Chemistry Quiz: Reactions and Electron Configurations

A chemical equation is balanced when the number of atoms of each element on the reactant side equals the number of atoms of that element on the product side. This ensures that the law of conservation of mass is upheld during a chemical reaction.

To balance an equation, you adjust the stoichiometric coefficients, which are the numbers before each chemical formula, until the number of atoms of each element is identical on both sides.

The equation is balanced when there are 4 hydrogen atoms, 3 boron atoms, and 6 oxygen atoms on both sides.

The balanced equation is P4 + 16 H2O → 4 PH3 + 4 H3PO4. This equation has 4 phosphorus atoms, 32 hydrogen atoms, and 16 oxygen atoms on each side.

The coefficients in a balanced equation represent the number of moles of each reactant and product involved in the reaction.

In a chemical reaction, the total number of atoms of each element remains the same on both sides of the equation. This means that atoms are neither created nor destroyed, but rearranged.

The reactant that is completely consumed first in a chemical reaction, limiting the amount of product that can be formed.

A chemical reaction where electrons are transferred between reactants. It involves changes in oxidation numbers.

Reactions that don't involve the transfer of electrons, they usually involve the formation or breaking of bonds between atoms.

The sum of the atomic masses of all atoms present in a molecule. It represents the mass of one molecule of the compound.

An acid that donates a proton (H+).

A base that accepts a proton (H+).

The strength of a base is inversely proportional to the strength of its conjugate acid. A stronger acid has a weaker conjugate base.

A substance formed when a base gains a proton.

A substance formed when an acid loses a proton.

The atomic number of an element represents the number of protons present in the nucleus of its atom.

In a neutral atom, the number of negatively charged electrons always equals the number of positively charged protons.

The principal quantum number (n) determines the energy level of an electron, while the angular momentum quantum number (l) specifies the shape of the electron's orbital. For n = 2, the possible values of l are 0 and 1, corresponding to an s orbital (l = 0) and a p orbital (l = 1).

The magnetic quantum number (ml) describes the orientation of an electron orbital in space. For l = 1 (p orbital), the possible values of ml are -1, 0, and +1, indicating three different spatial orientations of the p orbital.

The p subshell is characterized by its shape, which is dumbbell-like. It is characterized by 'l' being equal to 1.

A p subshell consists of three orbitals, each with a different spatial orientation, characterized by the ml values of -1, 0, and +1.

An f subshell comprises seven orbitals, each with a unique spatial orientation, as indicated by ml values of -3, -2, -1, 0, +1, +2, and +3. Each orbital has a distinct and complex shape.

The atomic mass of an element is the weighted average of the atomic masses of its naturally occurring isotopes. The percent natural abundance of each isotope is used as the weighting factor in this calculation.

The pH scale is logarithmic, meaning each unit change represents a tenfold difference in hydrogen ion concentration. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic. [H+]=1 x 10^-7 = neutral.

The product of the hydrogen ion concentration [H+] and the hydroxide ion concentration [OH-] in water is always equal to a constant value, Kw, which is 1.0 x 10⁻¹⁴ at 25°C. This relationship helps us understand the balance between acidity and basicity in aqueous solutions.

The pOH of a solution is the negative logarithm of the hydroxide ion concentration. [OH⁻]

The acid ionization constant (Ka) is a measure of the strength of an acid. A larger Ka value indicates a stronger acid that ionizes more in solution. Ka = [H+][A-] / [HA].

A Lewis base is a species that donates a pair of electrons, forming a covalent bond with an electron-deficient species (Lewis acid).

The number of atoms in one mole of any substance is constant, known as Avogadro's number ($6.02 \times 10^{23}$). This means 1 mole of any substance contains the same number of particles.

The mass of one mole of a substance is called its molar mass. It is expressed in grams per mole (g/mol) and can be determined by adding the atomic masses of all atoms in the chemical formula.

The limiting reactant is the reactant that gets completely consumed first in a reaction, determining the amount of product that can be formed.

The percentage yield is the actual amount of product obtained in a reaction compared to the theoretical maximum amount expected, expressed as a percentage. It reflects the efficiency of the reaction.

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

The wavelength of light emitted during an electron transition from a higher energy level (n=3) to a lower energy level (n=1) in a hydrogen atom.

The set of three quantum numbers (n, l, ml) uniquely identifies an atomic orbital. n represents the principal quantum number, determining the energy level. l refers to the angular momentum quantum number, characterizing the shape of the orbital. ml, the magnetic quantum number, describes the spatial orientation of the orbital.

The ground-state electron configuration of an element describes the arrangement of electrons in its lowest energy state. It follows specific rules like the Aufbau principle, Hund's rule, and the Pauli exclusion principle.

Elements in the periodic table are categorized into periods and groups. Periods represent horizontal rows, signifying the same principal quantum number (n). Groups, the vertical columns, designate elements with similar chemical properties due to the same number of valence electrons.

The orbital designation depends on the values of n and l. n dictates the energy level, and l describes the shape of the orbital (s, p, d, or f). For example, n=3, l=1 corresponds to a 3p orbital.

The positive charge of an atom's nucleus, equal to the number of protons.

The number of electrons an atom gains or loses to achieve a stable, noble gas configuration.

Energy required to remove one electron from a gaseous atom in its ground state.

Ability of an atom to attract electrons in a covalent bond.

The region around the nucleus where an electron is most likely to be found.

A set of four quantum numbers that describe the state of an electron in an atom.

A region of space around the nucleus where there is a high probability of finding an electron.

The arrangement of electrons in different energy levels and sublevels within an atom.