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Chemistry Review
Chapter 1
- Matter: anything that has mass and takes up space.
- Chemistry: the study of the composition of matter and the changes it undergoes.
- Organic Chem: the study of all chem. Containing carbon
- Inorganic chem: the study of all chem, in general, that do not contain carbon.(non-living)
- Biochemistry: the study of the processes that take place in organisms.(muscle contraction/digestion)
- Analytical chem: the area of chem. That focuses on the composition of mater.
- Physical Chem: the area that deals with the mechanism, the rate and energy transfer that occurs when mater undergoes a change.
- Pure Chemistry: the pursuit of chemical knowledge for its own sake. (no practical use for the knowledge)
- Applied Chemistry: the research that is directed to a practical goal or application. (pure research leads to an application)
- Technology: the means by which society provides its members with things needed as desired.
- Macroscopic: objects large enough to see w/ the untrained eye.
- Microscopic: can only been seem under magnification.
- Biotechnology: applies science to the production of biological products or processes.
- Pollutant: a material found in the air, water or soil that is harmful; to other org.
- Alchemists: developed the tools and techniques for working with chemicals.
- Scientific method: a logical systematic to the solution of a scientific problem. 1) making observations
2) testing a hypothesis
3) developing theories
- hypothesis: a p proposed expiation for an observation.
- Experiment: used to test a hypothesis.
- Manipulated variable: (independent variable) changed
- Responding Variable: (dependent variable) observed through out the experiment.
- Theory: a well tested explanation for a broad set of observations.
- Scientific law: a concise statement that summarizes the results of many observations and experiments.
Chapter 2
- Volume: space occupied by an object.
- Extensive Property: depends on the amount of matter in a sample.
- Intensive Property: depends on the type of matter in a sample.
- Substance: matter that has a uniform and define composition.
- Physical property: a quality or condition of a substance that can be observed or measured w/out changing its composition. ( color, shape, size, shiny, melting point, density, and texture)
- Solid: Define shape/ volume
- Liquid: in define shape and define volume
- Gas: no define shape or volume.
- Physical Change: the composition of the material does not change. (break, melt, boil, freeze)
- Mixture: a physical blend two or more components. (heterogeneous or homogeneous)
- Solution: another name for a homogeneous mixture; uniform composition.
- Phase: used to describe any part of a sample w/ uniform composition properties. (heterogeneous=2 or more phases)
- Filtration: separates solids form liquids in a heterogeneous mixture.
- Distillation: a liquid is boiled to produce a vapor that is then condensed into a liquid. (tap water)
- Element: the simplest form of matter that has a unique set of properties.
- Compound: is a substance that contains two or more chemically combined elements in a fixed proportion.
- Chemical Change: a change that produces matter w/ a different composition than that of the original matter. 1) Change in color 2) odor 3)gas formation 4)precipitant 5) change in temp.
- Chemical property: the ability of a substance to undergo a specific chemical change. (burn, rust, rot, decompose, explode)
- Chemical Reaction: one or more substances change into one ore more new substance.
- Reactant: a substance present a the start of the chem. Reaction.
- Product: the substance produced by a chem. Reaction.
- Precipitant: a solid that settles and forms out of a liquid mixture.
- Law of Conservation of Mass: states that in any physical change or chem. Reaction, mass is conserved. Mass is neither created nor destroyed.
Chapter 3
- Accuracy: is a measurement describes how close the measurement comes to the true value
- Precision: is a measurement that depends on its reproducibility
- Experimental value: is a value measured in the lab
- Error: the difference b/t the experimental value and the accepted value
Error = experimental value - accepted value
Percent Error:
Percent Error = |error|____ x 100%
accepted value
Example:
Percent Error = |99.1*C - 100.0*C| x 100%
100.0*C
= 0.9*C
Significant Figures
- The Significant Figures in a measurement include all of the digits that are known, plus the last digit that is estimated
Measurements must always be reported in the correct number of sig. figures…
Rules:
1. every nonzero digit is significant. 34.7 & .889 = 3 sig. fig.
2. zeros appearing between nonzero digits are significant. 40.79 & 1.409 = 4 sig. fig.
3. leftmost zeros appearing in front of nonzero digits are not significant. .000089 =2 sig. fig.
4. zeros at the end of a number and to the right of a decimal point are always significant. 43.00 & 1.010 = 4 sig. fig.
5. zeros at the rightmost end of a measurement the lie to the left of an understood decimal point are not significant if they serve has placeholders to show the magnitude of the number.
6. Always significant. When….
- when you count a specific number like 23 people in your classroom.
- An exactly defined quantity found w/ in a system of measurements.
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7. Addition and Subtraction - least precise measurement.
12.52 + 349 + 8.24 = 369. 76 m ….. = 369 or 3. 698 x 102
8. Multiplication and Division - least number or significant figures.
7.55m x .34 = 2.567….= 2.6m
SI base units
Length -meter (m)
Mass - kilogram (kg)
Temperature - kelvin (k)
Time - second (s)
Amount of substance - mole (mol)
Luminous Intensity - candela (cd)
Electric Current - ampere (A)
Volume - liter (L)
SI base units
Length -meter (m)
Mass - kilogram (kg)
Temperature - kelvin (k)
Time - second (s)
Amount of substance - mole (mol)
Luminous Intensity - candela (cd)
Electric Current - ampere (A)
Volume - liter (L)
Prefixes
Mega (M) - 10 to the 6th, 1 million times larger
Kilo (K) - 10 to the 3rd, 100 times larger
Deci (d )- 10 to the -1st, 10 times smaller
Centi (c) - 10 to the -2nd. 100 times smaller
Milli (m) - 10 to the -3rd, 100o times smaller
Micro (u) - 10 to the -6th, 1 million times smaller
Nano (n) - 10 to the -9th, 1000 million times smaller
- Conversion Factors: a ratio of equivalent measurements. The numerical value is changed, but the actual size of the quantity measured stays the same.
- Scientific Notation: a given number is written as a product of two numbers. Ex. 602, 000, 000 = 2.02 x 10 8
- Density = mass/volume
- intensive prop.
-The density of a substance decreases as its temp. increases.