ChemPhys Unit 1: Matter

1. Chemistry & Physics
UNIT 1: MATTER

2. Some rules
• Listen when others are talking
• Show respect for other opinions
• If you don’t understand, don’t hesitate to ask (raise hand)
• No cellphones in the class room
• Full participation is asked

3. Chemistry
Matter
Atoms
Periodic table
Chemical bonding
Chemical reaction
Electrolytes
Hydrocarbons
Organic chemistry

4. Physics
Gases
Liquids
Solutions
Energy
HeatForce & Motion
Light & Vision
Sound & Hearing
Electricity

5. Course content
• Theory
– Chemistry for the Health Sciences – G.I. Sackheim & D.D. Lehman
– Applied Science for Nurses– I.M. Hofmeyr
• Practice: demonstrations in laboratory science
– Chemical reactions
– Physical processes
• Tests
• Assignments
• Final examination

6. Website
• http://pson-biochemphys.yurls.net/en/page/

7. Today
• Chemistry versus Physics
– Chemical and physical change
• Matter
– Mass and weight
– Units
– Conservation of mass
• States of matter
– Solid, liquid, gas
– Change of state
– Properties
• Composition of matter
– Elements, compounds, mixtures

8. Chemistry vs Physics
CHEMICAL
REACTIONS
PHYSICAL
PROCESSES

9. Chemical & physical change
• CHEMISTRY
– Change:
“Formation of new substances”
“Making/breaking atomic bonds”
– Chemical reactions
• CHEMISTRY PHYSICS
– Boiling water in a pan
• Physics: water becomes gas, but molecules are still the same
– Burning glucose in your body
• Chemistry: water and carbon dioxide are formed
– Milk became sour
• Chemistry: sour-tasting lactic acid is formed
– Dissolving sugar in hot tea
• Physics: sugar molecules dispersed in water, but molecules are still the same
• PHYSICS
– Change:
“No new substances”
“Rearrangement of molecules”
– Physical processes

10. What is matter
• Topic of today: MATTER
– Anything that occupies space
– With a specific mass (weight)
Matter that we
CANNOT see or feel
Matter that we
CAN see or feel
Sackheim’s Chemistry: Chapter 2

11. Mass vs Weight
• Daily life: Mass is referred to as Weight
• Science: Mass is not the same as Weight
– Mass = amount of matter in an object
• Constant
– Weight = force experienced by an object due to gravity
(depends on pull of gravity)
• Varies per “location”
Sackheim’s Chemistry: Chapter 1

12. Units
• SI system
– To measure quantities
– International system for units
• Fundamental units
– Length: meter (m)
– Mass: kilogram (kg)
• Or gram (1000 g = 1 kg)
– Time: seconds (s)
• Not minutes, hours, days
– Temperature: Kelvin (K)
• Absolute zero, “brrrrrrrrr”
• Not degrees Celcius (K = °C + 273)
• Derived units
– Volume: m3
• Or liter (1 m3 = 1000 L)
• Derived from length
• Units in medicine
– Length: meter (m)
– Mass: gram (g)
– Volume: liter (L)
Sackheim’s Chemistry: Chapter 1

13. Prefixes
Prefix Abbreviation Decimal
Expression
Exponential
Expression
mega M 1.000.000 106
kilo k 1.000 103
hekto h 100 102
deka da 10 101
- - 1 100
deci d 0.1 10-1
centi c 0.01 10-2
milli m 0.001 10-3
micro μ (or mc) 0.000001 10-6
nano n 0.000000001 10-9
Sackheim’s Chemistry: Chapter 1

14. Conversions
• Mass
– 1 g = 10 dg = 100 cg = 1000 mg
– 1 kg = 1000 g
• Length
– 1 m = 10 dm = 100 cm = 1000 mm
– 1 kg = 1000 m
• Volume
– 1 L = 10 dL = 100 cL = 1000 mL
– 1 kL = 1000 L = 1 m3
Sackheim’s Chemistry: Chapter 1

15. Conservation of mass
• Ancient Greek philosophy (500 BC)
– “Nothing comes from nothing”
– Early statement referring to…
• …Law of conservation of mass (1774)
– “During chemical reaction mass is neither created nor destroyed”
– Mass before reaction (reactants) = Mass after reaction (products)
Antoine Lavoisier
Sackheim’s Chemistry: Chapter 2

16. States of matter
SOLID
LIQUID
GAS

17. Solid
• Piece of gold = solid
– Definite shape
• Cannot be changed easily
– Definite volume
• Cannot be changed easily
– Particles are tightly packed (motion is restricted)
Sackheim’s Chemistry: Chapter 2
No flow

18. Liquid
• Pint of beer = liquid
– No definite shape
• Can be poured from one glass to the other
• Beer assumes shape of new glass
– Definite volume
• Volume of beer remains the same regardless of glass
– Particles close together (motion is less restricted)
Flow
Sackheim’s Chemistry: Chapter 2

19. Gas
• When finished… empty bottle of beer filled with air = gas
– No definite shape
• Gas can be transfered from one bottle to another
– No definite volume
• More air can be forced in bottle
– Particles are far from apart (motion is unrestricted)
• Low density
Sackheim’s Chemistry: Chapter 2

20. Solid, gas, liquid
• Definite shape
• Definite volume
• Particles tightly packed
• No flow possibe
• Incompressible
• Expand slightly if heated
• No definite shape
• Definite volume
• Particle close together
• Flow possible
• Incompressible
• Expand slightly if heated
• No definite shape
• No definite volume
• Particle far apart (low density)
• Compressible
• Expand greatly if heated
Sackheim’s Chemistry: Chapter 2

21. Changes of state
Sackheim’s Chemistry: Chapter 2
Physical changes
• All about change in motion of
particles
– Melting/freezing
– Evaporation/condensation
– Sublimation
• T-t diagram
– Phase changes
• Constant temperature
• Change the state: chemistry of physics?

22. Properties
• Distinguish materials: Properties
– Identification
– Sugar versus salt?
• Physical properties
– Tells what a substance is
– e.g. color, odor, taste, solubility, density, hardness, melting point
• Chemical properties
– Tells what a substance does
– e.g. reacting in air, reacting in acid, burning in flame
Sackheim’s Chemistry: Chapter 2

23. Composition of matter
ELEMENTS
COMPOUNDS
MIXTURES
PURE SUBSTANCES

24. Elements
• Building blocks of matter: Elements
– “cannot be broken down into any simpler substance”
– Classification in two groups…
• Classification
– Metals
• Conduct heat/electricity
• Shiny surface, reflect light
• High tensile strength
• Easily processable
• Solid or liquid at RT
• Elements identified by Symbols
– Abbreviation of English name
– Abbreviation of Latin name
Sackheim’s Chemistry: Chapter 2
– Nonmetals
• Do not conduct heat/electricity very well
• Not shiny, seldom reflect light
• Frequently brittle
• Not processable
• Solid, liquid or gaseous at RT

25. Elements of human life (1)
Element Symbol Function
Oxygen O Required for water and organic compounds
Carbon C Required for organic compounds
Hydrogen H Required for water and organic compounds
Nitrogen N Required for organic compounds, proteins
Sulfur S Required for organic compounds, proteins
Calcium Ca Required for bones, teeth, necessary for enzymes, nerve musle
functions, hormonal action, cellular motility, clotting of blood
Phosphorus P Required for bones, teeth, necessary for high-energy
compounds, proteins, DNA/RNA, phospholipids
Magnesium Mg Required for many enzymes, necessary for energy reactions
Sodium Na Positive extracellular ion
Potassium K Positive intracellular ion
Chlorine Cl Negative ions
Sackheim’s Chemistry: Chapter 2

26. Elements for human life (2)
Element Symbol Function
Iodine I Required for hormones
Fluorine F Required for bones, teeth, inhitor of enzymes
Iron Fe Required for hemoglobin, enzymes
Copper Cu Required for enzymes, hemoglobin, bone formation
Zinc Zn Required for enzymes, related to action of insulin, essential to
growth and reproduction, nucleic acid metabolism
Manganese Mn Required for enzymes, essential to bone structure,
reproduction, central nervous system
Cobalt Co Required for vitamin B12
Molybdenum Mo Required for enzymes, essential to purine metabolism
Chromium Cr Related to action of insulin
Selenium Se Essential for action of vitamin E
Sackheim’s Chemistry: Chapter 2

27. Compounds
• Build from elements: Compounds
– “can be broken down into simpler substances by chemical means”
• Characteristics
– Can be separated
– Homogeneous
(every piece is the same)
– Different properties compared
to substances from which they
originate
• Example: Water (H20)
– Decomposes into hydrogen and oxygen
– All water drops have same properties
– Water has different properties
compared to hydrogen and oxygen
Sackheim’s Chemistry: Chapter 2
Water
What else?

28. Law of definite proportions
• Consider a pile of sugar
– Sugar contains carbon, hydrogen and oxygen
– Two samples: both contain exact same percentage of C, H and O
– This is in example of the law of definite proportions:
”Compounds are composed of fixed ratio of elements as determined by mass”
– Sugar: Always 40% C, 7% H, 53% O
Sample 1:
- Heat teaspoon of sugar
until only carbon is left
- Amount of carbon?
Sample 2:
- Heat teaspoon of sugar
until only carbon is left
- Amount of carbon?
Sackheim’s Chemistry: Chapter 2

29. Mixtures
• Combination of substances: Mixture
– Either a combination of elements or compounds
• Characteristics (upcoming experiment)
– No definite proportion / composition (unlike compounds)
– Separated into their components by physical means
– Components retain their individual properties
• Composition
– Homogeneous
• Mixture of water and sugar:
the same composition throughout
• Sugar cannot be distinguised
anymore from the water
– Heterogeneous
• Mixture of sugar and sand:
different composition throughout
• One solid can be distinguished
from another
Sackheim’s Chemistry: Chapter 2

30. Separation of mixtures
EXPERIMENT 001
Title: Sugar with Sand
Topic: Separation by physical means
1. Composition is variable
– Add more water or sand
2. How to separate?
– Physical processes:
evaporation, filtering
3. Sugar and sand retain properties

31. Summary (1)
Matter
Pure substance
Elements
Metals Nonmetals
Compounds
Mixtures
Homogenous Heterogenous

32. Summary (2)

33. The End

34. Test your memory
A. True or False
1. Physical change is about the formation of new substances
2. Weight is the force experienced by an object due to gravity
3. Liquids have a definite shape and no definite volume
4. During a change of state, the temperature rises
5. Nitrogen and sulfur are important sources for body proteins
B. Multiple choice
1. Which of the following is a heterogenous mixture
a) The pacific ocean; b) Wine; c) Blood plasma
2. Which substance is not a compound
a) Alcohol; b) Beer; c) Water
3. Antoine Lavoisier stated
a) The law of definite proportions; b) The law of conservation of energy; c) The
law of conservation of mass