Chem I Exam 1

Theory

is an explanation and explains why or how.

Accuracy

how close are you to the right answer.

Extrinsic Properties

depends on how much of the substance there is (mass, volume)

Microscopic

________- at the level of atoms and molecules.

Methane

a major component of natural gas.

Ions

charged atom or molecule made up of one or more molecules.

Compounds

can be separated chemically.

Neutral atom

the number of electrons equals the number of protons.

Protons

positively charged.

Recall

________- number of protons defines the identity of an element.

Chemical

________- different substances present the same or different physical forms (ex rust)

Macroscopic

big picture (what I can see or hear)

Hypothesis

________- is a scientific guess.

Isotopes

the same number of protons but different neutrons.

Isomers

________- different chemical structures but the same formula.

Plasma

a material made up of stars.

Physical State of Matter

________- solid, liquid, gas, plasma.

Element

composed of extremely small particles called "atom.

Compound

substances composed of two or more elements.

Law

is a measured relationship between two variables

hypothesis

is a scientific guess

Theory

is an explanation and explains why or how

Purpose

state the problem

Research

find out about the topic

Experiment

determine the experiment

Macroscopic

big picture (what I can see or hear)

Microscopic

at the level of atoms and molecules

Physical State of Matter

solid, liquid, gas, plasma

Plasma

a material made up of stars

Mixtures

can be separated physically

Compounds

can be separated chemically

Physical Change

same substance presents a different physical setting

Chemical

different substances present the same or different physical forms (ex rust)

Extrinsic Properties

depends on how much of the substance there is (mass, volume)

Intrinsic

depends only on what the substance is (ex

Density

d=m/v

Length

meter (m)

Mass

kilogram (kg)

Time

second (s)

Amount of substance

mole (mol)

Temperature

Kelvin (K)

Giga

10^9

Mega

10^6

Kilo

10^3

Centi

10^-2

Milli

10^-3

Micro

10 ^-6

Nano

10^-9

Pico

10^-12

Accuracy

how close are you to the right answer

Precision

based on the scatter (or same results)

To calculate accuracy

take the average

To calculate precision

do the standard deviation

Element

composed of extremely small particles called "atom"

Compound

substances composed of two or more elements

Law of definite proportions

different samples of the same compound contain elements in the same proportions by mass

Law of multiple proportions

if elements combine to form more than one compound of masses of one element that combine with a fixed mass of the other, will always be a small whole number ratio

A (alpha)

positively charged and are heavier than beta

Y (gamma)

does not have a charge

B (beta)

negatively charged

Plum pudding model of the Atom

1904 first idea for what an atom looks like

Electrons

negatively charged (-1.602 x 10^-19 C)

Protons

positively charged

Neutron

neutral charge

Atomic number

number of protons uniquely identifies the element

Mass number

number of protons plus neutrons

Neutral atom

the number of electrons equals the number of protons

Period

rows

Groups

columns

Group 1

alkali metals

Group 2

alkaline earth metals

Group 3-12

transition metals

Group 17

halogens

Group 18

Noble gases

AMU

atomic mass unit

Methane

a major component of natural gas

Ethanol

grain alcohol

Alcohol

things with OH on it

Isotopes

the same number of protons but different neutrons

Isomers

different chemical structures but the same formula

Cis

next to

Trans

across

Ions

charged atom or molecule made up of one or more molecules

Recall

number of protons defines the identity of an element

Cation

positive ion

Examples of cations

 iron, copper, zinc, silver, ammonium

Examples of anions

sulfide, nitrate, oxide, fluoride, chloride, bromide, iodine

Law

is a measured relationship between two variables

hypothesis

is a scientific guess

Theory

is an explanation and explains why or how

Purpose

state the problem

Research

find out about the topic

Experiment

determine the experiment

Macroscopic

big picture (what I can see or hear)

Microscopic

at the level of atoms and molecules

Physical State of Matter

solid, liquid, gas, plasma

Plasma

a material made up of stars

Mixtures

can be separated physically

Compounds

can be separated chemically

Physical Change

same substance presents a different physical setting