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Flashcards in Chapter 2 Deck (60):
1

What is work?

any activity that requires energy

2

what is energy?

ability to do work

3

what are the two types of energy?

Potential energy and kinetic energy

4

What is kinetic energy?

energy of motion

5

what is potential energy?

stored/inactive energy

6

What is heat? how fast are the particles?

thermal energy, the faster the particle the more thermal energy

7

What is the SI unit of energy and work?

Joules (J)

8

what is a calorie?

it is the amount of energy needed to raise the temperature of 1g° of water by 1°C

9

1 calorie = __J, is it exact?

1 calorie= 4.184 J, yes it is exact

10

what is the coldest temperature on the Calvin scale called? what is it's value in 0 °C?

absolute zero, 273 °C

11

1 K= __°C

1 K= 1°C

12

formula to convert °C to K?

K= ___+273

13

what is matter?

anything that has mass and takes up space

14

what is a pure substance?

matter with fixed or constant composition

15

what are the types of pure substances?

element and compund

16

what is an element?

an element is composed of only one kind of material/atom

17

what is a compound?

two or more chemically combined atom in the same proportions (atoms held together by bonds, therefore they can only be broken by chemical means)

18

what are atoms held together by?

attraction forces called bonds

19

how do you separate pure substances?

by chemical means, you cant separate them by physical means.

20

what is a mixture?

Two or more substances physically mixed, therefore physical processes can separate mixtures.

21

What are the classification of mixtures?

heterogeneous mixture and homogeneous mixture

22

what is a heterogeneous mixture?

a heterogeneous mixture doesn't have a uniform composition.

23

what is a homogeneous mixture?

A homogeneous mixture is any mixture that is uniform in composition throughout. ex: solution

24

What does filtration separate? (states of matter)

mixtures, separates solids from liquids

25

What are the states of matter?

solid, liquid and gas.

26

What are physical properties?

they are characteristics that can be observed or measured without affecting identity of substance

27

what are physical changes?

when appearances/states of matter change, but the composition is the same

28

What is the melting point(mp)?

the point where solids are converted to liquids

29

Is energy released or absorbed at melting point?

Energy is absorbed

30

What is the freezing point? (fp)

the point where liquids are converted to solids

31

Is energy released or absorbed at freezing point?

Energy is released

32

What is evaporation?

process where water molecules acquire sufficient kinetic energy to become gas, does not have to be at boiling point

33

What is the boiling point? (bp)

All molecules within a liquid gains enough energy to become a gas

34

What is condensation?

when heat is removed from gas matter to become a liquid matter

35

What is boiling?

The change of liquid to gas at boiling point

36

What is sublimation?

when solid changes to a gas directly.

37

What is deposition?

When gas changes to a solid directly

38

What is a chemical property?

The properties that indicate the ability of a substance to change into a new substance

39

What is a chemical change?

original substance converted to new substance with different composition and new physical and chemical properties
ex) rusting of iron, burning of wood.

40

What is the specific heat?

# of joules/calories needed to change 1g of substance by 1°C

41

Formula for specific heat?

Specific heat= heat (j or cal) / (mass (g) * change in temperature (°C))

42

Formula for heat?

Heat= mass * change of temperature * specific heat

43

What is the order of energy sources in your body?

Carbohydrates, fats, proteins

44

What is a Calorie?

1000 cal or 1 kcal
1 Cal= 1 kcal= 1 cal

45

Formula for converting C to F:

(1.8)(C)+32

46

Formula for converting F to C.

(F-32)/(1.8)

47

What are the ways of separating a mixture?

Filtration and chromatography

48

What is chromatography?

separates different component of liquids.

49

What are properties of solids?
(shape, volume, attraction, movement)

Definite shape and definite volume
strong attractive forces hold particles in rigid pattern
particles vibrate in place

50

What are the properties of liquids?
(shape, volume, attraction, movement)

Definite volume and definite shape
Particles move slowly in random directions
only sufficiently attracted to each other to maintain volume

51

What are the properties of gases?
(shape, volume, attraction, movement)

No definite shape and no definite volume
little attraction in particles
particles far apart and fast.

52

What are the similarities and difference between boiling point and condensation?

condensation and boiling point occurs at the same point, except heat is removed in condensation and at boiling point, heat is added.

53

State the steps of a heating curve of water
(from lowest temperature/least heat to highest temperature/most heat)

Solid, solid + liquid (melting), liquid, Liquid and gas (boiling), gas

54

State the steps of a cooling curve of water
(from highest temperature/most heat to lowest temperature/least heat

steam, water + steam (condensation), water, water + ice (freezing), ice

55

What is the order of energy sources in your body?

Carbohydrates, fats, protein

56

What is a Calorie?

1000 cal or 1kcal

57

1 Cal = ___kJ= ___J
1 Cal= __kcal=____cal

1 Cal = 4.184kJ= 4184J
1 Cal= 1kcal=1000cal

58

How many kj/g and kcal/g do you need to burn a carbohydrate?

17 kJ/g
4 kcal/g

59

How many kj/g and kcal/g do you need to burn a fat?

38 kJ/g
9 kcal/g

60

How many kj/g and kcal/g do you need to burn a protein?

17 kJ/g
4 kcal/g