WorksheetsPHY351 CHAPTER 1 weak secondary bonds
Total questions: 19
Worksheet time: 10mins
Secondary (weak) bonds are best described as:
Forces of attraction between molecules that are weaker than primary bonds
Strong covalent bonds between atoms
Ionic bonds that form crystal lattices
Metallic bonds responsible for conductivity
Secondary bonds are different from primary (strong) bonds such as ionic or covalent bonds because:
they are generally weaker than primary bonds.
they involve the transfer of electrons between atoms.
they form the main structure of molecules.
they are always stronger than covalent bonds.
Van der Waals forces are defined as:
Weak intermolecular forces of attraction between molecules.
Strong covalent bonds between atoms.
Electrostatic forces between ions and electrons.
Forces responsible for nuclear fusion.
A temporary (fluctuating) dipole in an atom or molecule is caused by:
the random movement of electrons within the atom or molecule
the presence of a permanent dipole
the addition of external energy
the loss of protons from the nucleus
A dipole is defined as:
A pair of equal and opposite charges separated by a small distance.
A single positive charge.
A group of electrons moving in a circle.
A neutral atom with no charge.
6. One example of a molecule where Van der Waals forces exist is:
O2
NaCl
H2SO4
CaCO3
Van der Waals forces are considered weak because:
they arise from temporary dipoles and have low energy
they involve strong covalent bonds
they are responsible for metallic bonding
they result from the sharing of electrons
Hydrogen bonding is defined as:
A type of attractive force between a hydrogen atom and an electronegative atom such as oxygen, nitrogen, or fluorine.
A bond formed by sharing of electrons between two atoms.
A force that holds ions together in an ionic compound.
A type of bond formed only between hydrogen atoms.
The three atoms that commonly form hydrogen bonds with hydrogen are:
Oxygen, Nitrogen, and Fluorine
Carbon, Sulfur, and Phosphorus
Helium, Neon, and Argon
Chlorine, Bromine, and Iodine
One example of a compound that forms hydrogen bonds between its molecules is:
Water (H₂O)
Methane (CH₄)
Carbon dioxide (CO₂)
Sodium chloride (NaCl)
A temporary dipole is different from a permanent dipole in that:
A temporary dipole is induced and lasts for a short time, while a permanent dipole is due to a constant difference in electronegativity between atoms.
A temporary dipole is always present in polar molecules, while a permanent dipole only occurs in nonpolar molecules.
A temporary dipole is caused by ionic bonds, while a permanent dipole is caused by metallic bonds.
A temporary dipole has a fixed direction, while a permanent dipole changes direction constantly.
Hydrogen bonds are stronger than Van der Waals forces because:
they involve stronger electrostatic attractions between molecules.
they are formed only between noble gases.
they are weaker than covalent bonds.
they do not involve any attraction between molecules.
The importance of hydrogen bonding in water (H₂O) is:
It gives water its unique properties such as high boiling point and surface tension.
It makes water a good conductor of electricity.
It causes water to be non-polar.
It prevents water from dissolving salts.
Water (H₂O) has a higher boiling point than methane (CH₄) even though both are small molecules because:
Water forms hydrogen bonds, which require more energy to break.
Methane has a higher molecular mass than water.
Methane forms hydrogen bonds, which require more energy to break.
Water has a lower molecular mass than methane.
Van der Waals forces are most significant in which state of matter?
Solid
Liquid
Gas
Plasma
Fluctuating dipoles lead to attraction between molecules by:
inducing temporary dipoles in neighboring molecules, resulting in London dispersion forces.
forming permanent covalent bonds between molecules.
causing molecules to repel each other strongly.
increasing the kinetic energy of the molecules, leading to separation.
One biological example where hydrogen bonding is important is:
The structure of DNA
The process of photosynthesis
The function of ribosomes
The movement of cilia
The relative strength of Van der Waals, hydrogen bonds, and covalent bonds can be compared as follows:
Covalent bonds are strongest, followed by hydrogen bonds, then Van der Waals forces.
Van der Waals forces are strongest, followed by covalent bonds, then hydrogen bonds.
Hydrogen bonds are strongest, followed by Van der Waals forces, then covalent bonds.
Van der Waals forces are strongest, followed by hydrogen bonds, then covalent bonds.
State one everyday example where hydrogen bonding affects a material’s property.
Water has a high boiling point due to hydrogen bonding.
Iron rusts quickly due to hydrogen bonding.
Plastic melts easily because of hydrogen bonding.
Glass is transparent because of hydrogen bonding.
