Chemistry of Life (Ch. 2) Flashcards
Anything that has mass and occupies space
Matter
- The amount of material (“stuff”) occupying a space
- The same no matter where you are (even on the moon!)
Mass
The amount of space something takes up
Volume
- The gravitational force pulling on something
- Different depending on where you are (e.g. the moon versus earth)
Weight
- Substance that can’t be broken down into anything simpler (by ordinary chemical means)
- A “pure” substance
- A way of classifying matter
Element
96% of the human body is made up of these four elements (in different combinations)
- Carbon
- Hydrogen
- Oxygen
- Nitrogen
- Smallest piece of an element that has the chemical properties of that element
Atom
The three types of subatomic particles that make up atoms
- Protons
- Neutrons
- Electrons
- Subatomic particles with a positive charge
- Found in the nucleus of an atom
Protons
- Subatomic particles with no charge (neutral)
- Found in the nucleus of an atom
Neutrons
- Subatomic particles with a negative charge
- Orbit outside of the nucleus of an atom
Electrons
- The name for the center of an atom
- Where the protons and neutrons hang out
Nucleus
- Name for the paths electrons take around the outside of an atom’s nucleus
Orbits or shells
The word for the big letter (or two letters) that represents an element on the periodic table or elements
Atomic Symbol
(or Chemical Symbol)
- Unique to each element
- Equal to the number of protons in every atom of that element
- Also equal to the number of electrons every atom of that element starts out with
- The lesser of the two numbers in a box on the periodic table of elements
Atomic Number
- Equal to the (average) number of protons and neutrons added together (for each atom of a specific element)
- The greater of the numbers found in a box on the periodic table of elements
Mass Number (or Atomic Mass Number)
Name the rule:
- Maximum of eight electrons per orbit (shell)
- An atom “wants” eight electrons on an orbit to be “happy”
- This rule does not apply to the FIRST (closest to the nucleus) orbit
- (The first orbit for every atom has a maximum of two electrons)
- 2-8-8-8-… until you run out of electrons
The Octet Rule
For two atoms to form a chemical bond, what has to happen?
(a chemical reaction in which…) their outermost electrons are either TRANSFERRED, or SHARED
What determines what type of chemical reactions (or bonds) an atom will take part in?
The number of electrons leftover on an atom’s outermost shell
Two or more atoms, chemically combined
Molecule
A molecule made up of atoms of two or more different elements
Compound
What do the tiny numbers below each letter in a chemical formula stand for?
- For example: C6H12O6
- Called “subscript”
They stand for how many atoms of each element are in that molecule.
- For example, in C6H12O6:
- 6 atoms of Carbon (C)
- 12 atoms of Hydrogen (H)
- 6 atoms of Oxygen (O)
- = one molecule of the compound glucose
Name the bond:
- Formed by the transfer (giving or recieving) of electrons among atoms
- Results in two oppositely charged ions sticking together, like magnets
- Dissociates easily in water
Ionic bond
An atom with a charge (either positive or negative)
Ion
A positively charged ion
Cation
A negatively charged ion
Anion
Name the bond:
- A bond formed by two or more atoms sharing electrons (to complete each others’ outer shells)
- Represented on paper with dashes:
- Each dash represents an electron being shared between atoms, for example:
- H-H
- O=C=O
Covalent bond
What are the two types of covalent bonds?
- Polar covalent bond
- Nonpolar covalent bond
Name the bond:
- A specific type of covalent bond, where electrons are shared equally between atoms
- Since the shared electron(s) spend an equal amount of time with each atom, both atoms remain neutral (not charged)
Nonpolar covalent bond
Name the bond:
- A specific type of covalent bond, where the electron(s) are unequally shared
- Electrons are more strongly drawn to one atom than the other, so they spend more time hanging out on one the side of the molecule
- The side that the electrons like to hang out at becomes slightly negatively charged (because electrons are negative)
- Molecules made up of these types of bonds dissolve easily in water
Polar covalent bond
Chemical Reactions
If an atom has 1-3 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
A) Electron giver*
*Except in the case of hydrogen. Hydrogen only has one electron total, and is a “sharer.”
Chemical Reactions
If an atom has 4 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
B) Electron sharer
Chemical Reactions
If an atom has 5-7 electrons leftover on its outermost shell, it will “want” to:
A) Give away those electrons (Ionic bond)
B) Share electrons (Covalent bond)
C) Recieve electrons from another atom (Ionic bond)
D) Do nothing, its happy the way it is
C) Electron receiver
Name the bond:
- Very weak
- Formed between polar molecules, like molecules of water
- The reason water is so special!
Hydrogen bonds
- Refers to combining smaller pieces to make something bigger
- Literally means, “join together”
Synthesis
- Refers to breaking down something into smaller pieces
Decomposition