AP Chem Chapter 1 Flashcards Preview

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Flashcards in AP Chem Chapter 1 Deck (49)
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1
Q

what is the scientific method

A

the process of studying natural phenomena, involving observations, forming laws and theories, and testing of theories during experimentation

2
Q

what are the three main steps in the scientific method

A
  1. making observations
  2. formulating hypotheses
  3. performing experiments
3
Q

what is a theory

A

a set of tested hypotheses that gives an overall explanation of some natural phenomenon

4
Q

what is the difference between an observation and a theory

A

an observation is something that is witnessed and can be recorded. a theory is an interpretation, a possible explanation of why nature behaves a certain way

5
Q

what is a natural law

A

a statement that expresses generally observed behavior

6
Q

what is the difference between a theory and a law

A

a law summarizes what happens, a theory attempts to explain why it happens

7
Q

what is the SI system

A

international system of units based on the metric system and units derived from the metric system

8
Q

what is the difference between mass and weight

A

mass is a measure of the resistance of an object to a change in its state of motion
weight is a measure of the force that gravity exerts on an object

9
Q

do all measurements have some degree of uncertainty

A

yes

10
Q

true or false: we customarily report a measurement by recording to the first uncertain digit

A

true

11
Q

what are sig figs

A

the certain digits and the first uncertain digit of a measurement

12
Q

what is accuracy

A

the agreement of a particular value with the true value

13
Q

what is precision

A

the degree of agreement among several measurements of the same quantity

14
Q

what is a random error

A

a measurement has an equal probability of being high or low

15
Q

what us a systemic error

A

occurs in the same direction each time; either always high or always low

16
Q

under what circumstances is high precision among several measurements an indication of accuracy

A

if systemic errors are absent

17
Q

do you round sequentially?

A

no. the number 6.8347 rounded to 3 sig figs is 6.83, not 6.84

18
Q

do exact numbers ever limit sig figs

A

no

19
Q

what is dimensional analysis

A

a method used to convert from one unit to another

20
Q

what is the equation to find kelvin temperature

A

K = C + 273

21
Q

what is the equation to find fahrenheit temp or celsius temp

A

F = 1.8C + 32

22
Q

what temp is the same for both celsius and fahrenheit

A

-40

23
Q

what is density

A

mass of a substance per unit volume of that substance

24
Q

what is the equation for density

A

d=m/v

25
Q

what is the density of water

A

1 g/cm3

26
Q

does density depend on how much of a substance you have

A

no, it stays constant no matter how much u have

27
Q

what is matter

A

anything that takes up space and has mass

28
Q

volume and shape of a solid

A

both fixed

29
Q

volume and shape of a liquid

A

definite volume, indefinite shape

30
Q

volume and shape of a gas

A

neither fixed

31
Q

what are the main characteristics of a mixture

A

has a variable composition

can be separated into pure substances by physical means

32
Q

what are the two subcategories of mixtures

A

homogeneous and heterogenous

33
Q

what is a homogeneous mixture

A

a mixture with visibly indistinguishable parts

34
Q

what is a heterogeneous mixture

A

a mixture that has visibly distinguishable parts

35
Q

what is another name for a homogeneous mixture

A

a solution

36
Q

what are the two subcategories of matter

A

mixtures and pure substances

37
Q

what is a pure substance

A

has a constant composition

38
Q

what are physical changes

A

a change in the form of a substance, but not in its chemical composition

39
Q

can physical changes be used to change break pure substances into elements

A

no

40
Q

what are the 2 subcategories of pure substances

A

elements and compounds

41
Q

what is an element

A

a pure substance that cannot be broken down into simpler substances

42
Q

what is a compound

A

a pure substance that can be broken down into its component elements by chemical means

43
Q

what is distillation

A

a method for separating mixtures based on the differences in volatility of the components

44
Q

what does volatile mean

A

it refers to the ease with which a substance can be changed to its vapor

45
Q

how does distillation work

A
  1. a mixture is heated
  2. the most volatile component vaporizes at the lowest temp; then it passes through a cold tube to condense back into a liquid in a separate container
46
Q

what is filtration

A

a method for separating mixtures made of a solid and a liquid

47
Q

what is chromatography

A

a method for separating mixtures that works with two phases of matter, a stationary phase (a solid) and a mobile phase (a liquid or a gas)

48
Q

why does chromatography work

A

bc the components of a mixture have different affinities for the two phases and move through them at different rates

49
Q

what is a chemical change

A

a change in which a given substance becomes a new substance or substances with different properties and different compositions