Matter and Measurement

Classification

Heterogeneous Mixture CompoundMatter ElementPure Substance Homogeneous

Chemistry

Study of composition, structure, and properties of matter and of changes that occur in matter

What is matter? Anything that has _______ and takes up space

What is mass? Measure of the amount of _______ in a sample

This is different than weight. Weight includes mass and the force of gravity on that mass

Matter

Matter is composed of Pure substances Mixtures

Pure substanceAll the particles are the same and they cannot be broken down by _________ processes

Mixture Has more than one ____________ in it

AtomsAtoms

An atom is the smallest unit An atom is the smallest unit of an ________.of an ________.

ElementsElements

An element is composed of An element is composed of atoms that all have the same atoms that all have the same number of ______. number of ______.

Elements are pure substances.Elements are pure substances.

ElementsElements

In pictures we represent In pictures we represent different elements as different different elements as different shapes or sizes or colors. shapes or sizes or colors.

Chemical symbols

Elements have been given symbols to represent them in shorthand.

Some symbols are shortened forms of the element name: Carbon – C Oxygen – O Neon – Ne

Some symbols come from names in languages other than English. Sodium – Na Copper – Cu

Symbols are always 1-2 letters, capital first, then small

Elements

Listed in the periodic table

Must know1-31, 33-38, 40,

42, 46-48, 50-51, 53-57, 74, 78-80, 82-83, 86-87, 89, 92, and 94

CompoundsCompounds

A compound is composed of several A compound is composed of several types of elements bonded together. types of elements bonded together.

Compounds are pure substances.Compounds are pure substances.

MoleculesMolecules

A molecule is the smallest A molecule is the smallest unit of a _________.unit of a _________.

Composition

The composition of a sample tells what elements are in the sample The simplest ratio of those elements with respect

to each other.

Chemical formulas

A chemical formula tells which elements are in a compound, and the simplest ratios of the elements.

A subscript is used after an element if there is more than one atom of that type in a molecule. H2O = 2 hydrogen atoms with 1 oxygen atom.

Al2O3 = 2 aluminum atoms with 3 oxygen atoms.

Mixtures

Substance containing 2 or more pure substances mixed together

Classified as heterogeneous or homogeneous

Heterogeneous Mixture

Contains phasesInterface- area between two phases

Homogeneous Mixture

Same appearance throughout Classified as ___________

Suspensions, Colloids, and Solutions

Heterogeneous mixture Suspension

_______ particle size Particles suspended for a time but will settle out

Colloid _______ particle size Particles stay suspended

Homogeneous mixture Solution

_______ particles size Particles stay suspended

Solution

_______- thing being dissolved_______- thing doing dissolving

Physical vs Chemical

Properties- description of matter Physical- characteristic of matter displayed without a

chemical change Odor, color, density, etc…

Chemical-characteristic of matter displayed during a chemical change Reactivity

Changes- description of a change to matter Physical- change in matter that does not affect its

composition Phase change, dissolving, cutting or tearing, etc…..

Chemical- change in matter that does affect its composition Chemical rxn

Property Types

Extensive Property that is dependent on the amount of matter

present in a sample For example: _______________________

Intensive Property that is not dependent on the amount of

matter present in a sample For example: ________________________

Measuring Matter

Two Methods Qualitative- gives a ________________

For example: Sodium chloride is a white, crystalline structure.

Quantitative- gives a _______________ For example: Mass = 13.5 g

Measurement Tools

Length ______________

Mass ___________

Time _____________

Temperature ______________

Volume ____________________

Precision and Accuracy

Precision deals with how consistent a measurement is

Accuracy deals with correct a measurement is

Significant Figures

Rules apply only to _______________ Degree of uncertainty

Do not apply to Counted objects

For example- 6 sides in a hexagon or 20 books

Defined fractions and values For example- radius is

half of a diameter of a circle or 1000m is 1km

Determining Number of Sig Figs

All _________ digits are significantZeros

Significant if Caught between two significant figures (107) Found at the end of a number to the right of the decimal

point (2.00) Not significant if

Found to right of non-zero digits in a number without a decimal point (50)

Found to the left of the decimal point in a number less than 1 (0.5)

Found to the right of the decimal point in front of the non-zero digits (0.005)

Sig Figs in Calculations

Addition and Subtraction Answer should have the same number of places after

the decimal as the number with the least number of places after the decimal that is used in the problem

It is best to round after completing the calculation

Multiplication and Division Answer should have the same number of sig figs as

the number with the least number of sig figs used in the problem

It is best to round after completing the calculation

Scientific Notation

Method of expressing very large or small numbers

Steps1. Decimal is placed in the number so that that number is

greater than or equal to 1 but less than 10 (for example: 26653 becomes 2.6653)

2. Notation is added to reflect the number of places that the decimal moved and the direction that it moved in If decimal is moved 4 places to the left, a “x 104” will be

added to the number If decimal is moved 4 places to the right, a “x 10-4” will

be added to the number

SI Units

Modern version of metric systemSI Base Units

Length- __________ Mass- ___________ Time- ___________ Temperature- _________

although we will often use Celsius (◦C) K = °C + 273

Derived Unit Combine multiple base units

For Example: _____________

Metric System Prefixes

Tera (T) 1012

Giga (G) 109

Mega (M) 106

Kilo (k) 103

Hecto (h) 102

Deca (da or dk) 101

Deci (d) 10-1

Centi (c) 10-2

Milli (m) 10-3

Micro (µ) 10-6

Nano (n) 10-9

Pico (p) 10-12

Factor Labeling

Method used to convert numbers from one unit to another

Multiply (and divide) using conversion factors Factors need to equal 1 when divided

2.54 cm––––––– = 1 1 in.

1 in.––––––– = 1 2.54 cm