Test Tubes General Chemistry A CH4701. This lecture: General information Course syllabus Recommended texts Relevance of this module to you

Test TubesGeneral Chemistry A CH4701

This lecture:

General information

Course syllabus

Recommended texts

Relevance of this module to you

This lecture:

General information

Course syllabus

Recommended texts

Relevance of this module to you

Topic 1:- Fundamental principles

Topic 2:- Classification of matter

Lecturer Edmond Magner MS1016 Andrew McCormack MS10

Course duration 1 semester

Lecturer Edmond Magner MS1016 Teresa Curtin MSG015


Class contact 2 x 50 min lectures/week

1 x 2 hour lab/fortnight

Assessment 60% exam, 40% labs

Lecturer Edmond Magner MS1016 Teresa Curtin MSG015


Class contact 2 x 50 min lectures/week

1 x 2 hour lab/fortnight

Assessment 60% exam, 40% labs

Labs In B3-053

MUST have white lab coat and safety specs

Your first lab session will be on week 3 (B3053)

CH 4701 COURSE SYLLABUS

1. Basics

Simple characterisation of atoms + molecules Chemical accounting: the mole Early chemical ideas & their present day uses Modern theories of atomic structure Introduction to chemical bonding The Periodic Table

CH 4701 COURSE SYLLABUS

1. Basics

Simple characterisation of atoms + molecules Chemical accounting: the mole Early chemical ideas & their present day uses Modern theories of atomic structure Introduction to chemical bonding The Periodic Table

2. Applied chemistry

Gas laws Electrochemistry Chemical equilibria (solutions and acids/bases)

TEXTS & COURSE MATERIALS

Essential for all: Good set of lecture notes!


Essential for all: Good set of lecture notes! CH4701 Course Materials Pack: - available from UL Print Room (E1-006)

reference number 3485, price €4.50


Essential for all: Good set of lecture notes! CH4701 Course Materials Pack: - available from UL Print Room (E1-006)

reference number 3485, price €5.00

Recommended for students without Leaving Cert chem: Chemistry: The Central Science 8th edn., by Brown, LeMay and Bursten

- available UL Bookshop, price ca. €38.00 (includes multimedia CD-ROM)

Some copies of other gen. chem. texts available in UL library under classification 540.

COURSE AIMS + RELEVANCE

1. "Educate"


1. "Educate"

2. Give a basic understanding of the theory, practice and everyday applications of chemistry to non- chemists


1. "Educate"


3. Review of fundamentals for chemists


1. "Educate"



CHEMISTRY


1. "Educate"



CHEMISTRY

Describes:

structure & composition of matter


1. "Educate"



CHEMISTRY

Describes:


changes in structure & composition


1. "Educate"



CHEMISTRY

Describes:


changes in structure & composition

energy involved in these changes

FUNDAMENTAL PRINCIPLES

Law of conservation of energy: "Energy can be neither created nor destroyed, but may be transformed from one form to another"



Law of conservation of mass: "Mass cannot be created or destroyed. The total mass of substances involved in a physical or chemical change remains constant"



Law of conservation of mass: "Mass cannot be created or destroyed. The total mass of substances involved in a physical or chemical change remains constant"

Special theory of relativity: E = mc2, where c = velocity

of light)

CLASSIFICATION OF MATTER

Properties of Matter



Bulk (Substantive) Particulate




Physicalstate




Physicalstate

Metallic character




Physicalstate

Metallic character

Physical appearance




Physicalstate

Metallic character

Physical appearance

Chemical integrity

Classification by physical state:

Solid (Plutonium)

Liquid (Mercury)

(Chlorine)Gas

Classification by metallic character: metal or non-metal?

Classification by metallic character: metal or non-metal?

Classification by physical appearance:

Homogeneous

Heterogeneous

(Ruby)

(Moon rock)

Classification by chemical integrity:

Matter

Mixtures


Matter

Mixtures

(Bronze) (Agate)


Matter

Pure substances Mixtures

(Bronze) (Agate)


Matter


Elements (Bronze) (Agate)

(Carbon)


Matter


Compounds

Elements (Bronze) (Agate)

(Carbon) (Ice)

Definitions.

Mixture: contains 2 or more pure substances, whichcan be separated out by physical means.

Definitions.


Pure substances: have a definite chemical compositionand properties. They cannot be separated into simplersubstances by physical means.

Definitions.



Compound: pure substance which can be further broken down by chemical means.

Definitions.



Compound: pure substance which can be further broken down by chemical means.

Element: pure substance which cannot be furtherbroken down by ordinary chemical means.

Some examples of matter classification

Steam?

• Gas, non-metallic, homogeneous, compound.


Steam?


Sugar?

• Solid, non-metallic, homogeneous, compound.


Steam?


Sugar?


Air?

• Gas, non-metallic, homogeneous, mixture.


Steam?


Sugar?


Air?


Brass?

• Solid, metallic, homogeneous, mixture.


Steam?


Sugar?


Air?


Brass?

• Solid, metallic, homogeneous, mixture.

Mars Bar?

• Solid, non-metallic, heterogeneous, mixture

Differences between mixtures and compounds

Mixture Compound

Components can be Components can not be separated by using separated by using physical techniques physical techniques


Mixture Compound


Composition is variable Composition is fixed


Mixture Compound


Composition is variable Composition is fixed

Properties are related to Properties are unlike those of its components those of its components

Table of some of the more common elements

Element SymbolHydrogen HHelium HeCarbon CAluminium Al


Element SymbolHydrogen HHelium HeCarbon CAluminium AlNitrogen NOxygen OPhosphorous PIron Fe


Element SymbolHydrogen HHelium HeCarbon CAluminium AlNitrogen NOxygen OPhosphorous PIron FeCopper CuNickel NiSulphur SIodine I

http://www.ul.ie/~ces/Resources.html

The correct classifications for sea water, distilled water, brass, and helium respectively are

(a)compound, element, mixture and compound

(b)mixture, element, mixture and compound




(c) mixture, compound, mixture and element

(d) compound, element, compound and mixture

(e) mixture, compound, compound and element













All mixtures (indicate correct statement)

(a) are heterogeneous in appearance

(b) contain different types of molecules










(c) contain two or more pure substances

(d) can be separated only by chemical means

(e) contain more than one physical state










(c) contain two or more pure substances

(d) can be separated only by chemical means

(e) contain more than one physical state

DIMENSIONS AND UNITS

Need to provide a quantitative means of describing the universe.



7 independent dimensions (physical quantities):




1. Mass (m) quantity of matter in a body





2. Length (l) measurement of distance






3. Time (t) measurement of progress of an event






3. Time (t) measurement of progress of an event

4. Thermodynamic temperature (T). “The condition of a body which determines the transfer of heat to or from that body”

DIMENSIONS AND UNITSDIMENSIONS AND UNITS

5. Amount of substance (n). “The number of specified entities of a pure substance”



6. Electric current (I): “Rate of transfer of electricity”




7. Luminous intensity (Iv): “Rate of transfer of light energy”





Fundamental Property of Dimensions:Two physical quantities having different dimensionscannot be added, subtracted or equated.






All other physical quantities can be expressed in terms of these fundamental dimensions







e.g. volume of a cube = l x l x l = l3







e.g. volume of a cube = l x l x l = l3

velocity = distance/ time = l/t

Units:

Defined value of a given dimension for reference purposes

Units:


Preferred system (in chemistry) is S.I.

Units:



Dimension S.I. Unit

Units:



Dimension S.I. Unit

Mass kg

Units:



Dimension S.I. Unit

Mass kgLength m

Units:



Dimension S.I. Unit

Mass kgLength mTime s

Units:



Dimension S.I. Unit

Mass kgLength mTime sTemperature K (kelvin)

Units:



Dimension S.I. Unit

Mass kgLength mTime sTemperature K (kelvin)Amount of substance mol (mole)

Units:



Dimension S.I. Unit

Mass kgLength mTime sTemperature K (kelvin)Amount of substance mol (mole)Current A (ampere)

Units:



Dimension S.I. Unit

Mass kgLength mTime sTemperature K (kelvin)Amount of substance mol (mole)Current A (ampere)Luminous intensity cd (candela)

Common S.I. prefixes

Prefix Name Meaning

G giga 109

M mega 106

k kilo 103


Prefix Name Meaning

G giga 109

M mega 106

k kilo 103

d deci 10-1

c centi 10-2

m milli 10-3


Prefix Name Meaning

G giga 109

M mega 106

k kilo 103

d deci 10-1

c centi 10-2

m milli 10-3

micro 10-6

n nano 10-9

p pico 10-12

Derived Units

Quantity Definition Derived Unit

Area Length x length m2

Derived Units



Volume Area x length m3

Derived Units




Density Mass/ unit volume kg m-3

Derived Units





Speed Distance/ unit time m s-1

Derived Units






Acceleration Change in speed/ m s-2

unit time

Derived Units







unit time

Force Mass x acceleration kg m s-2 (newton, N)

Derived Units







unit time


Pressure Force/ unit area kg m-1 s-2 (pascal, Pa)

Derived Units







unit time


Pressure Force/ unit area kg m-1 s-2 (pascal, Pa)

Energy Force x distance kg m2 s-2 (joule, J )

Difference between mass and amount of substance:

amount of substance is the number of specified entities (e.g. atoms, molecules, etc.)



Entity Number of entities Mass (g)

Hg 6.02 x 1023 atoms 200.59(= 1 mol)




Hg 6.02 x 1023 atoms 200.59(= 1 mol)

KCl 6.02 x 1023 molecules 74.56(= 1 mol)




Hg 6.02 x 1023 atoms 200.59(= 1 mol)

KCl 6.02 x 1023 molecules 74.56(= 1 mol)

SO42- 6.02 x 1023 ions 96.06

(=1 mol)

Accuracy: measure of how close measurement is to its real value


Precision: measure of how close successive measurements are to each other



XXX

Precise & accurate



XXXXX X

Precise Precise& accurate & inaccurate



XXXXX X

X X

X

Precise Precise Imprecise& accurate & inaccurate & inaccurate

Dimensional analysis: a method of reducing physicalquantities to combinations of the 7 basic dimensions


Q1. Dimensions of pressure?



A. Pressure = Force/Area and we already know the dimensions of force are MLt-2. Thus the dimensions of pressure are MLt-2/L2 = ML-1t-2.




Q2. Check the validity of the following equation: PV = nR/T, given units of R to be ML2t-2n-1T-1.





A. Dimensions of L.H.S.: ML-1t-2 . L3 = ML2t-2

Dimensions of R.H.S.: n . ML2t-2n-1T-1 = ML2t-2T-2





A. Dimensions of L.H.S.: ML-1t-2 . L3 = ML2t-2

Dimensions of R.H.S.: n . ML2t-2n-1T-1 = ML2t-2T-2

Equating both sides does not cancel all terms, thus equation is invalid.

ATOMS AND MOLECULES

ATOMS AND MOLECULES

Atom:smallest particle of an element which canundergo chemical changes in a reaction

ATOMS AND MOLECULES

Atom:smallest particle of an element which canundergo chemical changes in a reaction

Molecule: smallest particle of a compound which can exist and still retain the chemical properties of the compound.

Structure of the Atom


Size: 0.1 to 0.5 nanometers (1nm = 1x10-9m)



Mass: H atom = 1.67x10-24g = 1.008 atomic mass units (a.m.u.)




C atom = 2x10-23g = 12.000 a.m.u.




C atom = 2x10-23g = 12.000 a.m.u.

Electrical charge: neutral




C atom = 2x10-23g = 12.000 a.m.u.


Composition: contains electrons, protons, and, with the exception of hydrogen, neutrons.




C atom = 2x10-23g = 12.000 a.m.u.



Particle Mass (a.m.u.) Charge e- 0.0005 -1




C atom = 2x10-23g = 12.000 a.m.u.



Particle Mass (a.m.u.) Charge e- 0.0005 -1 p+ 1.007 +1




C atom = 2x10-23g = 12.000 a.m.u.



Particle Mass (a.m.u.) Charge e- 0.0005 -1 p+ 1.007 +1 n 1.009 0



Size: 0.1 to 0.5 nanometers (1 nm = 1 x 10-9 m)



Electron clouds

~ 2 x 10-10 m



Nucleus Electron clouds

~ 2 x 10-10 m




~ 5 x 10-15 m

~ 2 x 10-10 m




~ 5 x 10-15 m

~ 2 x 10-10 m

Nucleus- consists of protons and neutrons

“Life-sized” model of the atom


“Scaled up” electron mass

Electron = 0.0005 a.m.u. Proton = 1.0070 a.m.u.



Electron = 0.0005 a.m.u. Proton = 1.0070 a.m.u.“Model proton” = 65 kg “Model electron” = 32 g




“Scaled up” atomic radius

Nuclear diameter = 5 x 10-15m Atomic diameter = 2 x 10-10 m





Nuclear diameter = 5 x 10-15m Atomic diameter = 2 x 10-10 m “Model nucleus” radius = 1 m “Model atomic” radius = 40 km






Q. A speck of carbon contains ca. 1019 atoms and the diameter of a carbon atom is 1.5 x 10-10 m. If the circumference of the earth is 40,075 km, how many times around the earth would a line of single carbon atoms extend?






Q. A speck of carbon contains ca. 1019 atoms and the diameter of a carbon atom is 1.5 x 10-10 m. If the circumference of the earth is 40,075 km, how many times around the earth would a line of single carbon atoms extend?

A. Length = 1019 x 1.5 x 10-10 m = 1.5 x 109 m.

# times = 1.5 x 109/40075 x 103 = 37.4

Iron atoms on acopper crystal


Carbon monoxide molecules on platinum crystal


Xenon atoms on nickel

Carbon monoxide molecules on platinum crystal

Atomic number:number of protons in an atom. Symbol: Z

Atomic mass: mass of an atom in a.m.u. (number of protons + neutrons in an atom). Symbol: A

Atomic number:number of protons in an atom. Symbol: Z

Atomic mass: mass of an atom in a.m.u. (number of protons + neutrons in an atom). Symbol: A

Atom e- p+ n Z A (a.m.u.)

H 1 1 0 1 1.008

Li 3 3 4 3 7.016

C 6 6 6 6 12.000

U 92 92 146 92 238.05

Conventional Notation for Chemical Symbols

Cl


Cl35

17

-

2

Mass number Number and sign of charge


Cl35

17

-

2


Atomic number Number of atoms in entity


Cl35

17

-

2


Atomic number Number of atoms in entity

Examples: He42 OH- CO

32-

Ions: atoms or molecules which have gained or lost oneor more electrons

Isotopes: atoms of the same element which have different masses, i.e. different numbers of neutrons



Examples of ions: H+ H- NO3-



Examples of ions: H+ H- NO3-

Examples of isotopes: H11

H12

H31

Hydrogen

Deuterium

Tritium

Elements Compounds

Atoms Molecules

Identicalatoms

Elements Compounds

Atoms Molecules

Ions Isotopes

Identicalatoms

± e- ± n

Elements Compounds

Atoms Molecules

Ions Isotopes

Identicalatoms

± e-± n

± e- ± n

Documents

Test Tubes General Chemistry A CH4701. This lecture: General information Course syllabus Recommended texts Relevance of this module to you