IB Chemistry 1-2 Semester 2 Final Exam Review

Flashcards covering the comprehensive topics for IB Chemistry 1-2 Semester 2 Final Exam, including Atomic Theory, Stoichiometry, Periodicity, Bonding, and Thermodynamics.

What are the three core components of the scientific method process listed?

Theory, Hypothesis, and Law

In experimental design, what are the three main components of a study?

Research question and hypothesis, Independent and dependent variables, and Controls

How do accuracy and precision differ in chemical measurement?

Accuracy refers to how close a measurement is to the true value, while precision refers to the reproducibility or consistency of measurements.

What are the three temperature scales used in chemistry?

Celsius, Fahrenheit, and Kelvin

How is density defined as a property of matter?

Density is the ratio of mass to volume, often calculated as $\text{Density} = \frac{\text{mass}}{\text{volume}}$.

List the four specific separation techniques for mixtures mentioned.

Filtration, distillation, evaporation, and chromatography

What is the relative charge and location of a proton?

A proton has a relative charge of $+1$ and is located in the nucleus of the atom.

What is the relative charge and mass of an electron?

An electron has a relative charge of $-1$ and a negligible relative mass (approximately $0$) compared to protons and neutrons.

What is the standard used to define relative atomic mass?

Relative atomic mass is a ratio based on the Carbon-12 ($^{12}C$) isotope.

What defines isotopes of an element?

Isotopes are atoms of the same element with different atomic masses due to variable numbers of neutrons.

What is the specific value of Avogadro's Number defined in the notes?

1 mole = $6.022 \times 10^{23}$ particles

What is the molar volume of a gas at STP?

$$22.7\,dm^3$$

What is the difference between an empirical formula and a molecular formula?

The empirical formula is the simplest whole-number ratio of atoms in a compound, while the molecular formula shows the actual number of atoms of each element in a molecule.

What are the five types of chemical reactions identified in Unit 4?

Synthesis, decomposition, single replacement, double replacement, and combustion

What provides evidence for the existence of atomic energy levels in the Bohr Model?

Atomic emission spectra

According to the Aufbau principle, how are electron configurations written?

Electrons fill the lowest energy sub-levels and orbitals first before moving to higher levels.

What does Hund's rule state regarding orbital filling?

Electrons will occupy empty orbitals of the same energy level (sub-level) singly before they begin to pair up.

How is the modern periodic table organized differently than earlier versions?

The current periodic table is based on atomic number rather than atomic mass.

What are the specific chemical families mentioned in the periodic table organization?

Halogens, Noble gases, alkali metals, alkaline earth metals, transition metals, Semimetals, Lanthanide series, and actinide series

What is the trend for atomic radii across a period and down a group?

Atomic radii generally decrease across a period from left to right and increase down a group.

How is electronegativity defined in the context of periodic trends?

Electronegativity is the ability of an atom to attract shared electrons in a chemical bond.

What is the shielding effect and how does it relate to ionization energy?

The shielding effect occurs when inner electrons block the nuclear attraction for outer electrons, which corresponds to the periodic nature of ionization energies.

What characterizes ionic bonding?

Ionic bonding is the electrostatic attraction between cations and anions, forming a repeating lattice rather than true molecules.

What electronegativity difference rule is used to determine if a bond is ionic?

The rule of $1.7$, where a difference greater than this value indicates an ionic bond.

How is covalent bonding defined?

Covalent bonding involves shared electrons between atoms, resulting in the formation of true molecules.

What causes a molecule to be polar covalent?

Unequal sharing of electrons resulting from differences in electronegativity between the bonded atoms.

What describes metallic bonding?

Metal ions existing in a sea of mobile valence electrons.

In Lewis Dot structures, what are resonance structures?

Resonance structures are multiple valid electron dot representations for a single molecule where the actual structure is an average of the forms.

What is the purpose of VSEPR theory?

To describe the shape and bond angles of simple covalent molecules based on electron pair repulsion.

List three examples of giant molecular structures mentioned in the notes.

Diamond, graphite, and silica

What is the formula for the Ideal Gas Law?

$$PV = nRT$$

What are the four primary gas property relationships (laws) explored?

$P$ vs $V$ (Boyle’s Law), $P$ vs $T$ (Gay-Lussac’s Law), $T$ vs $V$ (Charles’s Law), and $n$ vs $V$ (Avogadro’s Law)

What is lattice enthalpy in the context of thermodynamics?

A measure of the strength of the forces between ions in an ionic lattice.

What does a reaction coordinate diagram illustrate?

The energy changes that occur during a chemical reaction from reactants to products.

What are the two series of elements located at the bottom of the periodic table?

Lanthanide series and actinide series

In stoichiometry, how is mass-to-volume of a solution calculated?

By using the molarity ($M$) of the solution.

Which elements are included in the trend for alkali metals?

$$Li \rightarrow Cs$$

What are the four types of orbitals and their relative energies?

$s, p, d,$ and $f$ orbitals, with energy generally increasing in that order within a principal energy level.

What shapes are associated with s and p orbitals?

$s$ orbitals are spherical; $p$ orbitals are dumbbell-shaped.

What specific chemical property of Halogens is mentioned?

The reaction of Halogens ($Cl_2, Br_2,$ and $I_2$) with halide ions ($Cl^-, Br^-,$ and $I^-$).