Atomic Structure
What are valance electrons?
Valance electrons are the negative charge on the outer part of the shell.
What are isotopes?
Atoms of the same element that have different numbers of neutrons.
What is Avogardo’s number?
Mass of one mole of a substance = molar mass symbolized by MM. Units include g/mol.
What kind of bond forms when a nonmetal and metal are present?
Ionic bond
What are the two main categories of pure substances?
Elements and Compounds
The principle that states that electrons will first occupy the lowest energy orbitals available before filling higher energy orbitals.
Aufbau Principle
Identify the four elements that stable with only 2 valance electrons
Hydrogen, Helium, Lithium and Beryllium
How many moles are present in 4.0 grams of sodium hydroxide (NaOH, molar mass = 40 g/mol)?
0.1 moles (moles = mass / molar mass = 4.0 g / 40 g/mol = 0.1 mol)
Identify the type of reaction that would form if two or more substances combine to form a single product
(ex: A + B → AB).
Synthesis
Define a homogeneous and heterogeneous mixtures
Homogeneous(same) mixture - a mixture with uniform composition and components cannot be separated easily.
Heterogeneous( different ) mixture- a mixture that is not uniform throughout and components of the mixture can be separated easily
What are the three main particles in an atomic structure?
Protons , Neutrons, and Electrons
Define Spectroscopy
Study of absorption and emission of lights by atoms
Balance and identity the following equation below
H3AsO4 → As2O5+H2O
Type of reaction: Decomposition
Balance : 2H3AsO4 → As2O5+3H2O
What happens in a combustion reaction?
Answer: Reaction with oxygen, often producing heat and light
Explain the difference between a physical and chemical change?
Physical changes modify a substance's look or state without altering its chemical makeup, whereas chemical changes create entirely new substances.
What are regions of space around the nucleus where electrons are likely to be found.
Orbitals
List some rules that must be followed in Aufabau Principle and or the amount of orbitals for each energy level
S orbitals =2 electrons
P orbitals = 6 electrons
D orbitals = 10 electrons
F orbitals = 14 electrons
How many atoms are in 18.46 grams of copper?
1.8 x 10^23 atoms
Balance the following equation
Fe₂O₃ + CO → Fe + CO₂
Answer: Fe₂O₃ + 3CO → 2Fe + 3CO₂
What does the term "viscosity" describe?
How well something can pour. Thick liquids have high viscosity, runny liquids have low viscosity.
What is the mass number?
How do you find the mass number of an element?
The mass number is the total number of protons and neutrons in an atom's nucleus. You can found the mass number by adding the number of protons and neutrons together.
Why must chemical equation be balanced?
Chemical equations must be balanced to adhere to the Law of Conservation of Mass. Law of Conservation states that matter cannot be created, conserved nor destroyed to keep it the same number of each type of atom on both sides of the equation
Balance and Identify the equation below
Al(OH)3+HBr → AlBr3 + H2O
Type of reaction : Double Replacement/Displacement
Answer: Al(OH)3+3HBr → AlBr3 + 3H2O
What is the difference between ionic and covalent bond formation.
Ionic bonds involve the transfer of electrons, resulting in electrostatic attraction between oppositely charged ions, while covalent bonds involve the sharing of electrons between atoms.
How can density be calculated?
Density is calculated by dividing the mass of a substance by its volume (Density = Mass / Volume).