Chemistry y9

Arrangement of a solid

Regular, fixed

Arrangement of a liquid

random, touching

Arrangement of a gas

Far apart, random, sparse

Movement of a solid

vibrate in place

Movement of a liquid

Flowing, random

Movement of a gas

Free, random

Energy of a solid

Least energy

Energy of a liquid

medium energy

Energy of a gas

Highest energy

What kind of energy does a gas have

Kinetic

What is a solid to a gas called

sublimation

What is a gas to a solid called

deposition

On a graph that shows the change of state what does a straight line mean

Change of state

Element

A simple substance made of only one type of atom

Compound

More than one type of atom chemically bonded

Pure

One type of element of compound: same in all parts of the substance

Mixture

Two or mire different substances not chemically bonded (physically bonded)

Solubility

A measure of how much solute can dissolve in a given solvent at a given temperature

Crystallisation

To separate a solute from a solution

Chromatography

Separates mixtures made of soluble substances

Mobile phase

Solvent

Stationary phase

chromatography paper

Rf value \=

Distance by solute / distance by solvent

What do you round the Rf to

2 d.p.

What does simple distillation do

Separates a solvent from a solution

What do anti

bumping granules do?

What does distillate mean

Pure water

What is a condenser

Tube surrounded by cold water

What does fractional distillation do

Separates liquids with similar boiling points

Where should the dots of ink not be in ink distillation

In the water

Why should the dots of ink in ink distillation not be in the water

Because they'll dissolve, not spread

What does screening do

To remove large objects

What does sedementation do

Solids sink and are left behind

What does coagulation do

Alum added to clump dirt

What does filtration do

Very small particles are removed

What does pH and chlorination do

pH check and chlorination to kill bacteria and viruses

What does distribution do

Water is stored for distribution

Order of these:

Coagulation

Distribution

Filtration

Ph and chlorination

Screening

Sedimentation

Screening

Sedimentation

Coagulation

Filtration

Ph and coagulation

Distribution

Charge of a proton

\+

Charge of an electron

\-

Charge of a neutron

neutral

Charge of an atom

neutral

Relative mass of a proton

1

Relative mass of an electron

1/1840

Relative mass of a neutron

1

What did dalton's theory state (4)

Atoms are the smallest part of a substance that can exist

atoms do not carry an overall charge

Atoms cannot be created or destroyed

atoms are the same in an element

How do you find out the relative atomic mass from the periodic table

Top number

What is the atomic number

Number of electrons/protons

How to find the relative formula mass (Mr) for a compound

Add all relative atomic masses

Isotope

Atoms of the same element with the same number of protons but a different number of neutrons

Charge of an isotope

A positive or negative charge

What does Ar stand for?

Relative atomic mass

Equation for relative atomic mass (Ar) (isotopes)

((isotope x %) + (isotope x %)) /100

What did Mendeleev do to the periodic table (3)

Ordered atoms in order of atomic weight

groups with similar properties

gaps for undiscovered elements

How do we order the periodic table now

Increasing atomic number

Rows are called ...

periods

Columns are called ...

Groups

Periods are ...

rows

Groups are ...

columns

What does the periods show

Number of electron shells

What does the groups show

Number of electrons in the outer shell

What is group 1 of the periodic table

alkali metals

What is group 2 of the periodic table

alkaline earth metals

What is group 3

12 of the periodic table

What is group 7 (17) of the periodic table

Halogens

What is group 8 (18) of the periodic table

Noble gases

In electron configuration ... up to ...

2.8.8.8 up to calcium

Ion

An atom for group of atoms with a positive or negative charge

What are positive ions called

cations

What are negative ions called

anions

What does inurt mean

Unreactive

Do metals lose or gain electrons when becoming ions

Lose

Do non

metals lose or gain electrons when becoming ions

Ionic bonding

The electrostatic attraction between oppositely charged ions

3 steps for ionic bonding

Draw elements

show electronic transfer

draw ions

Ammonuim sulfate is

NH4 (+1) SO4 (

2)

Ionic bond

Electrostatic charge between oppositely chargedions

What is the structure of an ionic lattice (3)

Many bonds

Crystalline structure

Alternating positive and negative

Covalent bond

A shared pair of electrons

What kind of bonds do simple covalent molecules have

Weak intermolecular forces

Why do simple covalent molecules have low m.p./b.p.

The forces require little energy to be overcome

Metallic bond

An electrostatic attraction between positive ions and a sea of delocalised electrons

properties of covalent molecules (2)

No delocalised electrons

Not conductor of electricity

Properties of metals

High melting points

Malleable

Strong

Ductile

Why do metallic structures have high m.p./b.p.

Large amount of energy to overcome the bonds

In metals the layers are able to ... .... each other while being held by the ... ...

Slide past, delocalised electrons

Conservation of mass (in a closed system)

The total mass of reactants is equal to the total mass of the products

Experiment with magnesium oxide and the conservation of mass

1. Magnesium in the crucible and put it on the balance
2. Put it on the clay triangle and heat strongly for several minutes
3. Lift the lid periodically to let the oxygen in
4. Let cool, once the magnesium stops glowing

Isotopes are atoms of the same elements with the same number of ......

Protons and a different number of neutrons

What are the 3 things that may happen when testing the conservation of mass

No change in mass

Mass increases because it took from the air

Mass decreases because gas escapes into the air

What is avogadro's constant/ 1 mole

6.02 x 10^23

What does the molecular formulae represent

The actual number of atoms of each element in one molecule