mellows quiz 3

Accuracy

How close a measurement is to the known, accepted, or correct value

Precision (A)

How close several measurements are to each other

Precision (B)

How well you know a number, how many sig figs it has

Matter

Anything with value and mass

Pure substance

A form of matter that consists of only one element or compound with a uniform composition.

examples: gold, or water- cannot be separated into different components by physical means

Elements

A substance made from just one type of atom

any element on the periodic table

Compounds

A pure chemical substance made of two or more different elements chemically bonded together in a fixed proportion

Mixture

A physical combination of two or more substances that are not chemically bonded and retain their individual chemical properties

Cheerios and peanuts are an example of a ______

Mixture

Water is an example of a ____

compound

Heterogenous mixture

Different in different parts (particles distributed NON uniformly)

Homogenous mixture

The same all over (particles distributed uniformly)

Ice in soda is an example of a ____

Heterogeneous mixture

Air is an example of a ______

Homogeneous mixture

Equation of thickness

Thickness = mass/(density*area)

Equation of volume

Volume=mass/density

non zero digits (1,2,3,4…)

Always significant

leading zeros (0.001, 0.72)

Never significant

trailing zeroes

Significant IF: after a decimal point,

ex. 0.70 or 0.0560

Not significant IF: not after a decimal,

ex. 200, 30

Extensive Properties

affected by amount of matter such as mass and volume.

Intensive Properties

NOT affected by amount of matter

Water’s boiling point is 100 C even if you have a cup or a gallon

example of an intensive property

An object’s mass will increase if there is more matter

example of an extensive property