Openstax section 1.1-1.6

Accuracy

How close something is to a right or true answer

Atom

The smallest unit of an element that still has element properties

Chemical change

When something new is made

Chemical property

How something reacts or changes into something new

Compound

A substance made when two or more elements are CHEMICALLY joined

Element

A pure substance made of only one type of atom

Exact number

A number thats completely certain: like 4 people

Extensive property

Depends on how much matter there is (mass or volume)

Gas

Has no definite shape or volume; it spreads out and fills its container

Heterogeneous Mixture

You can see the different parts like a salad

Homogeneus Mixture

Looks the same all the way through (like salt water)

Hypothesis

A testable guess or idea about how something works

Intensive Property

Doesnt change no matter how much you have (like density or color)

Law

A rule that describes something that always happen in nature

Law of conservation of mass

Matter  isnt crated or destroyed it just changes forms

Liquid

Has a set volume but takes the shape of its container

Macroscopic domain

The stuff we can see with our eyes

Mass

How much matter is in something

Microscopic domain

The tiny world of atomas and molecules that we cant see directy

Mixture

When two or more substances are blended together but not chemically combiend like trail mix

Molecule

two or morew atoms bonded together.

Observation

Using your senses to notice or describe something

Physical Change

When something changes how it looks but stays th same substance for example melting or cutting

Physical Property

Something you can see or measure without changing what it is like size

Plasma

A supar hot gas made of charged particles

Pure substance

Has only one kind of material like water or gold

Precision

When you get almost the same result everytime you measure

Qualitative observation

Describing something without using numbers/ measurements

Round to Even- Rules of 5’s

If a number ends in 5 round it to the nearest even number

Scientific method

The steps scientists use to study and test ideas

SI units (international system of units)

The system scientists use to measure things

Significant Figures

The important digits in a measurement that show how exact it is

Symbolic domain

The symbols formulas and equations used to represent what’s happening in chemistry

Theory

A big idea that explains why something happens and is supported by lots of evidence

Uncertainty

How unsure or off a measurement might be

Unit Conversion Factor

A number used to change one unit to another

Units 

The labels we use to show what we’re measuring

Volume

How much space something takes up

Weight

How heavy something is because of gravity