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Chemistry I Stage II Ms. Claudia Barahona Elements & compounds in our surroundings

Elements and compounds in our surroundings

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Page 1: Elements and compounds in our surroundings

Chemistry I

Stage II

Ms. Claudia Barahona

Elements & compounds

in our surroundings

Page 2: Elements and compounds in our surroundings

Stage I1

Chemical reactions in our

surroundings

Formative Objective: The student

identifies the chemical name and formula of

elements and compounds present in our

daily lives, to reflect on the effects and

importance of these substances in our

bodies and surroundings.

Elaborated by: QFB. Claudia Barahona

Page 3: Elements and compounds in our surroundings

TOPICS

Classification of elements in : metals,

nonmetals and metalloids

Classification of compounds by the number of

elements and chemical function.

Elements present in the human body and

acquisition sources.

The effects and uses of chemical compounds

in our daily lives

Elaborated by: QFB. Claudia Barahona

Page 4: Elements and compounds in our surroundings

COMPETENCES

Generic Competences:

4. Listens, interprets, and emits pertinent messages in different situations using mediums, codes and appropriate tools.

Express ideas and concepts through

Identifies the main ideas in a text or an oral speech, and deduce conclusions from them.

5. Develops innovations and proposes solutions from established methods.

Follows directions and procedures objective.

Synthesizes evidences obtained with experimentation to produce

Uses the information and communication technologies to

Disciplinary Competences:

2. The student bases opinions about the impact of science and technology in his daily life assuming ethical considerations.

10. The Student relates the symbolic expressions of a phenomenon of the sight or using scientific instruments or models.

Page 5: Elements and compounds in our surroundings

Activity 2.1

Exploring your knowledge

Page 6: Elements and compounds in our surroundings

What is an ELEMENT?

o A pure substance

composed of only one

type of atom.

o Cannot be broken

down into another

substance by chemical or

physical means.

Page 7: Elements and compounds in our surroundings

Compounds

A pure substance consisting of 2 or more elements chemically combined, in a definite composition that can be broken down into a simpler substance, using chemical methods of separation.

Chemical methods:

◦ Electrolysis

◦ REDOX reactions

◦ Catalysis

Page 8: Elements and compounds in our surroundings

Dmitri Mendeleev (1869)

http://www.chem.msu.su/eng/misc/mendeleev/welcome.html

The periodic table

Arrangement of elements by increasing

atomic number

Page 9: Elements and compounds in our surroundings

http://www.chem.msu.su/eng/misc/mendeleev/welcome.html

K

Au

P

Sn

Cu Ni

Pb

N

Act 2.1 Q 4

Page 10: Elements and compounds in our surroundings

Representative

elements

Transition

Metals

Page 11: Elements and compounds in our surroundings

Chemical Symbols

Are one or two-letter abbreviations for the

names of an element.

ONLY THE FIRST LETTER IS CAPITALIZED.

If the symbol has a second letter, it is lowercase

SO THAT WE KNOW WHEN A DIFFERENT

ELEMENT IS INDICATED.

CO Co

CARBON MONOXIDE Cobalt

The symbol of Carbon is C, the symbol of sulfur

S. However the symbol of Cesium is Cs not CS.

Why not?

Page 12: Elements and compounds in our surroundings

Origin of some of the elements

name

Most of the chemical symbols use

letters from the current name, some

are derived from their ancient name.

Other elements are named after

planets, mythological figures, colors,

minerals, geographical location and

famous people.

Act 2.1

Part II

Page 13: Elements and compounds in our surroundings

Activity 2.2 Acquisition of knowledge

Vocabulary terms

Page 14: Elements and compounds in our surroundings

Vocabulary terms

1. Periodic table

2. Period

3. Group or family

4. Chemical symbols

5. Representative elements

6. Transition elements

7. Metals

8. Nonmetals

9. Metalloids

10. Malleable

11. Ductile

12. Element

13. Compound

14. Binary compound

15. Ternary compound

16. Polyatomic compound

17. Acids

18. Bases

19. Oxides

20. Salts

21. Valence electrons

22. Ionic bond

23. Covalent bond

Page 17: Elements and compounds in our surroundings

Typical amounts of essential

elements in:

Planet

Universe

Page 18: Elements and compounds in our surroundings

Act 2.2 Part III Element Real case

intoxication

(lethal dose)

Source of acquisition Symptoms First aid in case of

intoxication

Arsenic (As)

Can be administered

through oral via such as

food, drinks, etc.

In adults is estimated to

be 70 to 200 mg or

1 mg/kg/day.

Headaches,

confusion,

severe diarrhea,

drowsiness.

Convulsions.

vomiting, blood

in the urine,

cramping

muscles, hair

loss, stomach

pain, and more

convulsions. The

final result of

arsenic

poisoning is

coma and

death.

Dimercaproland dimer

captosuccinic

acid are chelating

agents that sequester

the arsenic away from

blood proteins.

Page 19: Elements and compounds in our surroundings

Act 2.2 Part III

Element Real case

intoxication

(lethal dose)

Source of acquisition Symptoms First aid in case of

intoxication

Chromium (Cr)

Drinking water,

Ranges between 1900

and 3300 µg/kg.

Chromate dye company.

Cr often used to

manufacture, amongst

other things, leather

products, paints, cement,

mortar and anti-

corrosives.

Can lead

to DNA

damage. After it

reaches the

blood stream, it

damages

kidneys, liver

and blood cells,

Hemolysis, rena

l and liver

failure are the

results of these

damages.

Appropriate supportive

measures may include

ventilatory support,

cardiovascular support,

and renal and hepatic

function monitoring.

Check the 7 diatomic molecules

Page 20: Elements and compounds in our surroundings

Act 2.2 Part III Element Real case

intoxication

(lethal dose)

Source of acquisition Symptoms First aid in case of

intoxication

Mercury

Consumption of fish is

by far the most

significant source of

ingestion-related

mercury exposure in

humans and animals,

although plants and

livestock also contain

mercury due

to bioconcentration of

mercury from seawater,

freshwater, marine and

lacustrine sediments,

soils.

Sensory

impairment

(vision, hearing,

speech),

disturbed

sensation and a

lack of

coordination.

Damage to the

brain, kidneys

and lungs

Immediate chelation

therapy,

Check the 7 diatomic molecules

Page 21: Elements and compounds in our surroundings

The Periodic Table

A map of the building block of matter.

1IA

18VIIIA

11H

1.00797

2IIA

Periodic Table 13IIIA

14IVA

15VA

16VIA

17VIIA

2He

4.0026

23

Li6.939

4Be

9.0122

5B

10.811

6C

12.0112

7N

14.0067

8O

15.9994

9F

18.9984

10Ne

20.179

311

Na22.9898

12Mg24.305

3IIIB

4IVB

5VB

6VIB

7VIIB

8 9VIIIB

10 11IB

12IIB

13Al

26.9815

14Si

28.086

15P

30.9738

16S

32.064

17Cl

35.453

18Ar

39.948

419K

39.102

20Ca40.08

21Sc

44.956

22Ti

47.90

23V

50.942

24Cr

51.996

25Mn

54.9380

26Fe

55.847

27Co

58.9332

28Ni58.71

29Cu63.54

30Zn65.37

31Ga65.37

32Ge72.59

33As

74.9216

34Se78.96

35Br

79.909

36Kr83.80

537

Rb85.47

38Sr87.62

39Y

88.905

40Zr91.22

41Nb

92.906

42Mo95.94

43Tc[99]

44Ru

101.07

45Rh

102.905

46Pd106.4

47Ag

107.870

48Cd

112.40

49In

114.82

50Sn

118.69

51Sb

121.75

52Te

127.60

53I

126.904

54Xe

131.30

655Cs

132.905

56Ba

137.34

57La

138.91

72Hf

178.49

73Ta

180.948

74W

183.85

75Re186.2

76Os190.2

77Ir

192.2

78Pt

195.09

79Au

196.967

80Hg200.59

81Tl

204.37

82Pb

207.19

83Bi

208.980

84Po[210]

85At[210]

86Rn[222]

787Fr[223]

88Ra[226]

89Ac[227]

104Ku[260]

105 106 107 108 109http://www.chemsoc.org/viselements/pages/periodic_table.html

Page 22: Elements and compounds in our surroundings

Reading the Periodic Table: Classification

Nonmetals, Metals, Metalloids, Noble gases

Page 23: Elements and compounds in our surroundings

Across the Periodic Table Periods: Are arranged horizontally across the

periodic table (rows 1-7) These elements have the same number of valence shells.

1IA

18VIIIA

12

IIA13

IIIA14

IVA15VA

16VIA

17VIIA

2

33

IIIB4

IVB5

VB6

VIB7

VIIB8 9

VIIIB10 11

IB12IIB

4

5

6

7

2nd Period

6th Period

Page 24: Elements and compounds in our surroundings

Down the Periodic Table Family: Are arranged vertically down the periodic table (columns or group, 1- 18 or 1-8 A,B)

These elements have the same number electrons in the outer most shells, the valence shell.

1IA

18VIIIA

12

IIA13

IIIA14

IVA15VA

16VIA

17VIIA

2

33

IIIB4

IVB5

VB6

VIB7

VIIB8 9

VIIIB10 11

IB12IIB

4

5

6

7

Alkali Family:

1 e- in the valence shell

Halogen Family:

7 e- in the valence shell

Page 25: Elements and compounds in our surroundings

Infamous Families of the Periodic Table

Notable families of the Periodic Table and some important members:

1IA

18VIIIA

12

IIA13

IIIA14

IVA15VA

16VIA

17VIIA

2

33

IIIB4

IVB5

VB6

VIB7

VIIB8 9

VIIIB10 11

IB12IIB

4

5

6

7

Alkali

Alkaline

(earth)

Transition Metals

Noble Gas Halogen

Chalcogens

Page 26: Elements and compounds in our surroundings

Classification of Elements

Page 27: Elements and compounds in our surroundings

Metals

Page 28: Elements and compounds in our surroundings

Metals appear to the left of the dark ziz-zag line

on the periodic table. Most metals are solid at room temperature.

Properties of metals

Page 29: Elements and compounds in our surroundings

Metals have

luster. This

means they are

shiny

Properties of metals

Page 30: Elements and compounds in our surroundings

Ductile metals can be

drawn into wire.

COPPER

Properties of metals

Page 31: Elements and compounds in our surroundings

Malleable

metals can

be hammered

into sheets

ALUMINUM

Properties of metals

Page 32: Elements and compounds in our surroundings

Metals have a high melting point. They

are also very dense.

Properties of metals

Page 33: Elements and compounds in our surroundings

Conductors

Metals are

good

conductors of electricity and

heat

Properties of metals

Page 34: Elements and compounds in our surroundings

A chemical property

of metal is its

reaction with

water and oxygen.

This results in

corrosion and

rust.

Properties of metals

Page 35: Elements and compounds in our surroundings

Properties of metals

• Shiny

• Solids at room T° (except Hg)

• Luster

• Good conductors of heat and electricity

• Malleable (sheet)

• Ductile (wires)

• High melting points

• High density

Page 36: Elements and compounds in our surroundings

Non-metals

Page 37: Elements and compounds in our surroundings

Nonmetals occur to the right of the dark zig-zag on the periodic table. Although Hydrogen is in family 1, it

is also a nonmetal. Many nonmetals are gases at room temperature.

Properties of Non metals

Page 38: Elements and compounds in our surroundings

Nonmetals do

not have

luster; they are dull.

Properties of Non-metals

Page 39: Elements and compounds in our surroundings

Brittle Nonmetals are

brittle so they

break easily. This means nonmetals ARE NOT ductile or

malleable.

Properties of Non-metals

Page 40: Elements and compounds in our surroundings

Nonmetals

have low

density.

Properties of Non-metals

Page 41: Elements and compounds in our surroundings

They also have a low melting point. This is why they are poor conductors of

heat and electricity.

Properties of Non-metals

Page 42: Elements and compounds in our surroundings

Properties of nonmetals

Nonmetals:

Lacks of luster

Low melting point

Low density

Bad conductors of heat or electricity

Page 43: Elements and compounds in our surroundings

Metalloids

Page 44: Elements and compounds in our surroundings

Metalloids can be found clustered around the

dark zig-zag line that separates metals and

nonmetals.

Properties of Metalloids

Page 45: Elements and compounds in our surroundings

Metalloids (metal-

like) have

properties of both

metals and

nonmetals.

Properties of Metalloids

Page 46: Elements and compounds in our surroundings

Metalloids are solids

that can be

shiny or dull.

Properties of Metalloids

Page 47: Elements and compounds in our surroundings

They conduct

electricity and

heat better than

nonmetals but not

as well as metals.

Properties of Metalloids

Page 48: Elements and compounds in our surroundings

Properties of Metalloids

Metalloids are

malleable and

ductile

Page 49: Elements and compounds in our surroundings

Properties of metals, nonmetals and

metalloids Metalloids:

Possess characteristics of both metals and

nonmetals

Semiconductors

Page 50: Elements and compounds in our surroundings

Summary

Page 51: Elements and compounds in our surroundings

What is a COMPOUND?

o A substance in

which two or

more different

elements are

CHEMICALLY

bonded together.

Page 52: Elements and compounds in our surroundings

Types of Compounds

• A compound with 2 different elements

• NaCl – Sodium Chloride Binary

• A compound with 3 different elements

• HClO Hypochlorous Acid Ternary

• A compound with 3 or more elements

• NaHCO3 Sodium Bicarbonate

Polyatomic

Page 53: Elements and compounds in our surroundings

Classification of Inorganic

Compounds

INORGANIC

COMPOUND

CLASSIFICATION

ELEMENTS Metal

Non-metals

Metalloids

COMPOUND Salt

Oxide

Base

Acid

Others*

Page 54: Elements and compounds in our surroundings

ACIDS

Contain the H+ ion and a non-metal ion or

polyatomic ion in an aqueous (aq) solution

CATION ANION

HCl -> Hydrochloric acid

H2SO4 -> Sulfuric acid

Some characteristics

Taste Sour

Feel May Sting

Litmus Red

Phenolphthalein Colorless

Neutralization Neutralizes bases

Page 55: Elements and compounds in our surroundings

Strong acids

6 common strong acids:

• Perchloric acid

HClO4

• Sulfuric acid

H2SO4

• Hydroiodic acid

HI

• Hydrobromic acid

HBr

• Hydrochloric acid

HCl

• Nitric acid

HNO3

Page 56: Elements and compounds in our surroundings

BASES

Contain a metal ion and the (OH)- ion in an

aqueous (aq) solution

CATION ANION

Characteristics of bases

Taste Bitter, chalky

Feel Soapy, slippery

Litmus Blue

Phenolphthalein Pink

Neutralization Neutralizes acids

No special naming rules for bases.

Ex. KOH -> potassium hydroxide

Ex. NH4OH -> ammonium hydroxide

Page 57: Elements and compounds in our surroundings

OXIDES

Binary compounds that contain a metal or

non metal ion and the O-2 ion, normally in a

solid state (s)

Al2O3 is aluminum oxide ( Ionic M-NM)

CO carbon monoxide (Covalent NM-NM)

Page 58: Elements and compounds in our surroundings

SALTS

Contain a metal ion (Not H+) and non-metal ion or

polyatomic ion (NOT (OH)- nor, O-2 )

1. normally in a solid state, (s), or in an aqueous, (aq),

solution

2. SALTS ARE FORMED AFTER THE NEUTRALIZATION

OF AN ACID BY A BASE

Example:

LiF lithium fluoride

MgCr2O7 magnesium dichromate

Pb(ClO3)4 lead (IV) chlorite

CATION ANION

Page 59: Elements and compounds in our surroundings

Others

Ionic compounds

Covalent compounds

Page 60: Elements and compounds in our surroundings

Ionic compounds

Ions are held together by strong electrical attractions between the opposite charges called ionic bonds. ◦ Cation= Metal

◦ Anion= Nonmetal

The sum of the ionic charges

on the formula is always

zero!!

CATION ANION

Page 61: Elements and compounds in our surroundings

Covalent compounds

Forms when atoms of 2 nonmetals share electrons.

Held together by the sharing of electrons called covalent bond.

When 2 or ore atoms share electrons they form a molecule.

CATION ANION

Page 62: Elements and compounds in our surroundings

Review

Classify the following compounds based on the number of elements and function.

1. AgOH

2. MgO

3. KOH

4. CaF2

5. Na2CO3

6. Na3PO4

7. CaCO3

8. H2SO4

9. ClO3

10. SO3

11. Fe203

12. Mg(OH)2

13. HNO3

14. PbO2

15. CO2

16. Na2O

17. HBr

Page 63: Elements and compounds in our surroundings

Activity 2.4

Check

Page 64: Elements and compounds in our surroundings

Elements in their natural state

Simplest kind of pure substance that contains only one

type of matter and cannot be broken down by chemical

methods.

Most of the elements in their natural state are

found as compounds.

Diatomic molecules

7 elements are found as diatomic molecules:

◦ H2, N2, O2, F2, Cl2, Br2 e I2

Elaborated by: QFB. Claudia Barahona

Page 65: Elements and compounds in our surroundings

Chemical compounds by

number of

elements

Elaborated by: QFB. Claudia Barahona

Page 66: Elements and compounds in our surroundings

Compounds

Two or more elements chemically combined.

Elaborated by: QFB. Claudia Barahona

Page 67: Elements and compounds in our surroundings

Number of elements

Compounds can be classified according to

the number of different elements

chemically combined as:

◦ Binary (two elements)

Ex: NaCl, FeS, H2O.

◦ Ternary (Three elements)

Ex: NaOH, HClO4, H2SO4

◦ Polyatomic (four or more)

Ex: NaHCO3, (NH4)2SO4, NaHSO3

Elaborated by: QFB. Claudia Barahona

Page 68: Elements and compounds in our surroundings

Classification of compounds by their

function

compounds

Acids Bases Oxides Salts

Elaborated by: QFB. Claudia Barahona

Page 70: Elements and compounds in our surroundings

Acids

Arrhenius theory: Substance that dissolves in

water and produces hydrogen ions (H+).

Bronsted-Lowry: Proton donor substances.

Elaborated by: QFB. Claudia Barahona

Page 71: Elements and compounds in our surroundings

Properties of Acids

Sour taste.

Turns litmus paper indicator red.

Turns phenolphtalein indicator colorless.

Corrode some metals.

Elaborated by: QFB. Claudia Barahona

Page 72: Elements and compounds in our surroundings

Bases

Arrhenius theory: Substance that dissolves in

water and produces hydroxide ions (OH-).

Bronsted-Lowry: Proton acceptor substances.

Elaborated by: QFB. Claudia Barahona

Page 73: Elements and compounds in our surroundings

Properties of Bases

Bitter taste.

Slippery feel (soaps).

Turns litmus indicator blue.

Turns phenolfphtalein indicator pink.

Elaborated by: QFB. Claudia Barahona

Page 74: Elements and compounds in our surroundings

Oxides

Chemical binary compounds with one or

more oxygen atoms combined with another

element.

Elaborated by: QFB. Claudia Barahona

Page 75: Elements and compounds in our surroundings

Salts

Ionic compound that contains a metal ion or

NH4+ and a nonmetal or polyatomic ion

other than OH-.

Elaborated by: QFB. Claudia Barahona

Page 76: Elements and compounds in our surroundings

Chemical compounds by

type of bond

Elaborated by: QFB. Claudia Barahona

Page 77: Elements and compounds in our surroundings

Ionic compounds

Consists of positive ion (metal) and negative ion

(nonmetal).

Metal - Nonmetal

Ions are held together by strong electrical

attractions between the opposite charges called

ionic bonds.

Elaborated by: QFB. Claudia Barahona

Page 78: Elements and compounds in our surroundings

Covalent compounds

Forms when atoms of 2 nonmetals share

electrons.

Nonmetal – Nonmetal

Held together by the sharing of electrons called

covalent bond.

When 2 or more atoms share electrons they

form a molecule.

Elaborated by: QFB. Claudia Barahona

Page 79: Elements and compounds in our surroundings

Electronegativity

Relative ability of an atom to attract the

share electrons by itself.

In a period, it increases.

In a group it decreases.

Nonmetals, Fluorine 4.0 and oxygen 3.5

have the highest electronegativites.

Metals Cesium and Francium have the

lowest electronegativities.

Elaborated by: QFB. Claudia Barahona

Page 80: Elements and compounds in our surroundings

Electronegativity

Increasing electronegativity

Incr

eas

ing

ele

ctro

ne

gati

vity

Representative

elements

Transition

Metals

Elaborated by: QFB. Claudia Barahona

Page 81: Elements and compounds in our surroundings

Polarity

• Describes how electrons are shared between

atoms .

• Electrons are not always shared equally

between two bonding atoms.

• One atom might exert more of a force on the

electron than the other, electronegativity.

• The unequal sharing of electrons within a bond

leads to the formation of polarity.

Elaborated by: QFB. Claudia Barahona

Page 82: Elements and compounds in our surroundings

Polarity of bonds

Nonpolar covalent bond: Bond between

atoms with identical or very similar

electronegativities.

Elaborated by: QFB. Claudia Barahona

Page 83: Elements and compounds in our surroundings

Polarity of bonds

Polar covalent bond: Electrons are shared

unequally.

Elaborated by: QFB. Claudia Barahona

Page 84: Elements and compounds in our surroundings

Summary of bonds

Elaborated by: QFB. Claudia Barahona

Page 85: Elements and compounds in our surroundings

Topic: Chemical elements and compounds in your body and surroundings

Compound Formula Elements

involved

Classificatio

n by # of E

Classification

by chemical

function

Carbon dioxide CO2 Carbon

Oxygen

Binary Oxide

Hydrochloric acid HCl Hydrogen

Chlorine

Binary Acid

Vinegar (Acetic

acid)

CH3(COOH) Carbon

Hydrogen

Oxygen

Ternary Acid

Table salt

(sodium chloride)

NaCl Sodium

Chlorine

Binary Salt

Elaborated by: QFB. Claudia Barahona

Page 86: Elements and compounds in our surroundings

Topic: Chemical elements and compounds in your body and surroundings

Compound Formula Elements

involved

Classificatio

n by # of E

Classification

by chemical

function

Sodium

bicarbonate

NaHCO3 Sodium

Hydrogen

Carbon

Oxygen

Polyatomic Salt

Sodium hydroxide NaOH Sodium

Oxygen

Hydrogen

Ternary Base

Calcium oxide CaO Calcium

Oxygen

Binary Oxide

Nitrogen

monoxide

NO Nitrogen

Oxygen

Binary Oxide

Elaborated by: QFB. Claudia Barahona

Page 87: Elements and compounds in our surroundings

1. An ionic compound is a chemical compound in

which ions are held together by the electrostatic

force between oppositely charged ions.

2. An ionic compound is form by a positively charge ion

called a cation, which is always a metal and a

negatively charged ion called a anion which is always

a nonmetal or a polyatomic ion when we have 2

or more nonmetals together with a charge.

Elaborated by: QFB. Claudia Barahona

Page 88: Elements and compounds in our surroundings

3. The main difference between ionic and covalent

compounds is that ionic compounds is composed of

a metal bonded to a nonmetal while a covalent

compound is a nonmetal bonded to a nonmetal.

4. In ionic compounds there is a complete

transference of electrons.

5. In covalent compounds electrons are being shared.

Elaborated by: QFB. Claudia Barahona

Page 89: Elements and compounds in our surroundings

Compound Classification Compound Classification

BaCl2 Ionic Cl2O covalent

N2O4 Covalent KF Ionic

Elaborated by: QFB. Claudia Barahona

Page 90: Elements and compounds in our surroundings

Compounds according to the type of

bond

Elaborated by: QFB. Claudia Barahona

Page 91: Elements and compounds in our surroundings

Ionic compounds

Consists of positive ion (metal) and negative ion

(nonmetal).

Ions are held together by strong electrical

attractions between the opposite charges called

ionic bonds.

Elaborated by: QFB. Claudia Barahona

Page 92: Elements and compounds in our surroundings

Covalent compounds

Forms when atoms of 2 nonmetals share

electrons.

Held together by the sharing of electrons called

covalent bond.

When 2 or more atoms share electrons they

form a molecule.

Elaborated by: QFB. Claudia Barahona

Page 93: Elements and compounds in our surroundings

Metallic bonds

Bonding of atoms in solid metallic

crystals.

A three-dimensional array of positive ions

that remain fixed in the crystal lattice

while loosely held valence electrons move

freely throughuot the crystal.

Sharing a “sea of ve-”.

e- are free to move.

Elaborated by: QFB. Claudia Barahona

Page 94: Elements and compounds in our surroundings

Properties

Good conductors of electricity and heat

Insoluble in water

Malleable (sheets)

Ductile (wires)

Shiny

Elaborated by: QFB. Claudia Barahona

Page 95: Elements and compounds in our surroundings

END OF STAGE 2