DAT General Chemistry Questions and
Answers | Latest Update | 2024/2025 |
Graded A+
How is the periodic table arranged to reflect the properties of elements?
✔✔ The periodic table is arranged by increasing atomic number, with elements grouped into
columns (groups) and rows (periods) that reflect similar chemical properties and trends in atomic
structure.
What is the role of a chemical equation in representing a chemical reaction?
✔✔ A chemical equation represents a chemical reaction by showing the reactants, products, and
their relative amounts, allowing us to understand the stoichiometry and predict the quantities of
substances involved.
How do you determine the empirical formula of a compound from its percent composition?
✔✔ The empirical formula is determined by converting the percent composition to moles,
finding the simplest whole number ratio of the elements, and using this ratio to write the
empirical formula.
What is the significance of the octet rule in chemical bonding?
1
,✔✔ The octet rule states that atoms tend to gain, lose, or share electrons to achieve a stable
electron configuration with eight electrons in their outer shell, which drives the formation of
bonds.
How does the concept of lattice energy explain the stability of ionic compounds?
✔✔ Lattice energy explains the stability of ionic compounds by describing the energy released
when gaseous ions form a solid lattice; higher lattice energy indicates a more stable ionic
compound.
What factors influence the rate of a chemical reaction?
✔✔ Factors influencing the rate of a chemical reaction include the concentration of reactants,
temperature, presence of a catalyst, and the surface area of the reactants.
What is the difference between a solution and a colloid in terms of particle size and behavior?
✔✔ A solution has particles at the molecular or ionic level, which are not visible and do not
settle out, while a colloid has intermediate-sized particles that remain dispersed and can scatter
light, but do not settle out.
How can you identify the type of hybridization an atom undergoes in a molecule?
2
, ✔✔ The type of hybridization can be identified by examining the number of sigma bonds and
lone pairs around the atom; this determines the geometry and type of hybrid orbitals involved.
What is the role of the principle quantum number in describing electron configuration?
✔✔ The principle quantum number indicates the main energy level or shell in which an electron
resides, influencing the size and energy of the orbital.
How is the concept of molecular geometry used to predict the shape of a molecule?
✔✔ Molecular geometry is predicted using the VSEPR (Valence Shell Electron Pair Repulsion)
theory, which considers the arrangement of electron pairs around a central atom to determine the
three-dimensional shape of the molecule.
Atomic Number ✔✔number of protons found in that atom; low number; (Z)
Mass Number ✔✔Protons + Neutrons; high number; (A)
Atomic Mass ✔✔relative mass of that atom compared to the mass of a carbon-12 atom (which is
set at 12.00); measured in amu;
3
Answers | Latest Update | 2024/2025 |
Graded A+
How is the periodic table arranged to reflect the properties of elements?
✔✔ The periodic table is arranged by increasing atomic number, with elements grouped into
columns (groups) and rows (periods) that reflect similar chemical properties and trends in atomic
structure.
What is the role of a chemical equation in representing a chemical reaction?
✔✔ A chemical equation represents a chemical reaction by showing the reactants, products, and
their relative amounts, allowing us to understand the stoichiometry and predict the quantities of
substances involved.
How do you determine the empirical formula of a compound from its percent composition?
✔✔ The empirical formula is determined by converting the percent composition to moles,
finding the simplest whole number ratio of the elements, and using this ratio to write the
empirical formula.
What is the significance of the octet rule in chemical bonding?
1
,✔✔ The octet rule states that atoms tend to gain, lose, or share electrons to achieve a stable
electron configuration with eight electrons in their outer shell, which drives the formation of
bonds.
How does the concept of lattice energy explain the stability of ionic compounds?
✔✔ Lattice energy explains the stability of ionic compounds by describing the energy released
when gaseous ions form a solid lattice; higher lattice energy indicates a more stable ionic
compound.
What factors influence the rate of a chemical reaction?
✔✔ Factors influencing the rate of a chemical reaction include the concentration of reactants,
temperature, presence of a catalyst, and the surface area of the reactants.
What is the difference between a solution and a colloid in terms of particle size and behavior?
✔✔ A solution has particles at the molecular or ionic level, which are not visible and do not
settle out, while a colloid has intermediate-sized particles that remain dispersed and can scatter
light, but do not settle out.
How can you identify the type of hybridization an atom undergoes in a molecule?
2
, ✔✔ The type of hybridization can be identified by examining the number of sigma bonds and
lone pairs around the atom; this determines the geometry and type of hybrid orbitals involved.
What is the role of the principle quantum number in describing electron configuration?
✔✔ The principle quantum number indicates the main energy level or shell in which an electron
resides, influencing the size and energy of the orbital.
How is the concept of molecular geometry used to predict the shape of a molecule?
✔✔ Molecular geometry is predicted using the VSEPR (Valence Shell Electron Pair Repulsion)
theory, which considers the arrangement of electron pairs around a central atom to determine the
three-dimensional shape of the molecule.
Atomic Number ✔✔number of protons found in that atom; low number; (Z)
Mass Number ✔✔Protons + Neutrons; high number; (A)
Atomic Mass ✔✔relative mass of that atom compared to the mass of a carbon-12 atom (which is
set at 12.00); measured in amu;
3
