Chemistry - Ch 1

Question 0

Matter

Answer 0

Physical material of the universe; anything that has mass and occupies space

Question 1

Chemistry

Answer 1

Study of materials and the changes that materials undergo

Question 2

Property

Answer 2

Characteristic that allows us to recognize a particular type of matter and to distinguish it from other types

Question 3

Elements

Answer 3

Basic substances; about 100 in world

Question 4

Atoms

Answer 4

Infinitesimally small building blocks of matter

Question 5

Molecules

Answer 5

Combo of 2+ atoms joined in specific shapes

Question 6

States of matter

Answer 6

Gas, liquid, solid

Question 7

Gas

Answer 7

Vapor; no fixed volume or shape; conforms to volume & shape of its container

Question 8

Liquid

Answer 8

Distinct volume, no specific shape; assumes shape of container

Question 9

Solid

Answer 9

Definite shape & volume

Question 10

Pure substance (substance)

Answer 10

Matter with distinct properties & a composition that does not vary from sample to sample

Question 11

Compounds

Answer 11

Substances composed of 2+ elements; contain 2+ kinds of atoms

Question 12

Mixtures

Answer 12

Combos of 2+ substances in which each substance retains its own chemical identity

Question 13

Law of constant composition (law of definite proportions)

Answer 13

Observation that the elemental composition of a pure compound is always the same; put forth by Louis Proust, ~1800

Question 14

Solutions

Answer 14

Homogeneous mixtures

Question 15

Physical properties

Answer 15

Observed w/o changing the identity & composition of the substance

Question 16

Chemical properties

Answer 16

Describe the way a substance may change (react) to form other substances

Question 17

Intensive properties

Answer 17

Properties like temperature, melting point, density; do not depend on the amount of the sample being examined; can be used to ID substances

Question 18

Extensive properties

Answer 18

Depend on quantity of sample (ex. Mass, volume)

Question 19

Physical change

Answer 19

Substance changes physical appearance but not composition (same substance b4 & after)

Question 20

Chemical change/reaction

Answer 20

Substance is transformed into a chemically different substance (hydrogen burning, changing to water; penny giving off a gas in nitric acid)

Question 21

Filtration

Answer 21

Separating a mixture into component parts

Question 22

Distillation

Answer 22

Part of separating components of a homogeneous mixture; depends on different abilities of substances to form gases (evaporating water from salt water leaving only salt)

Question 23

Chromatography

Answer 23

“Writing of colors”; abilities of substances to adhere to surfaces of various solids (paper, starch); can be used to separate mixtures

Question 24

Metric system

Answer 24

Units used for scientific measurements

Question 25

SI units

Answer 25

Systeme International d'Unites; 7 base units from which all other units are derived (kg, meter, second, Kelvin, mole - amt of substance; ampere - electric current; candela (cd) - luminous intensity)

Question 26

Giga (G)

Answer 26

10^9

Question 27

Mega (M)

Answer 27

10^6

Question 28

Kilo (k)

Answer 28

10^3

Question 29

Deci (d)

Answer 29

10^-1

Question 30

Centi (c)

Answer 30

10^-2

Question 31

Milli (m)

Answer 31

10^-3

Question 32

Micro (mu)

Answer 32

10^-6

Question 33

Nano (n)

Answer 33

10^-9

Question 34

Pico (p)

Answer 34

10^-12

Question 35

Femto (f)

Answer 35

10^ -15

Question 36

Mass

Answer 36

Measure of the amount of material in an object

Question 37

Temperature

Answer 37

Measure of hotness or coldness of an object

Question 38

Celsius

Answer 38

Everyday scale in most countries; based on 0 freezing, 100 boiling; C = 5/9 (F-32)

Question 39

Fahrenheit

Answer 39

Temp scale in US; F= 9/5 (C) + 32

Question 40

Kelvin

Answer 40

K= C + 273.15

Question 41

Density

Answer 41

Amount of mass in a unit volume of a substance; = mass/volume

Question 42

Exact numbers

Answer 42

Those whose values are known exactly

Question 43

Inexact numbers

Answer 43

Those whose value a have some uncertainty

Question 44

Precision

Answer 44

How closely individual measurements agree with one another

Question 45

Accuracy

Answer 45

How closely individual measurements agree with the correct/true value

Question 46

Significant figures

Answer 46

All digits of a measured quantity, including the uncertain one; zeroes btwn non zeroes always significant; zeroes @ beginning never significant; zeroes @ end significant if # has a decimal

Question 47

Dimensional analysis

Answer 47

Aid in problem solving

Question 48

Scientific method

Answer 48

Dynamic process to answer questions about our physical world; observations/experiments lead to scientific laws; observations also lead to tentative explanations (hypotheses); hypothesis tested/refined --> theory may develop

Question 49

Scientific laws

Answer 49

General rules that summarize how nature behaves