Wednesday, December 31, 2014

Physical and Chemical Properties

Examples of physical properties are: color, smell, freezing point, boiling point, melting point, infra-red spectrum, attraction (paramagnetic) or repulsion (diamagnetic) to magnets, opacity, viscosity and density. There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance.
Examples of chemical properties are: heat of combustion, reactivity with water, PH, and electromotive force.
The more properties we can identify for a substance, the better we know the nature of that substance. These properties can then help us model the substance and thus understand how this substance will behave under various conditions.

Monday, December 15, 2014

Happy Holidays!


Happy Holidays!







Dear Parents,

Thank you for the support, kinds words, and gifts this past semester. Your thoughtfulness and generosity is deeply appreciated.


Mr. Shadow

Tuesday, December 2, 2014

Matter and 2nd Quarter Exam Study Guide

matter :Anything that has mass and takes up space.


physical properties:Anything you can observe about an object by using your senses. Matter is classified by properties: state of matter, appearance, color, shape, size, texture, magnetic/nonmagnetic, conductor/insulator, odor, solubility...


solid:A form of matter that takes up a specific amount of space and has a definite shape. Its molecules are tightly packed together.


liquid:A form of matter that has a definite volume but no definite shape. Molecules are more loosely packed and move more freely.


gas:A form of matter that does not have a definite shape or a definite volume. Molecules move most freely.

 

melting process:Occurs when heat energy is applied and energy increases. When heat is applied, a solid turns to a liquid.


evaporation process:Occurs when more heat is applied; again energy increases and therefore, molecules move more rapidly. When heat is applied, a liquid turns to a gas.


condensation process:Occurs when molecules are cooled, condense and energy is lost. When cooled, a gas turns to a liquid. Clouds, dew, water droplets on the outside of a glass on a hot day are caused by condensation.


freezing process:Occurs when molecules are cooled even more, and more energy is lost. When cooled even more, a liquid turns to a solid.


plasma:A form of matter that, like gas, has no definite shape nor definite volume. Common forms of plasma include stars and neon signs.


mass:The measure of how much matter is contained in an object.


weight:The measure of the force (pull) of gravity between the Earth and an object.


density:A measure of how tightly packed matter is. The more matter that gets packed into the same amount of space, the more dense it is.


volume:The amount of space matter takes up.


boiling point:Refers to the temperature at which it boils; every substance has its own constant boiling point. Waters boiling point is 100C/212F.


melting point:Refers to the temperature at which it melts; every substance has its own constant melting point. Waters (ice) melting point is 0C/32F.


freezing point:Refers to the temperature at which it freezes; every substance has its own constant boiling point. Waters freezing point is 0C/32F.


grams or kilograms

Mass is measured in these metric units.

celsius

Metric unit for measuring temperature; on this scale water freezes at zero and boils at 100. A Swedish astronomer devised the centigrade thermometer, (1701-1744).

fahrenheit

A scale and unit of measurement for temperature. It has been replaced in most countries by the Celsius scale. A German physicist invented the mercury thermometer and developed the scale of temperature that bears his name, (1686-1736).

scale

A tool used to measure weight.

graduated cylinder

A tool used to measure volume and density.

temperature

The measure of the amount of heat energy in the atmosphere.

physical state

The forms matter can be found in; examples are solid, liquid, and gas.

substance

Matter that has a uniform and unchanging composition.

balance scale

The balance scale is a tool used to measure the amount of mass in an object.