Question 1

An atom of carbon has ____ electrons to share to form ____ bonds.
A)2/ionic
B)4/covalent
C)2/covalent
D)4/ionic

Accepted Answer

Carbon has four valence electrons, which it can share to form covalent bonds. Therefore, the best choice is B, which states that an atom of carbon has 4 electrons to share to form covalent bonds. The other choices are incorrect, as carbon typically does not form ionic bonds and does not have only two electrons available for bonding.

Question 2

An anion has:
A)a positive charge
B)a negative charge
C)a neutral charge
D)none of these,because the charge may vary

Accepted Answer

An anion is an ion with a negative charge.

Question 3

The term dissociation refers to:
A)ionic bonds
B)the breaking of bonds in a water solution
C)both A and B
D)both A and B and covalent bonds

Accepted Answer

Dissociation refers to both ionic bonds and the breaking of bonds in a water solution, but not covalent bonds.

Question 4

A covalent bond is formed when:
A)two or more atoms share electrons
B)two atoms form ions and are attracted to each other
C)one atom loses two electrons that are gained by another atom
D)a carbon atom loses all of its electrons to other atoms

Accepted Answer

A covalent bond is a type of chemical bond in which two or more electrons are shared between two atoms. This sharing of electrons allows both atoms to achieve a more stable electron configuration. The atoms do not lose or gain electrons, but rather share them.

Question 5

The bonds that make water cohesive are:
A)disulfide bonds
B)hydrogen bonds
C)ionic bonds
D)water bonds

Accepted Answer

The bonds that make water cohesive are hydrogen bonds. These occur between the oxygen atom of one water molecule and the hydrogen atom of another water molecule. This creates a strong attraction between the molecules and results in the cohesive properties of water.

Question 6

Ionization of salts such as sodium chloride takes place:
A)when the temperature rises
B)when the temperature falls
C)in the solid state
D)in water

Accepted Answer

Ionization of salts such as sodium chloride takes place in water, as water molecules surrounding the salt crystal dissociate the salt into its constituent cations and anions.

Question 7

A synonym for dissociation is:
A)decomposition
B)ionization
C)synthesis
D)reformulation

Accepted Answer

Dissociation and ionization both refer to the separation of molecules or compounds into ions. A is incorrect because decomposition refers to the breakdown of a compound into simpler substances. C is incorrect because synthesis refers to the combination of simpler substances to form a more complex substance. D is incorrect because reformulation refers to the process of changing a substance's composition or form.

Question 8

The bonds that help maintain the three-dimensional shape of proteins and nucleic acids are:
A)covalent bonds
B)hydrogen bonds
C)ionic bonds
D)water bonds

Accepted Answer

Hydrogen bonds are the type of bonds responsible for maintaining the three-dimensional shape of proteins and nucleic acids. Covalent bonds are strong bonds that create the backbone of the molecule, but they do not contribute significantly to the shape. Ionic bonds involve the attraction of opposite charges and can play a role in the structure of certain proteins, but they are not as important as hydrogen bonds. Water bonds are not a recognized type of chemical bond.

Question 9

An anion has:
A)a positive charge,and an example is a hydrogen ion
B)a negative charge,and an example is a bicarbonate ion
C)a positive charge,and an example is a chloride ion
D)a negative charge,and an example is a sodium ion

Accepted Answer

An anion is a negatively charged ion, meaning it has gained electrons. An example of an anion is a bicarbonate ion, which has a negative charge due to its extra electron. Choice A is incorrect because a positive charge indicates a cation, not an anion. Choices C and D are also incorrect because chloride and sodium ions are both cations, not anions.

Question 10

An atom that has gained an electron is called:
A)an ion that is neutral
B)an ion with a charge of +1
C)an ion with a charge of -1
D)an atom with a charge of +1

Accepted Answer

When an atom gains an electron, it becomes negatively charged, meaning it now has more electrons than protons. This makes it an ion with a charge of -1. Therefore, option C is the correct answer.

Question 11

The bonds that hold the two chains of an insulin molecule together are:
A)disulfide bonds
B)peptide bonds
C)ionic bonds
D)protein bonds

Accepted Answer

The bonds that hold the two chains of an insulin molecule together are disulfide bonds. These covalent bonds form between two cysteine amino acids on each chain, creating a bridge that connects the two chains. Peptide bonds connect amino acids within a single chain, while ionic bonds and protein bonds are not involved in the structure of insulin.

Question 12

Disulfide bonds may be part of:
A)some starches
B)some proteins
C)DNA and RNA
D)true fats

Accepted Answer

Disulfide bonds are covalent bonds between two sulfur atoms in cysteine residues in proteins. These bonds help to stabilize the three-dimensional structure of proteins.

Question 13

Which statement is NOT true of ions?
A)An ion has either a positive or negative charge.
B)Atoms become ions by gaining or losing protons.
C)Ions with unlike charges are attracted to one another and form ionic bonds.
D)An atom that loses an electron will have a charge of +1.

Accepted Answer

Atoms become ions by gaining or losing electrons, not protons.

Question 14

Which statement is NOT true of ionic bonds?
A)They form salts.
B)In the solid state,they are very strong.
C)In water,many ionic bonds weaken.
D)They involve the sharing of electrons.

Accepted Answer

Ionic bonds involve the transfer of electrons, not the sharing of electrons.

Question 15

A cation has:
A)a positive charge,and an example is a chloride ion
B)a negative charge,and an example is a potassium ion
C)a positive charge,and an example is a calcium ion
D)a negative charge,and an example is an iron ion

Accepted Answer

A cation is an ion with a positive charge, which means that it has lost one or more electrons. Calcium ion is an example of a cation as it has lost two electrons, leaving it with a 2+ charge. Chloride ion (Option A) and Potassium ion (Option B) are examples of anions as they have negative charges. Iron ion (Option D) can be a cation or an anion depending on the number of electrons it has lost or gained.

Question 16

A bond in which electrons are shared between atoms is:
A)ionic
B)reciprocal
C)covalent
D)di-electron

Accepted Answer

In a covalent bond, electrons are shared between atoms. In an ionic bond, electrons are transferred from one atom to another. Reciprocal and di-electron are not terms used in chemical bonding.

Question 17

Dissociation of salts is important to:
A)free ions to take part in other reactions
B)produce energy
C)keep salt molecules stable in water
D)keep salt molecules stable as solids

Accepted Answer

Dissociation of salts involves the separation of the ions in the salt molecule, leading to free ions that can participate in other chemical reactions. This is important for the reactivity of the ions and for the formation of new compounds. Energy is not produced during dissociation, and dissociation does not stabilize the salt molecules either in water or as solids.

Question 18

Large molecules of glycogen are made of the smaller subunits called:
A)glucose
B)fatty acids and glycerol
C)amino acids
D)nucleotides

Accepted Answer

Large molecules of glycogen are made of the smaller subunits called glucose. Glycogen is a polysaccharide, which means it is a large molecule made up of many monosaccharide units (in this case, glucose).

Question 19

Which statement is NOT true of covalent bonds?
A)These bonds are not weakened when in water.
B)A molecule of water is formed by covalent bonds.
C)These bonds involve the sharing of electrons.
D)The atoms of most inorganic molecules are bonded by covalent bonds.

Accepted Answer

Covalent bonds involve the sharing of electrons between atoms, primarily in organic molecules, whereas inorganic molecules often have ionic or metallic bonds.

Question 20

A cation has:
A)a positive charge
B)a negative charge
C)a neutral charge
D)none of these,because the charge may vary

Accepted Answer

A cation is an ion with a positive charge. It is formed when an atom loses one or more electrons during a chemical reaction.

Quiz 2: Some Basic Chemistry

An atom of carbon has electrons to share to form bonds.

An anion has:

The term dissociation refers to:

A covalent bond is formed when:

The bonds that make water cohesive are:

Ionization of salts such as sodium chloride takes place:

A synonym for dissociation is:

The bonds that help maintain the three-dimensional shape of proteins and nucleic acids are:

An anion has:

An atom that has gained an electron is called:

The bonds that hold the two chains of an insulin molecule together are:

Disulfide bonds may be part of:

Which statement is NOT true of ions?

Which statement is NOT true of ionic bonds?

A cation has:

A bond in which electrons are shared between atoms is:

Dissociation of salts is important to:

Large molecules of glycogen are made of the smaller subunits called:

Which statement is NOT true of covalent bonds?

A cation has: