Chemistry (Chapter 3)

Question 1

S1) Measurement

Answer 1

A quantitative description that includes both a number and a unit.

Question 2

S1) Scientific Notation

Answer 2

An expression of numbers in the form m x 10 ^n where m is equal to or greater than 1 and less than 10, and n is an integer.

Question 3

S1) In scientific notation, the coefficient is always a number greater than or equal to one or less than ten. The exponent is an integer.

Answer 3

S1) To evaluate accuracy of a measurement, the measured valued must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements.

Question 4

S1) Accuracy

Answer 4

The closeness of a measurement to the true value of what is being measured.

Question 5

S1) Precision

Answer 5

Describes the closeness, or reproducibility, of a set of measurements take under the same conditions.

Question 6

S1) Accepted value

Answer 6

A quantity used by general agreement of the scientific community.

Question 7

S1) Experimental Value

Answer 7

A quantitative value measured during an experiment.

Question 8

S1) Percent Error

Answer 8

The percent that a measured value differs from the accepted value.

Question 9

S1) Error

Answer 9

The difference between the accepted value and the experimental value.

Question 10

S1) Percent Error (formula)

Answer 10

The absolute value of the error divided by the accepted value, multiplied by 100%.

Question 11

S1) Toe evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements.

Answer 11

S1) Measurements must always be reported to the correct number of significant figures because calculated answers often depend on the number of significant figures in the values used in the calculations.

Question 12

S1) Significant Figures

Answer 12

All the digits that can be known precisely in a measurement, plus a last estimated digit.

Question 13

S1) How do you determine a significant figure in measurements? (6 steps)

Answer 13

1) Every non-zero digit is significant.
2) Zeros between nonzero areas are significant.
3) Left most zeros in front of non-zeros after a decimal are not significant. They are placeholders.
4) Zeros after a non-zero digit AND after a decimal are SIGNIFICANT.
5) Zeros at the right most end that lie to the left of an understood decimal point are NOT significant.
6) If a number is defined or counted, then a infinite number of significant..

Question 14

S2) International System of Units

Answer 14

The revised version of the metric system, adopted by international agreement in 1960.

Question 15

S2) All metric units are based on multiples of 10. As a result, you can convert between units easily.

Answer 15

S2) Scientist commonly use two equivalent units of measure, the degree Celsius and the kelvin.

Question 16

S2) Meter

Answer 16

The base unit of length in SI.

Question 17

S2) Liter

Answer 17

The volume of a cute measuring 10 centimeters on each edge; it is the common unprefixed unit of volume in the metric system.

Question 18

S2) Kilogram

Answer 18

The mass of 1 L of water at 4 degrees Celsius; it is the unit of mass in SI.

Question 19

S2) Gram (g)

Answer 19

A metric mass unit equal to the mass of 1cm^3 of water a 4 degrees Celsius.

Question 20

S2) Weight

Answer 20

A force that measures the pull of gravity on a given mass.

Question 21

S2) Energy

Answer 21

The capacity for doing work or producing heat.

Question 22

S2) Joule (J)

Answer 22

The SI unit of energy; 4.184 J equal one calorie.

Question 23

S2) Calorie (cal)

Answer 23

The quantity of heat needed to raise the temperature of 1g of pure water 1 degree Celsius.

Question 24

S2) Kilogram (kg)

Answer 24

The mass of 1 L of water at 4 degrees celsius; it is the base unit of mass in SI.

Question 25

S2) Temperature

Answer 25

A measure of the average kinetic energy of particles in matter; temperature determine the direction of heat transfer.

Question 26

S2) Celsius Scale

Answer 26

The temperature scale on which the freezing point of water is 0 degrees Celsius and the boiling point of 100 degrees Celsius.

Question 27

S2) Kelvin Scale

Answer 27

The temperature in which the freezing point of water is 273K and the boiling point is 373K; 0K is absolute zero.

Question 28

S2) Absolute Zero

Answer 28

The zero point on the Kelvin temperature scale, equivalent to -273.15 degrees Celsius.

Question 29

S2) Density

Answer 29

The ratio of the mass of an object to its volume.

Question 30

S2) Density is an intensive property that depends only on the composition of a substance, not on the size of the sample.

Answer 30

BLANK CARD.

Question 31

S3) Conversion Factor

Answer 31

A ratio of equivalent measurements used to convert a quantity from one unit to another.

Question 32

S3) When a measurement is multiplied by a conversion factor, the numerical value is generally changed, but the actual size of the quantity measured remains the same.

Answer 32

S3) Dimensional analysis is a powerful tool for solving conversion problems in which a measurement with one unit is changed to an equivalent measurement with another unit.

Question 33

S3) Dimensional Analysis

Answer 33

A technique of problem-solving that uses the units that are part of a measurement to help solve the problem.