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Flashcards in Chapter 4 Deck (31):
1

Unit of measurement for mass of an atom

1 amu = 1.66 x 10^-24

2

Where can you find the atomic weight

number on periodic table

3

Whats the amu of an element on the periodic table?

the number listed on periodic table

4

Whats the number for a mole of atoms?

6.022 x 10^23

5

Another name for a 'mole'

Avogadro's number

6

Definition of a mole?

Counting unit

7

How to convert grams to moles?

Divide grams by moler mass

8

Formula Unit

the smallest collection of atoms that provide two important pieces of information
-Identity of the atoms
-The relative # of each type of atom

9

Hydrate?

compounds containing one or more water molecules as an integral part of their structure

10

Formula weight

sum of the atomic weights of all atoms in the compound as represented by its correct formula (expressed in amu)

11

How to find amu of a compound

add amu of all elements in compound up

12

what is the atomic weight also known as?

AMU

13

Formula weight is also known as?

Molar Mass

14

What is the molar mass of (NH4)sub3POsub4

149.10g/mol

15

What is the 'molar mass'?

It's the mass in grams of 1 mole of atoms

16

What is molar mass of carbon?

12.01 g/mol C

17

Chemical Equation?

shorthand notation of a chemical reaction

18

Reactants

(starting Materials) - the substances that undergo change in the reaction

19

Products

Substances produced by the reaction

20

5 Features of a Chemical Equation?

1. Identity of products and reactants must be specified using chemical symbols
2. Reactants are written to the left of the reaction arrow and products are written to the right
3. Physical states of reactants and products may be shown in parentheses
4. Symbol ^ over the reaction arrow means that energy is necessary for the reaction to occur

21

Evidence of a reaction occurring?

- Release of a gas
- Formation of a solid (precipitate)
- Heat is produced or absorbed
- Color changes

22

Subtle indications of a reaction?

- Heat or Light is absorbed or emitted
- Changes in the way the substances behave in an electrical or magnetic field before and after reaction
- Changes in electrical properties

23

Patterns of chemical reactions

- combination
- decomposition
- single-replacement
- double-replacement

24

Types of combination Reactions

1. Combination of a metal and a nonmetal to form a salt
2. Combination of hydrogen and chlorine molecules to produce hydrogen chloride
3. Formation of water from hydrogen and oxygen molecules
4. Reaction of magnesium oxide and carbon dioxide to produce magnesium carbonate

25

Types of decomposition reactions?

1. Heating calcium carbonate to produce calcium oxide and carbon dioxide
2. Removal of water from a hydrated material

26

Law of conservation of Mass?

matter cannot be either gained or lost in the process of a chemical reaction

27

What must the total mass of the products equal?

Total mass of the reactants

28

Precipitation Reactions

- Chemical change in a solution that results in one or more insoluble products- To predict if a precipitation reaction can occur it is helpful to know the suitabilities of ionic compounds

29

Theoretical yield

maximum amount of product that can be produced-pencil and paper yield

30

Actual yield

amount produced when the reaction is performed -laboratory yield

31

% yield formula?

%yield = actual yield / theoretical yield x 100%