Mass Is the Amount of Matter a Body Possesses
Chapter 1 & 2
Mass is the amount of matter a body possesses
Weight is the measure of the earths attraction for an object
Objects always have the same mass. . . depending on what planet or where you are, objects have different weights.
Density is defined as mass per unit volume of a material
D = m/v
Ex:If a certain rock has a volume of 3 cm3 and
a mass of 6 g. What is its density?
The Three states of Matter are solid, liquid, and gas.
A Solid has a definite volume & a definite shape [table top]
A Liquid has a definite volume but no definite shape [water]
A Gas has no definite shape and no definite volume [air we breath]
Physical properties are those which can be determined directly without altering the identity or composition of a material
Ex: Boiling point, freezing point, density. . .
Chemical properties describe the behavior of a material in a process that alter the identity of the material
Ex: Flammability, reaction with other materials. . .
Law of Conservation of Matter and Energy-
Matter and energy are interchangeable and the total matter and energy in the universe is constant.
Metric System
Length------meter (m)(in stead of ft and miles)
Mass------grams (g)(not like pounds[a weight])
Volume------liters (L)(in stead of inch3 & gallons)
Prefixes
milli centideciunit deka hectokilo
10-3 10-2 10-1 101 102 103
<------/
/ -- kilo (k)
/
/ -- hecto (h)
/
/ -- deka (da)
/
/ -- unit (gram, meter, liter)
/
/ -- deci (d)
/
/ -- centi (c)
/
/ -- milli (m)
/------>
Ex: 12 kg = _____ g6 cm = _____ m
Ex: 4 cm2 = _____ m2
4 cm cm = _____ m m
= _____ m2
Why is the metric system better than the English system?
Ans. How many ft. are in 6 miles? . . .
[take a look at table 1-3 on pg 15; Talk about English to Metric comparisons and conversions]
Heat is the energy transfer between two systems due to the temperature difference
Ex: Ice melting; coke getting cold due to ice cubes
Temperature is a measure of a systems ability to transfer heat
A calorie is the heat required to raise the temperature of 1 gram of water through
1 Celsius degree
A kilocalorie is the heat required to raise the temperature of 1 kilogram of water through
1 Celsius degree
(this is the what the industry calls a calorie)
Significant digits are all the known digits plus the first uncertain digit
Exponential notation or scientific notation has the formM x 10n
Where M is a number between 1 and 10 (one digit left of the decimal point) and
n is an integer.
Ex: 1500 = 1.5 * 1000 = 1.5 * 103
Ex: 0.0015 = 1.5 * 0.001 = 1.5 * 10-3
(may need to show student how to put in calculator)
Heterogeneous matter has different properties through out it
Ex: Granite rock (has different materials through out)
Homogeneous matter has identical properties through out it
Ex: Water, coffee. . .
A mixture consists of two or more kinds of matter each retaining its own characteristic properties
Ex: Salt water, coffee. . .
A compound is a substance that can be decomposed into two or more simpler substances by ordinary chemical means
Ex: the compound water, which is composed of H and O
Elements are substances that cannot be further decomposed by ordinary chemical means
Ex: H, O, gold silver
Law of definite composition - each compound has a definite composition by mass
Ex: No matter where we find pure water the same amount of any other pure water will weight the same (also density) (Archimedes and the gold crown)
Physical changes are changes which involve physical properties but the identity of the matter is not changed
Ex: boiling, freezing, solubility (but you can always get the original substance back)
During chemical changes different substances with new properties are formed
Ex: burning; reacted. . . (it is not possible the get the original substance back)
Endothermic reactions absorb energy
Ex: Calcium carbide formation; see page 53 in book for info
Exothermic reactions release energy
Ex: Sodium added to water (a violent explosion and heat generated)
A precipitate is an insoluble solid formed when two or more solutions are mixed
Ex: Silver Nitrate and Hydrochloric acid
A catalyst is a substance that changes the rate of a chemical reaction without interfering with the reaction itself
During a nuclear change a new substance is formed by changes in the identity of the atoms
Ex: Silver turning to lead (tarnish)