Definitions n Science - n Chemistry -

Definitions n Science - systematic investigation of nature n Chemistry -

Definitions n Science - systematic investigation of nature n Chemistry - study of matter and its properties (physical & chemical)

Divisions of Science

What is Matter?

n Matter is anything that has –Mass –Volume

What is Mass? n Mass is a measure of ….

What is Mass? n Mass is a measure of the quantity of amount n Mass is the amount of matter n How does mass differ from weight?

What are the properties of matter? n Physical n Chemical n Define both and provide an example for each.

Definitions n Physical Property - a property of matter that does not change the kind (type) of matter (ex. Color, phase, temperature, volume, mass) n Chemical Property - a property of matter that changes the type of matter (ex. Burning, reaction with other chemicals)

How do we separate matter into its parts?

What is a compound?

n A compound is composed of two or more elements in a definite proportion. n Examples of compounds are: –H 2 O –CO 2

What is an element?

n An element is the basic building block of all matter n Elements consists of atoms which are the smallest part of matter that can exist and retain the properties of that matter

Elements and the Periodic Table n Look at the periodic table. What do you see? n Describe the letters found on the periodic table.

Elements and the Periodic Table n What does that stepped line mean? n Where are the metals? n Where are the non-metals? n Where are the semi-metals? n What is another name for semi-metals? n Where are the alkali metals?

Elements and the Periodic Table n Where are the alkaline earth metals? n Where are the halogens? n Where are the noble gases? Their old name was inert gases? Do you know why? n Where are the transition elements? n Where are the inner transition elements?

Elements and the Periodic Table n Where are the inner transition elements? n Why are some elements only in outline form? n Is there any significance for a symbols color?

Phases of Matter n Solid – has a definite shape and a definite volume n Liquid – has a definite volume but takes on the shape of the container (no definite shape) n Gas – has neither a definite volume or definite shape

Are there any other phases of Matter? n Good question.

Are there any other phases of Matter? n Good question. The answer is yes; there is a 4 th phase of matter which is called……PLASMA

What is PLASMA? n PLASMA is ……. ?

What is PLASMA? n PLASMA is ……. High temperature, ionized (consists of + and – particles) gases.

Definitions-Properties of Matter n Extensive Property - depends only on the quantity of material (ex. Mass, volume, length) n Intensive Property - depends on the type of matter (ex. Density, melting point, solubility)

Definitions n Precision - Reproducibility of the data n Accuracy - Degree to which the data agree with the true value High Precision and High Accuracy

Precision n Precision is defined as the ability to repeat a measurement n 3 measurements of length include: ä cm ä cm ä cm Indicate good precision or repeatability

Accuracy n Accuracy is how close your value is to the “true” or “accepted” value for a measurement n If your density measurement is 2.72 g/mL and the accepted value is 2.70 g/mL then you have good accuracy