Unit 0

Question 1

Scientific Method

Answer 1

evidence based method of inquiry
-evidence is collected through a series of experiments that are as accurate/ unbiased as possible
-as more information is collected, conclusions and our understanding of science changes

Question 2

chemistry

Answer 2

the studdy of matter, its compositions, and its properties

Question 3

matter

Answer 3

anything that has volume and mass
-“anything that takes up space”

Question 4

composition

Answer 4

parts of matter present in specific proportions

Question 5

properties

Answer 5

the attributes to distinguish between matter (scent, color, temperature, etc)

Question 6

atoms

Answer 6

the smallest building block of matter

Question 7

molecules

Answer 7

groups of atoms that are the same atoms
-ex: O2

Question 8

compounds

Answer 8

groups of atoms that have different atoms
-ex: H2O

Question 9

elements

Answer 9

different atoms organized by mass on the periodic table

Question 10

Physical Properties

Answer 10

can be observed or seen without a change in composition
ex: color, shape, size, mass, texture, melting point, magnetism, density, mallubility, smell, temperature, state of matter etc.

Question 11

Chemical Properties

Answer 11

are observed/ measured only with a change in composition
ex: toxicity, reactivity, corrosiveness, flammability, acidity, radioactivity etc

Question 12

Physical Changes

Answer 12

change that does not alter the composition of the matter that undergoes the change
sign: phase change

Question 13

chemical changes

Answer 13

change that alters the composition of the matter that undergoest the change
signs: change in smell, color, texture, energy (glowing or on fire), pH, an new material forming (precipitate), a solid from a liquid

Question 14

pH

Answer 14

the strength of an acid or base

Question 15

error/uncertainty

Answer 15

the trustworthyness of a measure

Question 16

kilo (k)

Answer 16

1000 (10^3)

Question 17

milli (m)

Answer 17

0.001 (10^-3)

Question 18

micro (μ)

Answer 18

10^-6

Question 19

nano (n)

Answer 19

10^-9

Question 20

pico (p)

Answer 20

10^-12

Question 21

mass (unit)

Answer 21

gram (g)

Question 22

length (unit)

Answer 22

meter (m)

Question 23

time (unit)

Answer 23

second (s)

Question 24

temperature (unit)

Answer 24

Kelvin (K), Celcius (℃)

Question 25

amount (unit)

Answer 25

mole (mol)

Question 26

current (unit)

Answer 26

ampere (A)

Question 27

Add/Subtract significant figures

Answer 27

keep as many decimal places as the number with the least amount of sig figs
-ex: 2.11 + 3.0 + 1.013 = 6.1

Question 28

Multiply/Divide significant figures

Answer 28

keep as many significant figures as the number with the least amount of significant figures
-ex: 4.567 x 1.4 = 6.5

Question 29

Scientific Notation

Answer 29

A x 10^n
A is a number between 1 & 10
n is the exponent
-ex: 10^-3=0.001
-ex: 86,400 = 8.64 x 10^4

Question 30

Accuracy

Answer 30

how close a measured quantity is to the accepted value

Question 31

Precision

Answer 31

how close measured values are to each other
-shows reproducibility

Question 32

Average (x bar)

Answer 32

measures a central tendency of a set of numbers

Question 33

Standard Deviation

Answer 33

the amount of deviation from the average
(Spread)
-always rounded to one sig fig
-

Question 34

formula for average

Answer 34

X1+X2+X3…/n where n= number of measurements
-have the mean go out to the same amount of decimals as st. dev.
-ex: 5.20 +/- 0.05

Question 35

formula for standard deviation

Answer 35

√(x1-avg,)^2 + (x2-avg)^2 + …
————————————-
n-1

where n = number of measurements

Question 36

Density

Answer 36

property of a substance that can be calculated as mass/volume

Question 37

solution

Answer 37

a homogeneous mixture: a mixture where all the materials present are present in the same composition

Question 38

Graph

Answer 38

a diagram depicting the relation between variables

Question 39

variables

Answer 39

quantities that can change