Chapter 2 Flashcards
What is matter?
Matter is anything that takes up space and has mass, it consists of chemical elements in pure form and in combinations called compounds
Element vs. Compound
An element is a substance that cannot be broken down to other substances, meanwhile a compound is a substance consisting of two or more elements in a fixed ratio
What are the subatomic particles that atoms are composed of?
Neutrons (neutral), Protons (positive), Electrons (negative)
What forms the atomic nucleus?
Neutrons and Protons, Electrons surround the nucleus in a cloud
What is an elements atomic number?
The number of protons in that element’s nucleus
What is an elements atomic mass?
The number of protons plus the number of neutrons in the nucleus
What is the maximum number of electrons on the 1st shell?
2
What is the maximum number of electrons on the 2nd shell?
8
If an element has 13 electrons, how many are on the outermost shell?
2 + 8 = 10, 13 - 10 = 3
How many electrons in the 3rd shell is considered to be stable?
8 electrons
How many electrons does each orbital hold?
each orbital holds 2 electrons
What is an isiotope?
Isotopes are two atoms of the same element that differ in number of neutrons, therefore differ in atomic mass
What is the definition of energy?
Energy is the capacity to cause change
What is the definition of potential energy?
Potential energy is the energy that matter has because of its location or structure
What is the potential energy of an electron determined by?
It is determined by the electron shell that it is on; 1st shell has lowest potential energy (lost energy) & 3rd shell has the highest potential energy (absorbed energy)
What are valence electrons?
Valence electrons are those in the outermost shell aka valence shell, which mostly determines the chemical behavior of an atom. For example, an element with full valence shells are considered chemically inert
What is a covalent bond vs a chemical bond?
A covalent bond is the sharing of a pair of valence electrons by 2 atoms and they count as part of each atom’s valence shell. In a chemical bond, atoms transfer or strip each other of valence electrons.
What is an atom’s valence?
An atom’s bonding capacity
What is electronegativity?
Electronegativity is an atom’s attraction for the electrons in a covalent bond, so the more electronegative an atom is, the more strongly it pulls shared electrons towards itself
What happens in a nonpolar covalent bond?
The atoms share the electron equally
What happens in a polar covalent bond?
One atom is more electronegative, therefore the atoms don’t share the electron equally (each atom has a partial positive or partial negative charge)
Cation vs Anion
Cation is positively charged, Anion is negatively charged
What is a hydrogen bond?
A hydrogen bond forms when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom, in living cells these electronegative partners are usually Oxygen and Nitrogen
List bonds from strongest to weakest
Ionic, Covalent, Hydrogen, Van der Waal forces
What are Van der Waals interactions?
Van der Waals interactions are attractions between molecules that are close together as a result of these charges, they are the weakest
Reactants and Products in a Chemical Reaction
Reactants are what you start with and products are what you end with
