MCAT - General Chemistry Questions
and Answers | Latest Version | 2024/2025
| 100% Pass
What is the definition of an isotope?
✔✔An isotope is a variant of an element that has the same number of protons but a different
number of neutrons in its nucleus.
What does the term "electronegativity" refer to?
✔✔Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a
chemical bond.
What is the principle behind the concept of "Le Chatelier's Principle"?
✔✔Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the
conditions, the system will adjust itself to counteract the change and restore equilibrium.
1
,How is the pH of a solution related to the concentration of hydrogen ions?
✔✔The pH of a solution is the negative logarithm of the hydrogen ion concentration; a lower pH
indicates a higher concentration of hydrogen ions.
What is the difference between an ionic bond and a covalent bond?
✔✔An ionic bond is formed through the transfer of electrons from one atom to another, resulting
in oppositely charged ions. A covalent bond is formed by the sharing of electrons between
atoms.
What is the role of a catalyst in a chemical reaction?
✔✔A catalyst speeds up a chemical reaction by lowering the activation energy required, without
being consumed in the process.
What is the law of conservation of mass?
2
,✔✔The law of conservation of mass states that mass cannot be created or destroyed in a
chemical reaction; the total mass of reactants equals the total mass of products.
What is the ideal gas law equation?
✔✔The ideal gas law equation is PV = nRT, where P is pressure, V is volume, n is the number
of moles, R is the gas constant, and T is temperature.
How do you calculate the molar mass of a compound?
✔✔The molar mass of a compound is calculated by summing the atomic masses of all the atoms
present in its molecular formula.
What is the difference between an exothermic and an endothermic reaction?
✔✔An exothermic reaction releases heat to the surroundings, while an endothermic reaction
absorbs heat from the surroundings.
electron affinity
3
, The energy released when an atom or ion in the gaseous state gains an electron. Increases from
left to right and from bottom to top on the Periodic Table.
electrolyte
An ion in water that is capable of conducting electricity in that solution.
electrochemical reaction
A chemical reaction that either is driven by or produced electricity.
double-displacement reaction
A chemical reaction in which two different compounds exchange an atom or ion to form two
new compounds; also called a metathesis reaction.
diffusion
4
and Answers | Latest Version | 2024/2025
| 100% Pass
What is the definition of an isotope?
✔✔An isotope is a variant of an element that has the same number of protons but a different
number of neutrons in its nucleus.
What does the term "electronegativity" refer to?
✔✔Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a
chemical bond.
What is the principle behind the concept of "Le Chatelier's Principle"?
✔✔Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the
conditions, the system will adjust itself to counteract the change and restore equilibrium.
1
,How is the pH of a solution related to the concentration of hydrogen ions?
✔✔The pH of a solution is the negative logarithm of the hydrogen ion concentration; a lower pH
indicates a higher concentration of hydrogen ions.
What is the difference between an ionic bond and a covalent bond?
✔✔An ionic bond is formed through the transfer of electrons from one atom to another, resulting
in oppositely charged ions. A covalent bond is formed by the sharing of electrons between
atoms.
What is the role of a catalyst in a chemical reaction?
✔✔A catalyst speeds up a chemical reaction by lowering the activation energy required, without
being consumed in the process.
What is the law of conservation of mass?
2
,✔✔The law of conservation of mass states that mass cannot be created or destroyed in a
chemical reaction; the total mass of reactants equals the total mass of products.
What is the ideal gas law equation?
✔✔The ideal gas law equation is PV = nRT, where P is pressure, V is volume, n is the number
of moles, R is the gas constant, and T is temperature.
How do you calculate the molar mass of a compound?
✔✔The molar mass of a compound is calculated by summing the atomic masses of all the atoms
present in its molecular formula.
What is the difference between an exothermic and an endothermic reaction?
✔✔An exothermic reaction releases heat to the surroundings, while an endothermic reaction
absorbs heat from the surroundings.
electron affinity
3
, The energy released when an atom or ion in the gaseous state gains an electron. Increases from
left to right and from bottom to top on the Periodic Table.
electrolyte
An ion in water that is capable of conducting electricity in that solution.
electrochemical reaction
A chemical reaction that either is driven by or produced electricity.
double-displacement reaction
A chemical reaction in which two different compounds exchange an atom or ion to form two
new compounds; also called a metathesis reaction.
diffusion
4
