Scientific Measurements

Question 1

A collection of quantitative or numerical data that describes a property of an object or event.

Answer 1

Measurement

Question 2

How is a measurement made?

Answer 2

By comparing a quantity with a standard unit

Question 3

What unit system is used in chemistry?

Answer 3

The International System of Units (SI units)

Question 4

SI base unit of length

Answer 4

Meter (m)

Question 5

SI base unit of mass

Answer 5

Kilogram (kg)

Question 6

SI base unit of temperature

Answer 6

Kelvin (K)

Question 7

SI base unit of time

Answer 7

Second (s or sec)

Question 8

SI base unit of amount of substance

Answer 8

Mole (mol)

Question 9

SI base unit of electric current

Answer 9

Ampere (A or amp)

Question 10

SI base unit of luminous intensity

Answer 10

Candela (cd)

Question 11

What was the SI system formerly known as?

Answer 11

The Metric System

Question 12

Internationally adopted decimal system

Answer 12

The Metric System

Question 13

What converts base units into the units that are appropriate for common usage or appropriate measure?

Answer 13

Metric System Prefixes

Question 14

A measure of the amount of material in an object

Answer 14

Mass

Question 15

What is the SI base unit of mass and what is its metric system unit?

Answer 15

SI=kilogram, Metric=gram

Question 16

A measure of distance

Answer 16

Length

Question 17

What is the base unit of length?

Answer 17

Meter

Question 18

It is the “hotness and coldness” of an object that determines the direction of heat flow

Answer 18

Temperature

Question 19

What is the base unit of temperature?

Answer 19

Kelvin

Question 20

How do you convert Kevlin to Celsius?

Answer 20

K=C+273.15

Question 21

Celsius scale is based on the properties of ___

Answer 21

Water

Question 22

Kelvin scale is based on the properties of ___

Answer 22

Gases

Question 23

True or False: There are no negative Kelvin temps.

Answer 23

True

Question 24

What is the lowest possible temperature of Kelvin called?

Answer 24

Absolute Zero

Question 25

The length of a 20-peso bill is approximately ___ inches

Answer 25

6

Question 26

What is the approximate measurement of the tip of your thumb to the first joint?

Answer 26

1 inch

Question 27

What is the approximate height of a doorknob to the floor?

Answer 27

1 meter

Question 28

Quantities that are calculated form base units

Answer 28

Derived units

Question 29

Area and volume conversions are equivalent to ?

Answer 29

Length conversion raised to a power

Question 30

A physical property of a substance that consists of dividing an object's mass by its volume

Answer 30

Density (g/mL or g/cm^3)

Question 31

Numbers that are counted or given by definition

Answer 31

Exact numbers

Question 32

Numbers that depend on how they were determined (via scientific tools and human observation)

Answer 32

Inexact (measured) numbers

Question 33

Why are measured numbers inexact?

Answer 33

Scientific instruments have limitations (equipment errors) and individuals can read some tools differently (human error)

Question 34

Which digit is the uncertainty?

Answer 34

Last digit

Question 35

Refers to how closely individual measurements agree with the correct, or "true" value

Answer 35

Accuracy

Question 36

Refers to the measure of how closely individual measurements agree with one another

Answer 36

Precision

Question 37

How do you calculate for the percent error?

Answer 37

%error= error in measurement/accepted value*100

Question 38

Low error=?

Answer 38

High accuracy

Question 39

How do you calculate for the error in measurement?

Answer 39

experimentally determined value - accepted value

Question 40

The measure of how spread out numbers are relative to the average

Answer 40

Standard deviation

Question 41

How do you calculate for the Standard Deviation?

Answer 41

square root of [ (1/N) times Sigma i=1 to N of (xi - mu)^2 ]

Question 42

Which kinds of numbers have an infinite number of significant figures?

Answer 42

Exact and Defined numbers

Question 43

Dimensional analysis is used to ?

Answer 43

Change units