Unit 1 Flashcards by Nasierra Atwood

What is chemistry?

The study of matter and the changes it undergoes

How well did you know this?

Not at all

Perfectly

What is matter?

Anything that has mass and takes up space

How well did you know this?

Not at all

Perfectly

What is an atom?

Smallest amount of an element (ex. 1 gram of Copper)

How well did you know this?

Not at all

Perfectly

What is a molecule?

Smallest amount of a compound (ex. 1 molecule of h20)

How well did you know this?

Not at all

Perfectly

What is a compound?

A substance composed of two or more elements

How well did you know this?

Not at all

Perfectly

What are the four states of matter?

Solid, liquid, gas, plasma

How well did you know this?

Not at all

Perfectly

What is a pure substance?

An element or compound

How well did you know this?

Not at all

Perfectly

What is a mixture?

A combination of two or more pure substances, or mixtures

How well did you know this?

Not at all

Perfectly

What are components?

Pure substances within a mixture

How well did you know this?

Not at all

Perfectly

What is a homogeneous mixture?

A mixture that is uniform throughout

How well did you know this?

Not at all

Perfectly

What is a heterogeneous mixture?

A mixture that is not uniform throughout

How well did you know this?

Not at all

Perfectly

What is a solution?

Homogeneous mixture

How well did you know this?

Not at all

Perfectly

What is a phase?

A distinctly different region within a mixture

How well did you know this?

Not at all

Perfectly

What is separation by inspection?

Usually only works for solids

How well did you know this?

Not at all

Perfectly

What is filtration?

Does not work for solutions / homogeneous mixtures

How well did you know this?

Not at all

Perfectly

What is distillation?

The process of heating a liquid to the boiling point, condensing the heated vapor by cooling and returning either a portion of, or none of, the condensed vapors to the distillation vessel

How well did you know this?

Not at all

Perfectly

What is centrifigation?

Spinning a serum / liquid so the heavier stuff goes to the bottom

How well did you know this?

Not at all

Perfectly

What is chromatography?

works with polar and nonpolar molecules and a solvent is pushed through to separate them through polarity

How well did you know this?

Not at all

Perfectly

What is a property?

A characteristic that allows one substance to be distingushed from another

How well did you know this?

Not at all

Perfectly

What is a physical property?

a characteristic that can be observed or measured without changing the identity of a substance (color, melting point, boiling point etc)

How well did you know this?

Not at all

Perfectly

What is a chemical property?

describes the way a substance may react to another (ex, flammability oxidation)

How well did you know this?

Not at all

Perfectly

What is an intensive property?

a property that does not depend upon the amount of the substance (ex. temperature, density, boiling point)

How well did you know this?

Not at all

Perfectly

What is an extensive property?

a property that depends on the amount of matter in a sample (ex. mass, volume)

How well did you know this?

Not at all

Perfectly

What is a physical change?

A change in which the form or appearance changes, but no new substances are formed

How well did you know this?

Not at all

Perfectly

What is a chemical change?

when a substance changes chemically into another substance

What is a change of state?

the physical change from one state of matter to another. all changes are physical

S to L

melting

S to G

sublimation

L to S

freezing

L to G

vaporization / evaporation

G to L

condensation

G to S

vapor deposition

What is qualitative data?

a measure that is reported without a number and unit (ex. the coffee is hot, the barbell is heavy)

What is quantitative data?

a measurement reported with a number and a unit (ex. 13)

k, 10^3

kilo

d, 10^-1

deci

c, 10^-2

centi

m, 10^-3

milli

u, 10^-6

micro

n, 10^-9

nano

How to use prefixes?

Start with the prefix unit on the left and the base unit on the right

What is accuracy?

how close a measurement is to the true value

What is precision?

how close a series of measurements are to one another (repeatability)

What is a random error?

left and right of true value, no repeatability

What is a systematic error?

a consistent difference between the measured values and true values

What is a certain digit?

The numbers read from a measuring instrument

What is an uncertain digit?

a digit that must be estimated

What are significant digits?

all certain + one uncertain, also called significant figures or sig figs

How do you read a graduated cylinder?

bottom of the meniscus

Rule #1 for sig figs

non-zero numbers are significant (ex. 63.5 = 3 sig figs)

rule #2 for sig figs

zeros between nonzero digits are significant (ex. 1001 = 4 sig figs)

rules #3 for sig figs

Zeros at the beginning of a number are never significant (ex. 0.00506 = 3 sig figs)

rule #4 for sig figs

Zeros that appear to the right of a nonzero number in a measurement that has a decimal point are always significant (ex. 105.00 = 5 sig figs)

rule #5 for sig figs

When a number ends in zeros, but has no decimal point, the zeros are not significant (ex. 1000 = 1 sig fig)

What are two situations in which the number has an unlimited amount of sig figs?

A counting number (ex. 19 students, 40 pennies) and a defined number (ex. 60 seconds in 1 minute)

When doing word problems, what do you start with?

What's not a question

Mass =

density x volume

volume =

mass/density

density =

mass / volume

density of h2o

1 g/mL

Boiling point of h2o

100 degrees Celcius

Freezing H2O

0 degrees C

Tf = (1.8) x (Tc) + 32

Celcius to Farenheit

Tc = (Tf - 32) / 1.8

Farenheit to Celcius

Tc = Tk - 273

Kelvin to Celcius

Tk = Tc + 273

Celcius to Kelvin