Chemistry 130 Arizona College of
Nursing Midterm Questions with Verified
Solutions
What is the atomic number of an element, and why is it important?
✔✔The atomic number is the number of protons in an atom’s nucleus and determines the
element's identity and position on the periodic table.
How does an ionic bond form between atoms?
✔✔An ionic bond forms when one atom donates an electron to another atom, creating oppositely
charged ions that attract each other.
What is the difference between a covalent bond and an ionic bond?
✔✔A covalent bond involves the sharing of electrons between atoms, while an ionic bond
involves the transfer of electrons from one atom to another.
Why is water considered a polar molecule?
✔✔Water is polar because it has an uneven distribution of electrons, with oxygen being slightly
negative and hydrogen slightly positive, creating a dipole.
1
,What is the law of conservation of mass?
✔✔The law of conservation of mass states that mass cannot be created or destroyed in a
chemical reaction; the mass of reactants equals the mass of the products.
How does temperature affect the rate of a chemical reaction?
✔✔Increasing the temperature typically increases the rate of a chemical reaction by providing
more energy for particles to collide and react.
What is the purpose of a catalyst in a chemical reaction?
✔✔A catalyst speeds up a chemical reaction by lowering the activation energy without being
consumed in the process.
How do acids and bases differ in terms of hydrogen ions?
✔✔Acids donate hydrogen ions (H⁺) in a solution, while bases accept hydrogen ions or produce
hydroxide ions (OH⁻).
What happens when you mix an acid with a base?
✔✔When an acid and a base are mixed, they undergo a neutralization reaction, typically
producing water and a salt.
2
, What is the pH scale, and what does it measure?
✔✔The pH scale measures the concentration of hydrogen ions in a solution, indicating its acidity
or alkalinity, with a range from 0 (acidic) to 14 (basic).
Why is carbon so versatile in forming compounds?
✔✔Carbon is versatile because it can form four covalent bonds, allowing it to create a wide
variety of complex molecules, including chains and rings.
What is Avogadro's number, and why is it important?
✔✔Avogadro's number is 6.022 x 10²³, representing the number of particles (atoms, molecules)
in one mole of a substance, essential for converting between atomic and macroscopic scales.
How do valence electrons determine chemical reactivity?
✔✔Valence electrons are the outermost electrons of an atom and determine how it interacts with
other atoms, particularly in forming bonds.
What is the difference between an endothermic and exothermic reaction?
3
Nursing Midterm Questions with Verified
Solutions
What is the atomic number of an element, and why is it important?
✔✔The atomic number is the number of protons in an atom’s nucleus and determines the
element's identity and position on the periodic table.
How does an ionic bond form between atoms?
✔✔An ionic bond forms when one atom donates an electron to another atom, creating oppositely
charged ions that attract each other.
What is the difference between a covalent bond and an ionic bond?
✔✔A covalent bond involves the sharing of electrons between atoms, while an ionic bond
involves the transfer of electrons from one atom to another.
Why is water considered a polar molecule?
✔✔Water is polar because it has an uneven distribution of electrons, with oxygen being slightly
negative and hydrogen slightly positive, creating a dipole.
1
,What is the law of conservation of mass?
✔✔The law of conservation of mass states that mass cannot be created or destroyed in a
chemical reaction; the mass of reactants equals the mass of the products.
How does temperature affect the rate of a chemical reaction?
✔✔Increasing the temperature typically increases the rate of a chemical reaction by providing
more energy for particles to collide and react.
What is the purpose of a catalyst in a chemical reaction?
✔✔A catalyst speeds up a chemical reaction by lowering the activation energy without being
consumed in the process.
How do acids and bases differ in terms of hydrogen ions?
✔✔Acids donate hydrogen ions (H⁺) in a solution, while bases accept hydrogen ions or produce
hydroxide ions (OH⁻).
What happens when you mix an acid with a base?
✔✔When an acid and a base are mixed, they undergo a neutralization reaction, typically
producing water and a salt.
2
, What is the pH scale, and what does it measure?
✔✔The pH scale measures the concentration of hydrogen ions in a solution, indicating its acidity
or alkalinity, with a range from 0 (acidic) to 14 (basic).
Why is carbon so versatile in forming compounds?
✔✔Carbon is versatile because it can form four covalent bonds, allowing it to create a wide
variety of complex molecules, including chains and rings.
What is Avogadro's number, and why is it important?
✔✔Avogadro's number is 6.022 x 10²³, representing the number of particles (atoms, molecules)
in one mole of a substance, essential for converting between atomic and macroscopic scales.
How do valence electrons determine chemical reactivity?
✔✔Valence electrons are the outermost electrons of an atom and determine how it interacts with
other atoms, particularly in forming bonds.
What is the difference between an endothermic and exothermic reaction?
3
