemical properties because they have the same amount of valence electron(electrons in the outer most shell of a chemical)

Electron shell rule

The 2,8,8 rule for the first 20 elements of the periodic table.States that the electron shell 1, the layer closest to the nucleus can hold a max of 2 electrons.Shell 2 can hold a max of 8 electrons, shell 3 is also 8 and the rest go into shell 4.

Metal

An element that is usually shiny, conducts electricity and is malleable

Non metal

An element that is usuallu dull, brittle and a poor conductor

Metalloid

An element with properties of both metal and non metal

Reactivity

How easily an element reacts with other substances

Atomic radius

The distance from the atom’s nucleus to edge of the outermost electron shell

What does having more electron shells do to the atomic radius

Makes it larger in size as the shells take up space

What does having more protons do to the atomic radius

Makes it smaller because more protons means stronger inward pull on the electrons.

Electronegativity

How strongly an atom can attract and pull electrons towards itself when it is bonded to another atom.The more protons an atom has the higher the electronegativity is.The more electron shells there are, the less electronegativity an atom has due to the protons being further away from the other atom.

Ionisation energy

The amount of energy required for anatom to lose an electron, breaking the balance between the proton and electron balance(usually has equal amounts) and creating positively charged ion.More protons mean more pulling force on the electrons and therefore, harder to be taken away.More electron shells means lower ionisation(easier to lose electrons) because valence electrons are further from the nucleus.

Electron affinity

Readiness to accept electrons, breaking the balance between proton and electron and getting a negatively charged ion.Increases with more protons due to more pulling force for other electrons.Less electron shells means the other atom becomes further away and harder for their electron to be taken.

Metallic character

The exact opposite of ionzation; how willingly it loses electrons.If an atom has high ionization energy then it will always have a low metallic character and vice versa.

Valency

How many electrons an atom requires to fill out its outermost electron shell and become stable.E.g, oxygen(O) has 6 valence electrons in its outershell, therefore it has a low valency of 2 since it needs to more electrons to finish its outershell.

H (element)

Hydrogen

C(element)

Carbon

N(element)

Nitrogen

O(element)

Oxygen

Si(element)

Silicone

Fe(element)

Iron

Na(element)

Sodium

H_²O

Water

NaCl

Tablesalt

CO₂

Carbon Dioxide

C₆H₁₂O₆

Glucose

Oxygen gas

O₂

CO

Carbon monoxide