Chapter 1: Introduction to Chemistry

Chemistry: the study of matter and the changes it undergoes

Matter: anything that has mass and takes up space

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??? What is not matter?

??? What causes matter to change forms?

Substance: also known as a chemical, must have definite and uniform composition

Mass vs. Weight

-Mass-

-Weight-

??? Why would scientists use mass instead of weight?

Model: a visual, verbal, or mathematical explanation of experimental data. Used to represent things that are hard to visualize

Scientific Method: an organized, systematic process used in scientific study

Observation: an act of gathering information

Qualitative data/observations:

Quantitative data/observations:

???? Give an example of each.

Hypothesis: tentative explanation of observations

Experiment: set of controlled observations to test a hypothesis

Independent variable:

Dependent variable:

Control group:

Experimental group:

??? You are asked to determine the effect of temperature on the volume of a balloon. The balloon's size increases as it is warmed. Identify the previous parts of the experiment

Conclusion: judgment based on the information obtained

Theory: explanation of natural phenomenon based on many observations and investigations over time

Scientific Law: a relationship in nature that is supported by many experiments.

Safety rules: http://nobel.scas.bcit.ca/debeck_pt/science/safety.htm

Lab equipment: http://paulabrown.net/chemistry-laboratory-equipment-212.png

Lab equipment quiz: http://www.proprofs.com/quiz-school/story.php?title=laboratory-equipment you must pass with an 85%, the password is chemistry, print the certificate as proof and send to Ms. Murphy by _____________________.

Chapter 2 Analyzing Data

Base Unit: defined unit in a system of measurement that is based on an object of event in the physical world. It is independent of other units

Time:

Length:

Mass:

Temp:

Amount of a substance:

Derived units: defined by a combination of base units

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Measurements in science activity

Importance of density:

High vs Low density visual:

Density of Water:

Density practice problems

1) 22.5 mL of mercury metal is poured into a graduated cylinder. The empty graduated cylinder has a mass of 23.0 g and the cylinder with the mercury has a mass of 306.0 g. From this information, calculate the density of mercury.

2) What is the mass of the ethyl alcohol that exactly fills a 200.0 mL container? The density of ethyl alcohol is 0.789 g/mL.

3) A rectangular block of copper metal weighs 1896 g. The dimensions of the block are 8.4 cm by 5.5 cm by 4.6 cm. From this data, what is the density of copper?

4) A 2.0 g object is placed in a graduated cylinder with 12.0 mL of water and causes the water to rise to 15.0 mL. What is the density of the water?

DENSITY LAB

Scientific Notation: used to express any number as a number between 1 and 10 multiplied by 10 raised to a power.

Putting numbers into sci notation:

Taking numbers out of sci notation:

Correcting the format of numbers in sci notation:

Adding/Subtracting numbers in sci notation:

Multiplying/Dividing numbers in sci notation:

Metric Conversions and Dimensional Analysis

https://www.youtube.com/watch?v=9O2Keu6o3i0 measuring the length of a microwave with a chocolate bar

Metric Conversion and Dimensional Analysis Practice Problems

Accuracy: refers to how close a measured value is to an accepted value.

Precision: refers to how close a series of measurements are to one another.

Visual:

Calculating Percent Error:

1. A student was told that the mass of a sample of matter was 2.34 g when it was actually 2.32 g. What was the percent error?

Significant Figures: include all known digits plus one estimated digit.

Significant figure rules:

1. All nonzero digits are significant

2. Leading zeros are never significant (they are place holders)

3. Captive zeros are always significant.

4. Trailing zeros are significant if they trail both a number and a decimal

Practice identifying significant figures: https://www.khanacademy.org/math/pre-algebra/decimals-pre-alg/sig-figs-pre-alg/e/significant_figures_1

Significant Figures and Math

Adding/Subtracting: your answer should have as many digits after the decimal as the value with the least number of digits after the decimal.

Multiplying/ Dividing: your answer should have as many digits after the decimal as the value with the least number of significant digits.

Multiple step math problems and sig figs: (don't round until the end and we will all have the same answers!

Sig figs and calculations word problems: http://www.sciencegeek.net/APchemistry/APtaters/sigfigs.htm

Chapter 3: Matter: Changes and Properties

Properties of Matter

Physical properties: a characteristic that can be observed or measured without changing the sample's composition.

Extensive physical properties: are dependent on the amount of substance present

Examples:

Intensive physical properties: are independent on the amount of substance present

Examples:

Insert picture of matter: identify properties

Chemical properties: the ability of a substance to combine with or change into one or more other substances

QUICK DEMO page 74

Changes in Matter

Physical changes: a change which alters a substance without changing its composition

Phase changes:

Chemical changes: a process that involves one or more substances changing into new substances; these are commonly referred to as chemical reactions

https://www.youtube.com/watch?v=0Bt6RPP2ANI

Evidence of chemical reactions:

It is important to realize that the products of chemical reaction have very different properties than the reactants that formed them.

A + B —≥ AB

sodium + chlorine —≥ sodium chloride

Law of Conservation of Mass – mass is neither created not destroyed during a physical or chemical change.

mass reactants = mass products

Substance Before Reaction After ReactionAluminum 10.3 g 0.0 gLiquid bromine 100.0 g 8.5 gCompound 0.0 g ?

1. How is an OPEN system different from a CLOSED system?

2. Explain a situation in which the reactants might appear to weigh more than the products. (note: this is actually impossible!)

3. Answer the word problems below using the LAW OF CONSERVATION OF MASS.

a) Hydrogen and oxygen react chemically to form water. How much water would form if 14.8 grams of hydrogen reacted with 34.8 grams of oxygen? (H2 + O2 H2O)

b) When ammonium nitrate (NH4NO3) explodes, the products are nitrogen, oxygen, and water. When 40.0 grams of ammonium nitrate explode, 14.0 grams of nitrogen and 8.0 grams of oxygen form. How many grams of water form? (NH4NO3 N2 + O2 + H2O)

Types of Matter

Mixtures: A combination of two or more pure substances in which each pure substance retains its individual chemical properties . Two or more substances are physically combined and therefore retain the properties of the individual components.

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Heterogeneous Mixtures: a mixture that does not blend smoothly throughout and in which the individual substances remain distinct; two or more distinct areas are always present

Homogeneous Mixtures: a mixture that has constant composition throughout; it always has a single phase

Solutions: homogeneous mixtures are referred to as solutions

Mixtures are physically combined and therefore can be separated by physical means.

Filtration: a technique that uses a porous barrier to separate a solid from a liquid.

Distillation: a separation technique that is based on difference in the boiling points of the substances

involved.

Crystallization: a separation technique that results in the formation solid particles of a substance from a solution containing the dissolved substance.

Chromatography: a technique that separates the components of a mixture based on the ability of each component to travel or be drawn across the surface of another material.

Elements and Compounds

Element: pure substance that cannot be separated into simpler substances by physical or chemical means

Periodic Table: organizes the elements into a grid of horizontal rows called periods and vertical column called groups or families. Elements in the same group have similar chemical and physical properties. The table is called periodic because the pattern of similar properties repeats from period to period.

Compound: is made up of two or more elements that are combine chemically

Draw an image of an element, a molecule, a compound and a mixture, both hetero and homogeneous

Law of Definite Proportions: states that a compound is always composed of the same elements in the same proportion by mass, no matter how large or small the sample.

Percent by Mass = mass of element/mass of compound x 100

1. 5.0 grams of sugar are dissolved in 150 g of water What is the mass percent of sugar in the solution?

2. How many grams of NaBr are needed to make 50 g of a 5.0% solution?

3. What mass of NaF must be mixed with 25 mL of water to create a 3.5% by mass solution?

4. What is the percent carbon in the compound C2H3OH

Law of Multiple Proportions: states that when different compounds are formed by a combination of the same elements, different masses of one element combine with the same relative masses of the other element in a ratio of small whole numbers.

Law of multiple proportions: https://www.youtube.com/watch?v=ltPSmKW-mV4

Changes in Matter