Chem Test 1 Flashcards
What are the main branches of chemistry?
- Organic
- Inorganic
- Analytical
- Physical
- Biochemistry
Which branch of chemistry deals with CARBON compounds?
Organic
What is the difference between a homogeneous and a heterogeneous mixture?
Homogeneous mixtures are uniform throughout (e.g., salt water), while heterogeneous mixtures are not uniform (e.g., salad).
How do you classify matter?
Matter can be classified as
- elements
- compounds
- mixtures.
What is the difference between a compound and a homogeneous mixture?
- compound is a pure substance that can only be separated by chemical means,
- homogeneous mixture can be separated by physical means.
What are physical properties?
Physical properties can be observed or measured WITHOUT CHANGING the substance (e.g., density, solubility).
What are chemical properties?
Chemical properties describe a substance’s ability to undergo chemical changes (e.g., flammability).
Name some common lab equipment used for measuring volumes.
Beakers, graduated cylinders
What are some methods used to separate mixtures?
Filtration, distillation, and chromatography.
What is an SDS used for?
An SDS provides safety information about chemicals, including hazards and safe handling instructions.
What safety precautions should be taken when handling chemicals?
Wear goggles, use fume hoods for volatile chemicals, and handle acids with care.
What is the difference between an independent and a dependent variable?
An independent variable is manipulated and placed on the x-axis, while the dependent variable is observed and placed on the y-axis.
What is a direct relationship?
In a direct relationship, as one variable INCREASES, the other also INCREASES.
What is an inverse relationship?
In an inverse relationship, as one variable INCREASES, the other DECREASES.
What is the law of conservation of mass?
In any physical or chemical change, mass is neither created nor destroyed.
What is the difference between a scientific theory and a scientific law?
- theory explains why something happens
- law describes what happens.
What are reactants and products in a chemical reaction?
- Reactants are substances that undergo change
- products are the new substances formed.
What are some aspects of the nature of science?
Science is based on evidence, is subject to change, and involves peer review.
Which branch of chemistry deals with NON-CARBON compounds?
Inorganic
Which branch of chemistry deals with COMPOSITION of samples?
Analytical
Which branch of chemistry deals with the BEHAVIOR/ENERGY of compounds?
Physical
Which branch of chemistry deals with the chemistry of LIFE?
Biochemical
The natural world is _____
Understandable
Science is based on _____
evidence
Scientific ideas are _____ yet subject to _____
- durable
- change
Science is a complex _____ _____
Social endeavor
Scientists try to remain _____ and _____ in peer review to avoid _____
- objective
- engage
- bias
A scientific law is a short _____ statement of ____ happens
- mathematical
- WHAT
A Summary
A scientific law _____ try to explain the relationship it describes
DOES NOT
A scientific law is a _____ _____ for _____ something happens
- Long explanation
- WHY
A theory may need to be _____ at some point in the future to explain new _____ or _____ results
- changed
- observations
- experimental
Theories never become _____
LAWS
We should have only _____ manipulated variable and _____ dependent variable
- one
- one
What does DRY mean for a graph
Dependent variable
Relies on the other
Y-axis
What does MIX mean for a graph
Manipulated Variable
Independent
X-axis
In a direct relationship, y _____ by x equal a _____
So as x is increased, y must _____
- divided
- constant
- increase
in an indirect relationship, x _____ y equals a _____
so as x is increased, y must _____
- times
- constant
- decrease
As the temp of a gas increases, the volume increase. This is a _____ relationshipo
direct
As the volume of a gas decreases, the pressure increases, this is a _____ relationship
indirect
What kind of relationship is this graph
Direct
What kind of relationship is this graph
Indirect
Every experiment should have a _____
Control