Review Chapter

Question 1

What is a measurement?

Answer 1

Must include:

1. A number
2. A scale (Unit)

**a measurement always has some degree of uncertainty. The uncertainty of a measurement depends on the precision of the measuring device.**

Question 2

What is the difference between a fundamental and derived unit?

Answer 2

• A unit not listed in the SI table is derived.
• Ex: A unit such as volume that is based on a fundamental unit (meter) is called a “derived unit.”

Question 3

What’re the fundamental SI units?

Answer 3

Question 4

What’re the common SI prefixes and their meaning?

Answer 4

These change the size of the fundamental unit

Question 5

What is the definition of precision?

Answer 5

• It refers to the degree of agreement among several measurements of the same quantity.
• Precision reflects the reproducibility of a given type of measurement.
• We assume that the average of a series of precise measurements (which should “average out” the random errors because of their equal probability of being high or low) is accurate, or close to the “true” value.

***Precision is an indication of accuracy only if there are no systematic errors.

Question 6

What is the definition of accuracy?

Answer 6

refers to the agreement of a particular value with the true value.

Question 7

What is a random error?

Answer 7

• (also called an indeterminate error)
• means that a measurement has an equal probability of being high or low.
• This type of error occurs in estimating the value of the last digit of a measurement.

Question 8

What is a systematic error?

Answer 8

• (or determinate error).
• This type of error occurs in the same direction each time; it is either always high or always low.

Question 9

What’re the 3 rules for counting significant figures? Include 3 sub rules for counting zeros.

Answer 9

1. Nonzero integers. Nonzero integers always count as significant figures.
2. Zeros. There are three classes of zeros:
   
   1. Leading zeros are never significant figures.
   2. Captive zeros are always signifi‑ cant figures.
   3. Trailing zeros are sometimes sig‑ nificant figures.
3. Exact numbers never limit the number of significant figures in a calculation.

Question 10

What’re the Rules for Significant Figures in Mathematical Operations?

Answer 10

• For multiplication and division: significant figures are counted.
• For addition and subtraction: decimal places are counted.

**Note: normal rounding ruels apply**

Question 11

What is dimensional anaylsis or unit factor method?

Answer 11

to convert a given result from one system of units to another.

Question 12

What is the formula for temperature of kelvin? Celsius?

Answer 12

T_k = T_c + 273.15

Question 13

What is the formula to convert Fahrenheit Celsius temperature T_C? And T_F?

Answer 13

• T_C = (5/9)(T_F - 32)

T_F = (9/5)*T_{C + 32}

Question 14

What is the formula for density?

Answer 14

D = Mass/Volume

Question 15

1. What is matter?
2. What’re the 3 stages of matter?

Answer 15

1. Anything occupying space and having mass, is the material of the universe.
2. Stages of matter:
   
   1. Solid: is rigid; it has a fixed volume/shape.
   2. Liquid: A liquid has a definite volume but no specific shape; it assumes the shape of its container.
   3. Gas: no fixed volume or shape; it takes on the shape and volume of its container.

**Most matter consists of mixtures**

Question 16

1. What is a mixture?
2. What’re the types of mixtures?

Answer 16

1. mixtures are of pure substances. Wood, gasoline, wine, soil, and air all are mixtures. The main characteristic of a mixture is that it has variable composition.
2. Types:
   
   1. homogeneous: having visibly indistinguishable parts. *Also called, solution
   2. heterogeneous: having visibly distinguishable parts

Question 17

What is a pure substance?

Answer 17

A pure substance is one with constant composition

Question 18

What is a physical change?

Answer 18

• A physical change is a change in the form of a substance, not in its chemical composition.
• A physical change can be used to separate a mixture into pure compounds, but it will not break compounds into elements.

Question 19

What is distillation?

Answer 19

• important method for separating the components of a mixture
• works very well when only one component of the mixture is volatile.

Question 20

What is filtration?

Answer 20

• method of separation used when a mixture consists of a solid and a liquid.
• The mixture is poured onto a mesh, such as filter paper, which passes the liquid and leaves the solid behind.

Question 21

What is chromatography?

Answer 21

• method of separation
• a series of methods that use a system with two phases (states) of matter:
  
  • mobile phase: is either a liquid or a gas
  • stationary phase: is a solid

Question 22

What is the definition of volatile?

Answer 22

The term volatile refers to the ease with which a substance can be changed to its vapor.

Question 23

What is a compound?

Answer 23

is a substance with constant composition that can be broken down into elements by chemical processes.

Question 24

What is a chemical change?

Answer 24

change is one in which a given substance becomes a new substance or substances with different properties and different composition.

Question 25

What are elements?

Answer 25

are substances that cannot be decomposed into simpler substances by chemical or physical means.

Question 26

What is the organization of matter?

Answer 26

See image

Question 27

What is energy?

Answer 27

The ability to do work or produce heat

Question 28

What is work?

Answer 28

is defined as force acting over a distance

Question 29

What is the Law of Conservation of Energy?

Answer 29

states that energy can be converted from one form to another, but the total quantity of energy is not changed; that is, the energy content of the universe is constant.

Question 30

What is kinetic energy?

Answer 30

Energy of motion

Question 31

What is potential enery?

Answer 31

defined as stored energy due to position

Question 32

What is a joule?

Answer 32

fundamental unit of energy in science is the joule

Question 33

What is a mole?

Answer 33

a unit for counting atoms and molecules. 1 mole = 6.022 x 10²³