Ch. 02 - Chemistry Flashcards
Chemistry is the study of what?
the composition of matter
What is matter?
matter is anything that takes up space and has mass
What is mass?
a measure of the amount of matter an object contains
What is weight?
a measure of the pull of gravity on a mass
What are the three states of matter?
Solid, Liquid, and Gas
What’s an element?
a substance that cannot be broken down into other substances by chemical means
How many naturally occurring elements are there?
92
How many of the naturally occurring elements are essential for life?
25
What are the 4 elements that make up 96% of living matter?
Carbon (C), Oxygen (O), Hydrogen (H), Nitrogen (N)
A chemical reaction in which the amount of energy released is greater than the activation energy needed to start the reaction is called:
Exergonic Reaction
What do enzymes do?
- Act as biological catalysts
- They are proteins
- They accelerate chemical reactions
- ALWAYS LOWER the activation energy required to start a chemical reaction
What is an anion?
An anion is a negatively charged atom or group of atoms
A type of reaction in which simple molecules are bonded together to make a larger, more complicated molecule is called a(n) ______ reaction.
Anabolic (or Synthesis) Reaction
What is the type of chemical reaction that breaks a molecule into smaller fragments by breaking its chemical bonds?
Decomposition (catabolic) Reaction
A pure chemical substance made up of atoms of two or more types of elements in a fixed proportion is called _____.
A Compound
