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Flashcards in Definitions Deck (30):
1

Actual yield

The amount of product obtained

2

Theoretical yield

Maximum amount of product that could theoretically be obtained

3

Percentage yield

Actual yield described as % of theoretical yield

4

Rate or reaction

Speed at which a reaction takes place. Mesured by rate at which product is formed or reactants used.

5

Catalyst

Substance that speeds up a reaction without being changed or used up itself.

6

Element

Pure substance containing one type of atom

7

Compound

Substances containing two or more elements chemicaly combined

8

Mixture

Two or more substances mixed together but not chemicaly combined

9

Molecule

Group of atoms of one or more elements chemicaly combined with a finite number of atoms

10

Alloy

Other elements mixed with a metal to give it useful properties

11

Atom

Smallest particle of an element

12

Electron shell

Regions occupied by electrons around the nucleus

13

Electron structure

Show the number of electrons in each she'll 2,8,8

14

Periodic table

Shows elements in order of atomic number

15

Groups

Vertical columns of periodic table

16

Periods

horizontal rows of periodic table

17

Formula

Shows ratio / number of atoms of each element in a compound or molecule

18

Law of conservation of mass

Total mass of products equals total mass or reactants in any chemical reaction

19

Balanced chemical equation

Total number of atoms of each element are equal on either side of a chemical equation

20

Ore

Rock or mineral containing enough metal to make extraction economic

21

Phytomining

Extraction of metals from plant ash

22

Bioleaching

Extraction of metal from low grade ores using bacteria or fungi

23

Global warming

Gradual rising of temperature of the atmosphere

24

Global dimming

When polluting particles prevent a proportion of sunlight from penetrating the atmosphere

25

Greenhouse gas

Gas in the atmosphere which prevents reflected Ray's from the sun from leaving the atmosphere

26

Catalytic converter

A box on the exhaust containing platinum which helps convert nitrogen oxides to nitrogen and oxygen

27

Flu gas scrubber

Contains calcium hydroxide which reacts with sulphur dioxide in factory chimneys to prevent its release into the atmosphere

28

Alkanes

Hydrocarbons with general formula CnH2n+2

29

Viscosity

How easily a liquid can flow

30

Fraction

Contains a mixture of compounds with molecules of similar size and boiling point