Chemistry - ✔✔ correct answer - experimental science
- studies the propertiesof materials and the changesthey undergo.
- Supplies answers to questions in almost every aspect of our lives.•
- Ex: Why does ice melt? How do batteries generate electricity? Why do leaves change color?
- a "central science"
Matter - ✔✔ correct answer - a material chemistry studies
- the physical material of the universe
- It is anything that has mass and occupies space.
- has a volume
ex: Our book, your bodies, the clothesyou are wearing, the air we breathe
Mass - ✔✔ correct answer Mass measures the amount of matter in an object
Mass vs. Weight - ✔✔ correct answer - Weight measures the gravitational force between two
objects.
- Weight varies with gravitational force but mass doesn't
Volume - ✔✔ correct answer - the 3-D space that substances contain.
- Volume of a cube: L x W x H
- Volume of a sphere: 4/3 r3
Classification of matter - ✔✔ correct answer - can be classified by its chemical composition
- either a pure substance or a mixture
Elements - ✔✔ correct answer
Pure Substances - ✔✔ correct answer - as the same composition throughout.
- Does not vary from sample to sample.
- It can not be physically separated into all of its components.
- Examples: Water, gold, diamond.
, Intro to Chem: Exam 1 Study Guide
Mixtures - ✔✔ correct answer - a group of two or more elements and/or compoundsthat are
physically intermingled
- It is possible to separate mixtures into their component pure substances.
- Do not have the same composition in every sample
Classification of Pure Substances - ✔✔ correct answer Pure substances can be classified as elements
or compounds
scientific method - ✔✔ correct answer a general approach to problems and involves the following:
1. Making an observation
2. Formulating a hypothesis
3. Testing your hypothesis (experiments)
4. Constructing a theoryto support your observation
Observations - ✔✔ correct answer Natural phenomena and measured events- universally consistent
ones can be stated as a natural law
Ex. Find patterns, trends, and laws
Hypothesis - ✔✔ correct answer Tentative proposal that explains observations
Ex. revised if experiments do not support it
Experiments - ✔✔ correct answer Procedure to test hypothesis- Collect data; measures one variable
at a time
Model/Theory - ✔✔ correct answer set of conceptual assumptions that explains data from
accumulated experiments; predicts related phenomena
ex. altered if predictions do not support it
Element - ✔✔ correct answer - simplest type of substance with unique physical and chemical
properties
- Consists of only one type of atom: smallest unit of an element; building blocks of matter
- Elements cannot be broken down into any simpler substances by physical or chemical means