Atoms, Elements, Compounds & Mixtures Flashcards

1
Q

What is an atom?

A

Atoms are tiny, tiny particles.

An atom is the smallest part of an element that can exist.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define Dalton’s model on atoms

A

Dalton’s model on atoms

  • All matter is made up of atoms
  • There are different types of atoms
  • Each element contains a different type
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is an element?

A

Element is a substance that contains only one type of atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Give examples for elements

A
  • Oxygen
  • Nitrogen
  • Gold
  • Silver
  • Copper
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a compound?

A

Compounds form when different atoms join together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a molecule?

A

Molecules are when two or more atoms are chemically joined together

Molecules can be

  • element - same type of atoms joined together - O2
  • compound - different types of atoms joined together - CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between a compound and mixture?

A

In a compound elements are chemically joined together.

In a mixture elements are not chemically joined together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a mixture?

A

A mixture contains two or more substances not chemically joined together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a pure substance?

A

A pure substance is made up of only one type of element or one type of compoud.

It can’t be separated into anything simpler witout a chemical reaction e,g: water H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the difference between an element, a compound and a mixture?

A

An element has only one type of atom.

A compound has more than one type of atom, chemically joined.

A mixture has more than one type of atom or compound, not chemically joined.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a physical change?

A

Physical Changes

  • Physical changes are changes in appearance
  • A new substance is not created e.g. broken glass
  • Chemical bonds are not broken or formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How many elements there?

A

There are 92 elements.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Is water a compound? Explain your answer.

A

Water is a compound.

Two elements- hydrogen and oxygen are chemically joined together in water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define catalyst

A

Chemists use catalysts to speed up slow reactions if they want to make a product more quickly.

A catalyst is not used up in a reaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Salt is an element or compound?

A

Salt is a compound - NaCl

Salt contains two elements - sodium and chlorine.

Salt chemical name is sodium chloride.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the properties of sodium, chlorine and sodium chloride.

A

Sodium is a shiny metal. It fizzes in water.

Chlorine is smelly green poisonous gas.

Sodium chloride is salt and used in food all the time.

17
Q

State the number and type of atoms that make up one carbon dioxide molecule.

A

Carbon - 1 atom

Oxygen - 2 atoms

18
Q

Carbon dioxide and carbon monoxide are gases.

Which gas is poisonous?

A

Carbon monoxide

19
Q

Define chemical formula

A

A chemical formula shows the ratio of atoms of each element in the compound

20
Q

What is a chemical reaction?

A

A chemical reaction is a change in which atoms are rearranged to create a new substance.

21
Q

Give examples of two types of physical change

A

Physical changes

  1. Dissolving
  2. Changes of state
22
Q

State three examples of useful products made in chemical reactions

A
  1. Medicines such as paracetamol
  2. Fabric such as polyester
  3. Building materials such as cement
23
Q

Chemical reactions also transfer …………

Why is this useful?

A

Chemical reactions also transfer energy.

  1. Burning petrol makes vehicles go
  2. Burning coal heats water to produce steam to generate electricity
24
Q

Name two chemical reactions which are not useful

A
  1. Iron rusting is a chemical reaction.

It damages cars, boats and bridges.

  1. Chemical reactions make food rot.
25
Q

The first version of the Periodic Table was put together by the scientist ……

A

Scientist Mendeleev

26
Q

What is a periodic table?

A

The periodic table lists the elements.

27
Q

What are groups in a periodic table?

A

In the Periodic Table, elements with similar proerties are grouped together in vertical columns.

28
Q

What are chemical symbols?

A

Every element is represented by a chemical symbol.

29
Q

Give the chemical symbol for the following elements:

  1. Carbon
  2. Nitrogen
  3. Nickel
  4. Chlorine
  5. Gold
  6. Iron
  7. Tungsten
  8. Silver
  9. Oxygen
  10. Helium
A

Chemical symbols

Carbon C

Nitrogen N

Nickel Ni

Chlorine Cl

Gold Au

Iron Fe

Tungsten W

Silver Ag

Oxygen O

Helium He

30
Q

Explain the properties of platinum

A

Platinum is a shiny metal.

Platinum is not damaged by air or water.

It is easy to make platinum into different shapes.

Platinum is rare and expensive.

31
Q

Give four uses of platinum

A
  1. Jewellery
  2. A computer disk which stors data on a computer
  3. A heart pacemaker which helps the heart to beat regularly
  4. A catalyst converter for cars which changes harmful car exhaust gases into less harmful ones
32
Q

In a Periodic Table which groups are fairly reactive?

A

In a Periodic Table Groups 1, 2 and 7 are fairly reactive.

33
Q

What is the name for the horixontal rows in the Periodic Table?

A

The horizontal rows in a Periodic Table are called Periods

34
Q

Explain properties of Groups 1, 2 and 7

A

Groups 1, 2 and 7 are reactive, dead keen to combine

35
Q
A
36
Q

Explain properties of Group 0

A

Group 0 are noble gases; extremely unreactive

37
Q

Explain properties of Group 1 elements

A

Group 1 elements are soft, shiny metals which react in a similar way with water.

Group 1 elements are more reactive as you go down the group

38
Q

Explain properties of Group 7

A

Group 7 elements are non-metals

They get less reactive as you go down the group

39
Q

In a Periodic Table which group is extremely unreactive?

A

Group 0, Noble gases are extremely unreactive.