Chemical Bonds Exam

Copper, sulfur, and oxygen are examples of ______.

Answer explanation

Copper, sulfur, and oxygen are all elements found on the periodic table. They are not compounds (which consist of two or more elements chemically combined), mixtures (which are physical combinations), or colloids.

Tags

NGSS.MS-PS1-1

A chemical ______ tells what elements a compound contains and the exact number of the atoms of each element in a unit of that compound.

Answer explanation

The correct answer is 'formula' because a chemical formula specifies the elements in a compound and the number of atoms of each element, providing a precise representation of the compound's composition.

Tags

NGSS.MS-PS1-1

H₂O is also known as ______.

Answer explanation

H₂O is the chemical formula for water, which is its common name. The other options, carbon, mercury, and nickel, are different substances and do not correspond to H₂O.

A chemical ______ is the force that holds atoms together in a compound.

Answer explanation

A chemical bond is the force that holds atoms together in a compound. Elements are the basic substances, compounds are combinations of elements, and formulas represent the composition, but the bond is the key force.

A charged particle is known as a(n) ______.

Answer explanation

A charged particle is called an ion. Ions are formed when atoms gain or lose electrons, resulting in a net electric charge. Plasma is a state of matter that contains ions, but the term specifically refers to charged particles as ions.

Tags

NGSS.MS-PS2-3

A covalent bond is the force of attraction between the opposite charges of the ions in an ionic compound.

• True

• False

Answer explanation

The statement is false because a covalent bond involves the sharing of electrons between atoms, while ionic bonds are formed by the attraction between oppositely charged ions.

A neutral particle that forms as the result of electron sharing is called an ion.

• True

• False

Answer explanation

The statement is false because a neutral particle formed by electron sharing is called a molecule, not an ion. Ions are charged particles resulting from the loss or gain of electrons.

A polar molecule is one in which electrons are shared equally in bonds.

• True

• False

Answer explanation

A polar molecule has an unequal sharing of electrons, leading to partial charges. Therefore, the statement that electrons are shared equally in bonds is false.

Tags

NGSS.MS-PS1-1

Contrast a single covalent bond with a triple covalent bond. Answer the following questions using complete sentences.

Answer explanation

A single covalent bond involves the sharing of one pair of electrons between two atoms, while a triple covalent bond involves the sharing of three pairs of electrons. This makes triple bonds stronger and shorter than single bonds.

Contrast the terms hydrated and anhydrous. Answer the following questions using complete sentences.

Answer explanation

Hydrated refers to compounds that contain water molecules within their structure, while anhydrous refers to compounds that do not contain water. Thus, hydrated substances are associated with water, whereas anhydrous substances are dry.