Exam 1 terms

Question 1

What are variables?

Answer 1

Variables are things or factors that can influence the outcome of an investigation

Question 2

What is a scientific model?

Answer 2

A model is a representation of an idea, and object or even a process or a system that is used to describe and explain something that cannot be experienced directly

Question 3

What is an ion?

Answer 3

When an atom loses or gains electrons. This will result in the atom having a positive or negative charge.

Question 4

What is an isotope?

Answer 4

Isotopes are atoms with the same number of protons but different number of neutrons. Therefore different mass.

Question 5

What is an element?

Answer 5

An element is a pure substance made up of one type of atom and cannot be broken down into simpler substances.

Question 6

What is a diatomic element?

Answer 6

Elements which naturally occur as molecules made up of two identical atoms chemically bonded together. Must be identical.

Question 7

What is diffusion?

Answer 7

The movement of particles from an area of high concentration to one of low concentration, until the particles are evenly distributed.

Question 8

What is a compound?

Answer 8

A chemical compound is a substance that consists of two or more different elements chemically bonded together in a fixed proportion

Question 9

What does IUPAC mean?

Answer 9

International Union of Pure and Applied Chemistry

Question 10

What is a binary compound?

Answer 10

A binary compound is one in which there are atoms from two different elements present

Question 11

What is valency?

Answer 11

Valency is the number of bonds an atom of a particular element can make when bonding with another atom

Question 12

What is the order of valency?

Answer 12

0,1,2, skip ten groups, 3,4,3,2,1,0

Question 13

What is a scientist

Answer 13

A person who wants to know more about the world.

Question 14

What do scientists use?

Answer 14

investigations, tests and experiments in order to answer questions, solve problems or explain different phenomena.

Question 15

What are the three types of variables?

Answer 15

Independent, dependent and fixed variables

Question 16

What is an atom?

Answer 16

All matter is made of tiny particles called atoms. Smallest part of an element that can exist on its own.

Question 17

What is a nucleon?

Answer 17

proton and neutrons together.

Question 18

What is the symbol for a proton, the charge and location?

Answer 18

P+, positive, nucleus

Question 19

What is the symbol for a neutron, the charge and location?

Answer 19

N°, neutral, nucleus

Question 20

What is the symbol for a electron, the charge and location?

Answer 20

e-, negative, orbiting around the nucleus

Question 21

What does the nucleus make up in the atom?

Answer 21

The volume

Question 22

Why are atoms always beau real?

Answer 22

Protons are equal to electrons therefore atoms are always neutral

Question 23

How many elements, groups and periods are on the periodic table?

Answer 23

118 elements, 18 groups and 7 periods

Question 24

What is the symbol for the atomic number? What does the number tell us?

Answer 24

The symbol is a z. Tells us the number of protons and electrons present in the nucleus of the atom.

Question 25

What is the symbol for the atomic mass? What does it tell us?

Answer 25

The symbol is A. It tells us the number it nucleons in he nucleus.

Question 26

What is the formula to find out the neutrons?

Answer 26

number of neutrons= = A - Z = number - number = number of neutrons

Question 27

How many electrons can the Bohr model hold in the first energy level? second energy level?

Answer 27

2 8 8 8

Question 28

What is the oder we follow when placing electrons?

Answer 28

Top, bottom, side, side, repeat

Question 29

What is group 1 called?

Answer 29

alkali metals

Question 30

what is the name of Group 2

Answer 30

Alkali earth metals

Question 31

What is the name of group 17?

Answer 31

halogens

Question 32

what is the name of group 18?

Answer 32

noble gases or inert gases

Question 33

another name for semi-metals?

Answer 33

metalloids

Question 34

what is electrical conductivity?

Answer 34

the ability for a substance to allow a charge to flow through it

Question 35

what is heat conductivity?

Answer 35

the ability of a substance to transfer heat.

Question 36

Metallic lustre or dullness

Answer 36

describes how shiny or dull a substance is

Question 37

Malleable

Answer 37

the ability of a substance to be hammered and shaped without breaking

Question 38

ductile

Answer 38

the ability of a substance to be drawn into think threads

Question 39

string or brittle

Answer 39

how easily a substance breaks

Question 40

Name the five characteristics of metals.

Answer 40

* Strong, malleable, and ductile * High melting and boiling points * Good conductors of electricity and heat * Mainly solids at room temperature ( mercury is an exception, and is a liquid at room temperature) * Becomes shiny when polished, therefore lustre

Question 41

Give the five characteristics of non-metals.

Answer 41

* Brittle (except diamond) * Low melting and boiling points (except diamond) * poor conductors of electricity and heat * solids, liquids and gases at room temperature * full looking (except diamond)

Question 42

Give the 7 diatomic elements

Answer 42

``` Have no fear of ice cold bear Hydrogen Nitrogen Fluorine Oxygen Iodine Chlorine Bromine ```

Question 43

What is an impure substance?

Answer 43

Result of a combination of two or more substance that have not reacted chemically. Mixtures may be separated by physical processes like filtration, evaporation and distillation.

Question 44

What two groups can mixtures be divided into?

Answer 44

Heterogeneous and homogenous

Question 45

What is heterogenous mixtures?

Answer 45

Components parts can be distinguished. | Eg. ice in soda, cereal in milk, oil mixed with water

Question 46

What is homogenous mixtures?

Answer 46

Component parts cannot be distinguished. | Eg. Tap water, atmospheric air, steel, salt water

Question 47

What is the solute, solvent and solution?

Answer 47

Solute is what is being dissolved. Solvent is what is doing the dissolving. Solution is the final product when it is all mixed together.

Question 48

What is a chemical formula?

Answer 48

a symbolic representation of a compound and gives the following information about a compound: • the name • the elements present • the ratio of the elements combined

Question 49

What is a metal + non metal called?

Answer 49

Ionic

Question 50

What is non metal + non metal called?

Answer 50

Molecule

Question 51

How do we determine the chemical formula for a binary compound?

Answer 51

We use the system called swop and drop

Question 52

How do we determine the chemical name for a binary compound?

Answer 52

It firstly depends whether it’s is ionic compound or molecule

Question 53

Rules for naming ionic compound

Answer 53

• Name of the first metal written first and the same • Name of the second element changes to end with ide Eg. Sodium chloride

Question 54

Rules for naming a molecule

Answer 54

* The second element ends with ide * Add prefixes to the name of the elements to specify the number of atoms of a particular element are present * mono is left out of the beginning of the first word. * but other prefixes have go on the first word

Question 55

Name the six prefixes

Answer 55

``` 1 - mono 2 - di 3 - tri 4 - tetra 5 - penta 6 - hexa ```

Question 56

What is a particle diagram?

Answer 56

A way of representing molecules and compounds. If they shapes are joined (touching) each other it means they have chemically bonded

Question 57

Gives the tips of the particle diagram

Answer 57

* Hydrogen is always drawn smaller | * if multiples atoms, write the name of the central atom first