3: The Chemistry of Life Flashcards
Module 1, Lesson 3
Life depends on the ____ of the molecules that make up cells.
Chemical properties
The smallest stable component of cells are…
Atoms
Atoms are made up of smaller, unstable particles called…
(three items)
Protons, neutrons, and electrons
What is the charge of a proton?
Positive
What is the charge of a neutron?
Neutral / no charge
What is the charge of an electron?
Negative
Protons and neutrons are located in an atom’s…
Nucleus
True or false:
Most of the volume of an atom is empty space.
True
An atom’s interactions with other atoms are influenced by its…
Electrons
The ____ represents atoms as a nucleus surrounded by rings representing orbitals.
Bohr model
A substance that can’t be broken down into another substance by chemical means is called an…
Element
The number of protons in an element is its…
Atomic number
The amount of a substance is its…
Mass
The force exerted by gravity on an object is its…
Weight
The sum of the masses of an atom’s protons and neutrons is its…
Atomic mass
Atomic mass is measured in…
Daltons
1 Dalton equals…
The mass of a proton or a neutron
Only ____ elements are regularly found in living systems.
12
Most of an organism’s mass is made up of…
(four items)
Carbon, oxygen, hydrogen, and nitrogen
Carbon-containing molecules are known as…
Organic molecules
Atoms of the same element that have different numbers of neutrons are called…
Isotopes
An electron’s energy level is related to its distance from the…
Nucleus
Energy is required to move an electron ____ the nucleus.
Away from
Moving an electron towards the nucleus ____ energy.
Releases
Electrons occupy discrete energy levels called…
Quanta
Chemical properties repeat every ____ elements.
Eight
Most elements necessary for life have no more than ____ valence electrons.
Eight
An atom’s chemical behavior is determined by…
How many of its valence positions are filled
Elements with all eight valence electrons tend to be…
Unreactive
The octet rule states that…
Atoms tend to want to establish completely full outer energy levels
Atoms with an electrical charge are called…
Ions
An ion that is positively charged (has more protons than electrons) is called a…
Cation