C1: Atomic Structure and the Periodic Table

What is an atom?

The smallest unit of matter made up of protons, neutrons and electrons

What is the radius of an atom?

1 x 10^-10 metres

What is the radius of the nucleus of an atom?

1 x 10^-14 metres

What are the 3 sub atomic particles of an atom?

Protons

Neutrons

Electrons

Where are the protons and neutrons located in an atom?

In the nucleus

Does the nucleus have a positive or negative charge?

Positive

Why does the nucleus have a positive charge?

The protons are positive

Where is most of the mass in an atom concentrated?

The nucleus

What is the relative mass and charge of a proton?

Mass = 1

Charge = +1

Where are electrons located in an atom?

On shells orbiting the nucleus

What is the relative mass and charge of a nuetron?

Mass = 1

Charge = 0

What is the relative mass and charge of an electron?

Mass = very small

Charge = -1

T or F: neutral atoms have the same number of protons and electrons?

T

What does the atomic number tell you?

The number of protons (that is the same as the number of electrons)

What does the mass number tell you?

The total number of protons and neutrons

The number of which sub atomic particle determines which element the atom is?

Protons

Define element.

A substance made up of only 1 type of atom

What is an isotope?

An atom of the same element with the same number of protons but a different number of neutrons

What is the formula to calculate relative atomic mass?

Ar = sum of (isotope abundance x isotope mass number) / sum of abundances of all the isotopes

Define compound.

A substance made up of 2 or more different elements that are chemically bonded together

What is an ion?

A charged particle

What is the chemical formula for ammonia?

NH3

What is the chemical formula for methane?

CH4

What is the chemical formula for carbon MONoxide?

CO

What is the chemical formula for sulfur dioxide?

SO2

What is the chemical formula for ethanol?

C2H5OH

What is the chemical formula for glucose?

C6H12O6

Which side of a reaction equation are reactants found on?

Left

Which side of a reaction equation are products found on?

Right

Define mixture.

A substance made up of 2 or more elements or compounds not chemically bonded together

What are the 3 main gases found in air?

Nitrogen

Oxygen

Argon

What can paper chromatography be used to separate?

Different dyes in an ink

Why does the start line in paper chromatography have to be drawn in pencil?

Pencil is insoluble so it wont dissolve when you put it into the water

How do the dyes/inks move up the paper in paper chromatography?

The solvent (water) carries the ink up the paper

How is a chromatogram formed?

The different dyes will separate out as they move up the paper at different rates, forming a pattern of spots where the dyes end

What does filtration separate?

Insoluble solids from liquids

What does evaporation separate?

Soluble solids from liquids

What is the name of the vessel used to heat the solution in evaporation?

An evaporating basin

What does crystallisation separate?

Soluble solids and liquids

What is "the point of crystallisation"?

The point at which crystals start to form

What are the 2 types of distillation?

Simple and fractional

What does simple distillation separate?

A liquid from a solution

What 2 changes of state are involved in simple distillation?

Evaporating and condensing

What is 1 disadvantage of simple distillaition?

It can only be used to separate liquids with very different boiling points

In what order are the liquids separated in fractional distillation?

From lowest boiling point to highest boiling point

Who first described atoms as solid spheres?

John Dalton

Who proposed the plum pudding model?

JJ Thomsom

In what year was the plum pudding model proposed?

1897

What did the plum pudding model show?

An atom as a ball of positive charge with negative electrons stuck to it

Who conducted the alpha particle scattering experiment?

Ernest Rutherford

In what year did Rutherford conduct his experiment?

1909

What type of foil did Rutherford fire the alpha particles at in his experiment?

Gold

What happened to the alpha particles when they were fired in Rutherford's Experiment?

Most went straight through the gold foil but some were deflected

What did Rutherford discover from his experiment?

Atoms have a positively charged nucleus where most of the mass is concentrated

Who came up with the idea that electrons orbit the nucleus on shells?

Niels Bohr

What was the name of Bohr's atomic model?

Nuclear Model

Who proved the existence of neutrons?

James Chadwick

In what order were the subatomic particles discovered?

Electrons

Protons

Neutrons

How many electrons are allowed in the 1st shell?

2

How many electrons are allowed in the 2nd and 3rd shell?

8

How were elements ordered in early periodic tables?

By atomic weight

In what year did Mendeleev create his periodic table?

1869

How did Mendeleev order the elements differently to older periodic tables?

He ordered them by atomic weight but also took into account their properties

Why did Mendeleev leave gaps in his periodic table?

For undiscovered elements

How are elements arranged in the modern periodic table?

Increasing atomic number

What side of the periodic table are metals found on?

Left

What side of the periodic table are non-metals found on?

Right

What are columns called on the periodic table?

Groups

What does group number tell us?

Number of electrons on the outermost shell

What are the rows called on the periodic table?

Periods

What does period number tell us?

Number of electron shells

What ions do metals form?

Positive

What ions do non-metals form?

Negative

What are 4 physical properties of metals?

Strong

Malleable

Good conductors

High melting and boiling points

Where are transition metals found in the periodic table?

Middle - between group 2 and 3

What are 3 special properties of TRANSITION metals?

They can have more than one ion

They are often coloured

They are good catalysts

What are group 1 metals called?

Alkali metals

What are the 6 alkali metals?

Lithium

Sodium

Potassium

Rubidium

Caesium

Francium

What are 2 physical properties of alkali metals?

They are soft and have low density

Why do all the alkali metals have similar chemical properties?

They all have 1 electron on the outer shell

Give 3 trends as you go down group 1.

Increasing reactivity

Lower melting and boiling points

Higher relative atomic mass

What is formed when group 1 metals are placed in water?

Hydrogen gas and metal hydroxides

What is produced when group 1 metals are heated in chlorine gas?

White metal chloride salts

What is formed when group 1 metals react with oxygen?

A metal oxide

T or F: transition metals are more reactive than group 1 metals.

F - group 1 metals are more reactive than transition metals

What are group 7 elements called?

Halogens

What are the 4 halogens you need to know?

Flourine

Chlorine

Bromine

Iodine

Give 3 trends as you go down group 7.

The elements get less reactive

They have higher melting and boiling points

They have higher relative atomic masses

Why do halogens react in similar ways?

They all have 7 electrons in the outer shell

What are halogen ions called?

Halides

T or F: more reactive halogens can displace less reactive ones.

T

What are the group 0 elements called?

Noble gases

What word can be used to describe the noble gases?

Inert