Science and Measurement

Question 1

What is chemistry

Answer 1

the study of matter and energy

Question 2

matter

Answer 2

anything that has mass and occupies space

Question 3

elements

Answer 3

the simplest form of matter that has distinct physical and chemical properties and cannot be broken down chemically into simpler, stable substances; building blocks for everything

Question 4

atom

Answer 4

the smallest amount of an element that still has the characteristics of that element

Question 5

chemical bonds

Answer 5

An attraction between atoms of different elements; can be broken and re-formed

Question 6

compound

Answer 6

a chemical combination of elements that has its own set of properties and a definite composition

Question 7

The two types of pure substances:

Answer 7

elements and compounds

Question 8

mixture

Answer 8

two or more pure substances physically combined; no definite composition and can be heterogeneous or homogeneous

Question 9

Homogeneous mixtures

Answer 9

also called solutions

Question 10

Which phases can solutions be found in?

Answer 10

gas, solid, aqueous

Question 11

Element examples

Answer 11

Hydrogen, sodium

Question 12

Compound examples

Answer 12

water (H2O), Table salt (NaCl)

Question 13

Heterogeneous mixture examples

Answer 13

oil and water mixture, chicken noodle soup

Question 14

homogeneous mixture examples

Answer 14

brass, vodka

Question 15

properties

Answer 15

characteristics by which something can be identified

Question 16

Physical Properties

Answer 16

describe or identify a substance w/o changing its chemical composition

Question 17

Physical Properties Examples

Answer 17

color, melting point, conductivity

Question 18

Chemical properties

Answer 18

characteristic chemical reactions a substance undergoes

Question 19

Extensive Properties

Answer 19

depend on the amount of a substance present

Question 20

Extensive properties examples

Answer 20

mass, volume

Question 21

Intensive properties

Answer 21

properties that are the same regardless of sample size

Question 22

Intensive properties Examples

Answer 22

density, color, melting point

Question 23

Physical Change

Answer 23

Chemical composition is not altered; Iron and sulfur can be mixed but remain iron and sulfur. They can be separated based on their different solubilities (another physical property).

Question 24

Reactant

Answer 24

starting material in a chemical change (reaction)

Question 25

product

Answer 25

resulting material in a chemical change (reaction)

Question 26

Chemical changes

Answer 26

alter the chemical structure of a substance by breaking and/or forming chemical bonds

Question 27

Mass

Answer 27

how much matter an object has; directly proportional to weight

Question 28

Energy

Answer 28

capacity to do work

Question 29

Law of Conservation of Energy

Answer 29

Energy cannot be created or destroyed but can be converted from one form to another

Question 30

Scientific Method

Answer 30

A process that combines observation, hypothesis, and experimentation

Question 31

Hypotheses

Answer 31

the initial explanation for some observed fact(s), based on observation/evidence; are to be revised and tested through experimentation

Question 32

Theories

Answer 32

explain and predict many different observations that are linked by the same underlying phenomena; generally widely accepted as valid explanations of phenomena

Question 33

Scientific Laws

Answer 33

observations that are always true; statements of a phenomenon w/o explanation

Question 34

Law of Conservation of Mass

Answer 34

in any chemical reaction or physical change, the total mass present after the change is equal to the total mass present before the change; discovered by Lavoisier; does not apply to nuclear reactions

Question 35

Base Units (fundamental units)

Answer 35

units defined by a particular physical measurement

Question 36

SI unit of length

Answer 36

meter, m

Question 37

SI unit of mass

Answer 37

Kilogram, kg

Question 38

SI unit of time

Answer 38

second, s

Question 39

SI unit of temperature

Answer 39

Kelvin, K

Question 40

SI unit for Amount of a Substance

Answer 40

Mole, mol

Question 41

Tera-

Answer 41

10^12

Question 42

Giga-

Answer 42

10^9

Question 43

Mega-

Answer 43

10^6

Question 44

Kilo-

Answer 44

10^3

Question 45

Deci-

Answer 45

10^-1

Question 46

Centi-

Answer 46

10^-2

Question 47

Milli-

Answer 47

10^-3

Question 48

Micro-

Answer 48

10^-6

Question 49

Nano-

Answer 49

10^-9

Question 50

Pico-

Answer 50

10^-12

Question 51

Qualitatitve

Answer 51

the identity or form of a substance present

Question 52

quantitative

Answer 52

the amount of a substance present

Question 53

accuracy

Answer 53

the closeness of the average of a set of measurements to the true value

Question 54

precision

Answer 54

the closeness of all of a set of measured values to one another

Question 55

significant digit

Answer 55

every digit that reflects the precision of the measurement, including the estimated digit at the end

Question 56

Density

Answer 56

the measure of how much mass something has relative to its volume; m/v

Question 57

Three temperature scales

Answer 57

Fahrenheit, Celsius, Kelvin

Question 58

Conversion from Fahrenheit to Celsius

Answer 58

C = 5/9(F-32) F = 9/5(C+32)

Question 59

Celsius to Kelvin

Answer 59

K= C+273.15