ATOMIC STRUCTURE AND THE PERIODIC TABLE

Question 1

Define atoms

Answer 1

smallest part of an element that can still be recognised as that element.

Question 2

Define elements

Answer 2

A substance made up of only one type of atom. An element cannot be broken down chemically into any simpler substances.

Question 3

Why are there symbols on the periodic table?

Answer 3

Other languages call the names of the elements different than other languages so symbols helps to communicate with other scientists + all nationalities can understand.

Question 4

Define period table

Answer 4

An arrangements of elements in the order of their atomic numbers, forming groups and periods.

Question 5

Define groups

Answer 5

Elements in the table that are arranged in columns.

Question 6

What do each group contain?

Answer 6

elements with similar chemical properties.

Question 7

Define molecule

Answer 7

grouping of two or more atoms bonded together

Question 8

What does each atom consists of?

Answer 8

tiny nucleus surrounded by electrons

Question 9

Define compounds

Answer 9

a substance made when two or more elements are chemically bonded together.

Question 10

What do chemical bonds hold?

Answer 10

Atoms tightly together in compounds.

Question 11

Define reactants

Answer 11

substances you start with

Question 12

define products

Answer 12

new substance made

Question 13

What do chemical reactions show?

Answer 13

shows the reactants and the products in a reaction

Question 14

What is the word equation for hydrogen gas?

Answer 14

hydrogen + oxygen –> water

Question 15

How does symbol equation help you?

Answer 15

lets you see how much of each substances are involved in a reaction

Question 16

What does the “equation is balanced” mean?

Answer 16

same number of each type of atom on both sides of the equation.

Question 17

Can atoms be created or destroyed in a chemical reaction?

Answer 17

NO!!!

Question 18

What is the law of conservation of mass?

Answer 18

the total mass of the products formed in a reaction = total mass of the reactants.

Question 19

Define state symbols

Answer 19

abbreviations used in balanced symbols equations to show if reactants and products are solid, liquid, gas or dissolved in water.

Question 20

Define aqueous solution

Answer 20

the mixture made by adding a soluble substance to water

Question 21

What is the rule in balancing a chemical equation?

Answer 21

NEVER change a chemical formula

Question 22

Define mixture

Answer 22

made up of two or more substances (elements or compounds) that are not chemically joined together

Question 23

What are the differences between mixtures and compounds?

Answer 23

COMPOUNDS –> have fixed positions

chemical reactions must be used to separate the elements in a compound

chemical bonds between the atoms of the different elements in the compound.

MIXTURES –> have no fixed positions

different elements or compounds in a mixture can be separated again more easily.

no chemical bonds between atoms of the different substances in a mixture

Question 24

How can mixtures be separated?

Answer 24

by physical processes

Question 25

What are the four physical processes the mixtures can be separated?

Answer 25

Filtration Crystallisation Distillation Chromatography

Question 26

How is filtration used?

Answer 26

It is used to separate substances that are insoluble in a particular solvent from those that are soluble in the solvent.

Question 27

How is crystallisation used?

Answer 27

separates a soluble solid from a solvent

Question 28

What can distillation separate?

Answer 28

mixtures of miscible liquids, such as ethanol and water

Question 29

Describe miscible

Answer 29

liquids that dissolve in each other, mixing completely

Question 30

Why is it difficult to get pure liquids from mixtures of liquids with similar boiling points by simple distillation?

Answer 30

vapour is given off from each liquid before they actually reach their boiling points

Question 31

What is a fractionating column?

Answer 31

a tall glass column filled with glass beads, fitted vertically on top of the flask being heated.

Question 32

What is the temperature in the fractionating column?

Answer 32

Highest at the bottom of the column, getting lower as the vapour rises up.

Question 33

What will happen to the substance with the higher boiling point?

Answer 33

will condense more reading on the cooler glass beads nearer the bottom of the column and drip back down into the flask beneath.

Question 34

What will happen to the substance with the lower melting point?

Answer 34

it will continue to rise and press over into the condenser, where it is cool enough to turn back into the liquid state and be collected.

Question 35

Define ethanol

Answer 35

a flammable liquid but is not flammable when mixed with an excess of water

Question 36

What is fractional distillation used to separate?

Answer 36

ethanol from a fermented mixture in the alcoholic spirits industry + in the use of ethanol as a biofuel.

Question 37

Define biofuel?

Answer 37

fuel made from animal or plant products

Question 38

How does paper chromatography separate?

Answer 38

separates substances from mixtures into solution

Question 39

What did John Dalton suggest?

Answer 39

the substances were madce up of atoms that differed from others in their mass

Question 40

What did Dalton believe?

Answer 40

atoms could not be divided or split.

Question 41

What did Dalton suggest about chemical reactions?

Answer 41

suggested that the atoms re-arranged themselves + combined with other atoms in new ways

Question 42

What did Rutherdord suggest?

Answer 42

that the Thomoson's atomic model was not possible positive charge must be concentrated at a tiny sspot ion the centre of the atom

Question 43

What was proposed about the electrons?

Answer 43

that it must be orbiting around the nucleus, which contains very dense positively charged protons.

Question 44

Why was it difficult to detect the neutrons in experiments?

Answer 44

have no charge

Question 45

What does the nucleus contain?

Answer 45

2 types of sub-atomic particles, called protons + neutrons. The third type of sub-atomaic particle which orbits the nucleus

Question 46

What charge does proton have?

Answer 46

positive

Question 47

What charge does neutron have?

Answer 47

no charge NEUTRAL

Question 48

What charge does the nucleus have?

Answer 48

overall positive charge

Question 49

What charge does the electrons orbiting the nucleus have?

Answer 49

negative charge

Question 50

What is the relative charge on proton?

Answer 50

+1

Question 51

What is the relative charge of an electron?

Answer 51

-1

Question 52

What is the mass of an atom concentrated on?

Answer 52

nucleus

Question 53

What mass do proton and neutron have?

Answer 53

same mass

Question 54

why is electron mass ignored when working out the relative mass of atoms?

Answer 54

because they are light

Question 55

define atomic number

Answer 55

number of protons in each atom of an element

Question 56

define mass number

Answer 56

number of protons + neutrons in the nucleus of an atom

Question 57

What does atom have the equal number of?

Answer 57

protons + electrons

Question 58

How do you find out the number of neutrons?

Answer 58

mass number - atomic number

Question 59

Why are atoms neutral?

Answer 59

equal number of protons + electrons

Question 60

What will happen if an atom gains one or more electrons?

Answer 60

gains an overall change because it has more electrons than protons. --\> atom become a negative ion

Question 61

What if a atom loses one or more electron?

Answer 61

becomes a positive ion because it has more protons than electroms

Question 62

Define ion

Answer 62

charged atom (for group of atoms)

Question 63

Why can you not see the atom?

Answer 63

because each individual atom is incredibly small

Question 64

Define isotopes

Answer 64

atoms of the same elements with different numbers of neutrons

Question 65

What does isotopes always have?

Answer 65

same atomic number but different mass number

Question 66

What does extra neutrons do to the nucleus?

Answer 66

sometimes, its unstable + radioactive

Question 67

Whta is an energy level (shell)?

Answer 67

an area in atom, around its nucleus, where electrons are found

Question 68

Define electronic structure

Answer 68

a set of numbers to show the arrangement of electrons in their shells

Question 69

What are the outer electron?

Answer 69

atoms that have the same number of electrons in the hgihest energy level

Question 70

Why are elements in group 0 called the noble gasses?

Answer 70

very unreactive elements