1. Introduction to Chemistry Ms. Argenzio

2. What is Chemistry?
Chemistry: The study of the composition and structure of matter, the properties of matter, and the energy involved in changing matter.

3. Matter: anything that has mass takes up space (volume)
What is matter?
Matter: anything that has mass takes up space (volume)
Homogeneous: matter which has a uniform composition throughout
Heterogeneous: matter which has a non-uniform composition throughout

4. Definitions
Composition: what type of atoms/molecules make up a sample of matter Structure: how the atoms are arranged in a sample of matter Properties: physical (descriptive) & chemical (behavioral) characteristics of matter

5. Properties
Extensive Properties: -depend upon amount -examples include mass and volume
Intensive Properties: do not depend upon amount
-examples include density, melting point, boiling point

7. Structure of Matter
Pure Substances:
A specific type of matter with its
own composition, structure, and
properties
Includes both elements and compounds
Elements:
Simplest building blocks of matter
Composed of only one type of atom
Cannot be broken down by ordinary chemical change

8. Compounds:
Two or more elements chemically combined in a constant(fixed) ratio by mass
Usually composed of molecules or ions
Can be decomposed chemically

9. Two or more substances physically combined
Mixtures
Mixtures:
Two or more substances physically combined
Composed of more than one type of particle
Ratios by mass may vary

11. Law of Conservation of Matter:
Atoms can not be created nor destroyed during chemical or physical changes. The atoms are just rearranged. (The total number and type of atoms in the universe is constant)

12. LAW OF CONSERVATION OF MATTER QUESTIONS
1) Given the following reaction
2Na(l) + Cl2(g) 2NaCl (l)
a) Identify the reactant(s)___________________________
b) Identify the product(s)___________________________
c) A 460. gram sample of Na(l) reacts with a 710.g sample of Cl2(g). What is the total mass of NaCl(l) produced.

13. 2) Given the following reaction
Example 2
2) Given the following reaction
2NaHCO3 (s) + heat Na2CO3(s) + H2O(g) + CO2 (g)
Determine the total mass of sodium carbonate produced if kilograms of NaHCO3 reacts completely to produce 360. kilograms of H2O and 880. kilograms of CO2?

14. Problem 3
3) In an experiment, 2.54 grams of copper completely reacts with sulfur, producing grams of copper(I)sulfide. Determine the total mass of sulfur consumed.

15. Changes
Chemical Changes: Involves the rearrangement of the particles of matter to produce a new substance of new chemical composition. Signs of a chemical change (chemical reaction) include Color/Odor change Production of gas/solid product Energy (Heat/Light) Not easily reversed

16. Physical Changes: Changes the appearance of the sample of matter but not its identity (composition). Examples include changes in size, shape or phase.

17. Density
Density – mass per unit of volume
Formula on Table T in reference tables
Density = Mass
Volume
Element densities can be found on Table S

18. Example 1
What is the density of a 2cm x 3cm x 4cm aluminum block with a mass of 64.8g?

19. What is the volume (in cubic centimeters) of a 10.0g block of gold?
Example 2
What is the volume (in cubic centimeters) of a 10.0g block of gold?

20. Separating Mixtures

21. ...how could you separate this mixture?
Separating Mixtures
Mixing sulphur and iron...
...how could you separate this mixture?

22. Separating Mixtures

23. Do not put magnetic directly on iron
Hold the magnet below the Petri dish
Sulphur + Iron mixture
Petri dish
Magnet

24. Separating Mixtures: Filtration – separating an insoluble solid from a solution
filter paper
Mixture (salt, sand, water)
filter funnel
Mixture (salt and water)

25. Separating Mixtures: Evaporation – separating a soluble solid from a solution
Water
Evaporating dish
Mixture (salt and water)
Bunsen burner

26. Separating Mixtures: Distillation – separating 2 soluble substances based on boiling points
What is happening here?
Water Vapour
Mixture (salt and water)
Bunsen burner
Water

27. Separating Mixtures
You’re stranded on a desert island surrounded by sea water, sadly your science teacher is lost at sea but luckily all your science equipment has washed up...
...how could you separate a mixture of sand, salt and water to get drinking water?

28. Goal: to extract clean fresh water
Come up with a plan, you will need:
A list of equipment
A series of steps
You should be able to explain your reasoning for each step, use your science knowledge!