Chapter 1: Matter and Measurement

Chapter 1 Problem Set

Pages 51-55

4, 6, 8, 16, 34, 46, 54,60

1.1CLASSIFYING MATTER

States of Matter

What are the 3 states of matter?

Kinetic-Molecular Theory

What is the energy of motion that particles possess?

What effect does an increase in temperature have upon particles?

Matter at the Macroscopic Level and Particulate Level

What is meant by the statement, “Chemists carry out experiments at the macroscopic level, but they think about chemistry at the particulate level”?

Pure Substances

What are some characteristic properties of a pure substance?

A pure substance cannot be separated into two different species by a physical process.

Mixtures: Heterogeneous & Homogeneous

What are some examples of a heterogeneous mixture?

What are some examples of a homogeneous mixture?

Is air a solution?

1.2ELEMENTS & ATOMS

What is an element?

How many elements are found in nature?

What is an atom?

1.3COMPOUNDS AND MOLECULES

What is the difference between NO and No?

What is a chemical compound?

Are the characteristic properties of a compound different than those of the elements which make up the compound?

For example…

1.4PHYSICAL PROPERTIES

What are physical properties?

Density

What is the equation for calculating density?

Knowing the density and mass of an object, how is its volume calculated?

Knowing the density and volume of an object, how is its mass calculated?

Example 1L.1Density

Calculate the mass of magnesium that occupies the same volume as 94.3 g of iron.

Density of Mg = 1.74 g/cm3 and Fe = 7.87 g/cm3.

Exercise 1L.1

A cubic block of pure metal which is 4.0 cm long weighed1.26 lb. (1 lb = 453.6 g)

The metal is:

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

  1. Al, d = 2.70 g/cm3
  2. Cu, d = 8.96g/cm3
  3. Pb, d = 11.4g/cm3
  4. Ag, d = 10.5g/cm3
  5. Au, d = 19.3g/cm3

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Temperature

Temperature is the property of matter that …

The freezing point and boiling point of water on the Celsius and Fahrenheit scales are …

The relationship between 0F and 0C is …

The Kelvin Temperature Scale

The relationship between temperatures in K and 0C is …

Temperature Dependence of Physical Properties

What is the seasonal “turnover” of water in lakes?

Extensive and Intensive Properties

Extensive properties depend on …

Intensive properties are those that …

Exercise 1L.2

All of the following are intensive properties EXCEPT

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

  1. color
  2. density
  3. heat
  4. melting point
  5. solubility

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

1.5Physical and Chemical Change

What is a physical change?

What is a chemical change?

Exercise 1L.3

Which of the following results in a physical change and not a chemical change?

  1. A banana peel turning a dark color
  2. The development of a Polaroid picture
  3. Making a cup of tea from a tea bag and hot water
  4. The souring of milk
  5. Bleaching of hair

Exercise 1L.4

Which of the following is (are) chemical change(s)?

  1. rusting
  2. boiling
  3. cooking

a. 1 onlyb. 3 onlyc. 1 and 2 onlyd. 1 and 3 only e. 1, 2, and 3

1.6UNITS OF MEASUREMENT

What are some examples of qualitative measurements?

How are they different from quantitative measurements?

SI Units

What are the SI base units?

metric prefixes Appendix C

1.7USING NUMERICAL INFORMATION

For each conversion factor, the numerator of the factor must be equivalent to the denominator.

A single relationship such as 1 cal = 4.184 J gives two conversion factors.

Initial quantity x conversion factor(s) = desired quantity

Conversion factor used must cancel given units

Example 1L.2 Conversions

The average velocity of hydrogen molecules at O°C is 1.69 x 105 cm/s. Convert this value to miles per hour using the following conversion factors.

1 in. = 2.54 cm

1ft. = 12 in

1 mile = 5280 ft

1min.=60s

1 hr. = 60 min

Exercise IL.5

All of the following are equivalent EXCEPT

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

  1. 0.001 mL = 10-6L
  2. 10 cm = 100 mm
  3. 10 C = 1 K
  4. 100 g = 10-3 g
  5. 10 Mg = 104 kg

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

EXAMPLE IL.3 Units of Volume

A volumetric flask has the volume of 0.001000 L. What is its volume in cubic centimeters and milliliters?

EXAMPLE lL.4 Density in Different Units

A piece of iron with a volume of 1.452 gal. weighs 95.31 Lbs. Calculate the density of iron in scruple/drachm. Some conversion factors are:

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

1.00 L = 0.264 gal

1.000 kg = 2.205 lb

1.000 scruple = 1.296 g

1.000 mL = 0.2816 drachm

1000 g = 1 kg

1000 mL = 1.00 L

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Exercise lL.6

The heat of combustion of glucose, C6H12O6, is -15600 J.g-1. Expressed in kJ kg-1, the heat of combustion is

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

a. -1.56 x 101 kJ.kg-1

b. -1.56 x 104 kJ.kg-1

c. -1.56 x 106 kJ.kg-1

d. -1.56 x 107 kJ.kg-1

e. -1.56 x 109 kJ.kg-1

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Precision, Accuracy, and Experimental Error

What is meant by the precision of a measurement?

What is accuracy?

What is the average deviation?

EXAMPLE lL.5 Precision and Accuracy

Student A titrated a 1.000 g sample of NaHCO3 with a sodium hydroxide using a buret with markings every tenth of a mL, whereas student B used a buret with markings at every mL. The following results were reported:

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Student A

35.12 mL

34.88

35.24

34.75

Ave= 35.10

Deviation from Average

Student B

35.6 mL

35.2

36.0

34.9

Ave = 35.4

Deviation from Average

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Calculate the average deviation for each set of data. Whose results are more precise?

Significant Figures

A calculated result can be no more precise than the least precise piece of information that went into the calculation.

Guidelines for Determining Significant Figures

Rule1

To determine the number of significant figures in a measurement that contains a decimal, read the number from left to right and count all digits, starting with the first digit that is not zero.

Rule 2

When adding or subtracting numbers, the number of decimal places in the answer should be equal to the number of decimal places in the number with the fewest places.

Rule 3

In multiplication or division, the number of significant figures in the answer should be the same as that in the quantity with the fewest significant figures.

Rule 4

When a number is rounded off, the last digit to be retained is increased by one only if the following digit is 5 or greater.

Exercise lL.7

The number of significant figures in 405000 is

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

a. 2

b. 3

c. 4

d. 5

e. 6

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018

Exercise lL.8

Four samples were weighed using four different balances. (All are as precise as indicated by the individual masses.) The masses are 0.94 kg, 58.2 g, 1.55 g, and 250 mg. The total mass should be reported as …

Exercise 1L.9

A physics student measured the electronic charge of one electron by using the Millikan oil droplet experiment and obtained the following three values:

4.635 x 10-10 esu

4.923 x 10-10 esu

4.768 x 10-10 esu

Which of the following values should he report?

4.7753 x 10-10 esu

4.775 x 10-10 esu

4.78 x 10-10 esu

4.8 x 10-10 esu

5 x 10-10 esu

1.8 PROBLEM SOLVING

Step 1. Define the problem.

Step 2. Develop a plan.

Step 3. Execute the plan.

Step 4. Is the answer reasonable?

EXAMPLE 1L.6 Problem Solving

A 0.680 g sample of paraffin oil with a density of 0.858 g/cm3 was spread over the surface of water in a large beaker which has a diameter of 154 mm. How thick is the oil layer in centimeters?

Chapter 1 Notes.doc/Sheri FecherPage 110/4/2018