Science 14 Unit A: Investigating Properties of Matter

Chapter 2

Pure Substances: Elements & Compounds pp. 22-39

WORKBOOK

Name: _____________________________

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2.1 – Putting the Pieces Together pp. 24-30

Read pp. 24-25

The Periodic Table

Element contains only one kind of atom

pure substance

o substance cannot be broken down into other substances

atoms are the smallest bit of matter

o Example: water (H20) is the combination of two hydrogen atoms and one

oxygen atom

Dmitri Mendeleev developed the first periodic table

o All elements known at the time were organized into groups with similar

properties to create a chart, which was used to predict other undiscovered

elements that were later added

o Scientific technique and apparatus advances clarified Mendeleev’s data and

new elements discovered matched predicted properties almost perfectly

o There are 118 known elements on the table today

Periodic tables may look different, but they all consistently

o look like a chart

o include information about one element in each square

usually at least contain the element name, symbol, and number

could also include state at room temperature, atomic mass, and other

details about the element

o place elements in the same location

Example: oxygen is always at group 16, period 2

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Elements are arranged in groups (vertical columns) and periods (horizontal rows)

o periods arranged in order of increasing mass

o groups organized based on similar physical and chemical properties

Example: nonreactive Noble Gases in group 18

TASK: Label the groups and periods on the following image.

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Read p. 26

Metals and Non-metals

The “staircase” line on the right side of the table separates the metals (left) and

non-metals (right)

Properties: Table 2.1 – p. 26

Metals Non-metals bright metallic shine (luster)

easily shaped (malleable)

solid at room temperature (except

mercury)

good conductor of heat and

electricity

dull, various colors (not shiny)

brittle

solid or gas at room temperature

(except bromine)

poor conductor of heat and

electricity

Metalloids are elements that are between the metals and non-metals

o have properties and characteristics of both metals and non-metals

the human body contains all types of elements (metal, non-metal, and metalloid)

o Exampe: iron used to release energy to cells

carbon is key for sugars, carbohydrates, and proteins

potassium helps maintain fluid balance in tissues

Read “Did You Know” and “Off the Wall” – p. 27

TASK: Highlight the “staircase” on the previous page image as well

as identify the metals, non-metals, and metalloids with different colors.

Discuss CYU – p. 30 #1-4

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Reading the Periodic Table

Investigation 2-A p. 28

The periodic table contains important information about the elements. To give you

practice using it, use the periodic table at the back of your textbook to find the

information needed to complete the chart below.

Element Name Symbol Period Group Metal or

Non-metal

State of

Matter

chromium

4 17

P

1 18

bohruim 7 synthetic

15 metal

14 non-metal

tin

Cl

Nb 5

Analysis

1. Which part of the table was easiest to complete: the ones with the element name,

the symbol, the period number or the group number?

2. Look at the elements that you classified as metals. On which side of the staircase

line are they located?

3. Some lines on the table only give you the group number and the period number.

How did you use this information to find the element name and symbol?

4. What patterns did you notice while looking at the element numbers in the periodic

table?

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Metal or Non-metal? BLM 2-2

Can you tell whether a substance is a metal or non-metal by looking at its properties?

Identify the substances shown here. Consider their characteristics, then place a checkmark in

each column that applies.

Is the substance a solid, liquid, or gas? Put your answer in the second-last column.

Decide whether the substance is metal or non-metal. Place your conclusion in the last column.

Substance Shiny

(lustrous)

Easily

Shaped

(malleable)

Conducts

Heat and

Electricity

Can be

Pulled into

a Wire

(ductile)

State

S = solid

L = liquid

G = gas

Metal or

Non-metal?

gold bar

s metal

neon sign

tin can

silver coins

magnesium fire starter

copper pipe

phosphorous glow stick

oxygen

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2.2 – Elements and Compounds pp. 30-34

Read pp. 30-31

Elements cannot be broken down into simpler substances

they are the simplest substance known

Compound substance made up of two or more different elements that are

chemically combined

See Classification of Matter Flowchart (Figure 2.9 – p. 31)

compounds can be broken apart into simpler substances through the process of a

decomposition reaction

o Example: Oxygen, O, is a pure substance, consisting of one element

Distilled water is a pure substance made of more than one element

H2O(l) = 2-H + 1-O

Hydrogen and Oxygen are chemically combined and form a compound

o Electrolysis of Water (decomposition rxn)

water is a pure substance molecule

compound that can be broken into elements

use electricity to “cut” water molecules

decompose into elements

2H2O(l) ⇌ 2H2(g) + O2(g)

Test for compounds released

hydrogen pop test (explosion)

flame test for oxygen (glowing splint reignites)

Everything is made from elements

Most substances in the world are compounds

Read “Career Connect” – p. 33

Discuss CYU – p. 34 #1-4

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Uses of Elements and Compounds BLM 2-3 Everything in the universe contains elements. Most things are compounds that are a combination of elements.

Use the knowledge you have gained in this unit to:

decide whether items are elements or compounds; and

match the common name of a substance to its scientific name and formula.

1. Complete the chart below. The first row has been done for you.

Substance Element or Compound? Uses

aluminum, Al(s) element baseball bats, foil, manufacturing

carbon, C(s)

carbon dioxide, CO2(g)

copper, Cu(s)

glucose, C6H12O6(s)

gold, Au(s)

helium, (He(g))

limestone (calcium

carbonate), CaCO3(s)

methane, CH4(g)

propane, C3H8(g)

silver, Ag(s)

sucrose, C12H22O11(s)

tungsten, W(s)

2. Many products have familiar names as well as the official IUPAC name scientists use. Match the

consumer products in column A with the appropriate IUPAC name and formula in column B by

writing the correct letter from B in the blank beside the correct term in A. The table on page 37 of

the science.connect 1 textbook will help you.

A B

i. baking soda

ii. used to bleach hair

iii. battery acid

iv. food seasoning

v. table salt

vi. road de-icer

vii. cleaner

(a) sulfuric acid (H2SO4(l))

(b) sodium phosphate (Na3PO4(s))

(c) sodium bicarbonate (NaHCO3(s))

(d) magnesium chloride (MgCl2(s))

(e) monosodium glutamate (NaC5H8NO4(s))

(f) hydrogen peroxide (H2O2(l))

(g) sodium chloride (NaCl(s))

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2.3 – Chemical Names and Formulas pp. 35-37

Read p. 35

In 1919 a group of chemists from around the world came together to form the

International Union of Pure and Applied Chemistry (IUPAC)

o They set an international standard for chemical symbols and names so they

would be consistent around the world

o Today all countries use these symbols

All element symbols use one or two letters, often the first letter of the name is used

o i.e. carbon = C

Once all letters were used, they used the first letter of the element name and a

second letter from the name

o i.e. calcium = Ca

Some elements were discovered when the Latin form of the word was used, and

given symbols based on their historic names

o i.e. lead (plumbum) = Pb

Read p. 36

Chemical formulas are used to represent compounds elements form.

formulas are made up of letters and numbers.

o letters indicate which element is in a substance,

o subscript numbers indicate the proportion on the element in the substance

o subscript letter tells you the state of matter

i.e. (s)=solid (l)=liquid (g)=gas

Example:

C6H12O6 (s) = 6 Carbon atoms

12 hydrogen atoms

6 oxygen atoms

in a solid state

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Discuss CYU – p. 37 #1-3

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Chemical Formulas

Name each of the following chemical compounds (make sure you use the right naming

scheme!) and determine how many atoms of each element are present:

Chemical

Compound Name

Number of Atoms for Each

Element Present

1. CaF2 calcium fluoride 1 calcium, 2 fluorine

2. Be(OH)2

3. NO2

4. Al2(SO4)3

5. NH4NO3

6. S2F2

7. Na2CO3

8. CH4

9. LiNO3

10. S2F2

11. Na3PO4

12. Si(OH)4

13. CaBr2

14. PbBr2

15. CaSO4

16. CuCO3

17. H2O

18. NaCl

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Interpreting Chemical Formulas BLM 2-6

Find out Activity p. 37

Complete the activity using the following table.

Compound

Name

Common

Use

Chemical

Formula

Number and Name of

Elements

Total Number

of Atoms

calcium

carbonate

chalkboard

chalk CaCO3(s)

sodium

phosphate

heavy duty

cleaner Na3PO4(s)

magnesium

chloride de-icing roads MgCl2(s)

monosodium

glutamate (MSG) food seasoning NaC5H8NO4(s)

hydrogen

peroxide

bleach and

disinfectant H2O2(l)

glucose sugar C6H12O6(s)

carbon dioxide fizz in pop, dry

ice CO2(g)

freon-12 refrigerator

coolant CCl2F2(g)

1. (a) What information do the subscript numbers in a chemical formula provide?

For example, what does the 2 mean in Cl2?

(b) If there is no subscript number, what number is understood?

2. Strychnine is an extremely poisonous compound with the chemical formula C21H22N2O2(l).

(a) How many elements are present in strychnine?

(b) What is the total number of atoms represented by this formula? Show your work.

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Pure Substances Crossword BLM 2-7

Chapter 2 Vocabulary Check

Complete the crossword using the clues provided.

Across 1. one of the most important tools for chemists

(2 words)

6. the smallest form of an element

8. These elements tend to be malleable and shiny.

10. A pure substance that contains two or more

elements.

12. played cards with the elements to develop a

periodic table

13. elements found on the right side of the periodic

table

15. There is one atom of this element in every

particle of water (H2O).

16. This title describes a person who tried to make

gold from lead.

18. an element short form that is the same in every

language (2 words)

20. shorthand that describes a chemical (2 words)

21. vertical columns of the periodic table

Down 1. rows in the periodic table

2. association that standardized element symbols

and chemical names

3. process that can separate elements from

compounds (2 words)

4. simplest form of a pure substance

5. He discovered phosphorous.

7. process used to plate metal onto a substance

9. This element is found in pop cans and baseball

bats.

11. This gas makes balloons float.

14. This property describes shine.

17. This poisonous metal is a liquid at room

temperature.

19. an element that gives plumbers their title

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Chapter 2 Review Questions

1) Describe how the modern periodic table is organized. (2.1)

2) What does the staircase line in the periodic table separate? (2.1)

3) List the common properties of metals and non-metals. (2.1)

4) Name four parts of the periodic table. (2.1)

5) What information is found in each cell of the periodic table? (2.1)

6) Explain the relationship between a particle and an atom. (2.1)

7) What can a decomposition reaction tell you about a substance? (2.2)

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8) Explain the difference between an element and a compound. (2.2)

9) Describe two clues that would tell you whether a substance is an element or a

compound. (2.2)

10) What is the symbol for bohrium in German, French, and Chinese? (2.3)

11) List six chemicals you may find in your home or at school. (2.3)

12) Name and write the formula for five common compounds. (2.3)

13) What do the letters and numbers in a chemical formula tell you? (2.3)

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Complete Chapter 2 Review Questions – p. 38 #1-14

Please record your answers below or on an attached sheet of loose leaf.