Fundamentals of Conceptual Chemistry Final Exam Review

When an electron is transferred from one atom to another, that causes them to have opposing charges. This is an example of which type of bond?

• Ionic bond

• Covalent bond

• Hydrogen bond

• Metallic bond

Answer explanation

When an electron is transferred between atoms, it creates ions with opposite charges, leading to an ionic bond. This bond forms due to the electrostatic attraction between the positively and negatively charged ions.

Tags

NGSS.MS-PS1-5

What type of ion forms when an atom loses electrons?

• Cation

• Anion

• Isotope

• Radical

Answer explanation

When an atom loses electrons, it becomes positively charged, forming a cation. In contrast, gaining electrons results in anions, while isotopes and radicals refer to different atomic properties.

A bond formed by the attraction between positively charged metals ions and the electrons around them is a(n) ________.

• Metallic bond

• Ionic bond

• Covalent bond

• Hydrogen bond

Answer explanation

A metallic bond is formed by the attraction between positively charged metal ions and the delocalized electrons surrounding them, allowing for conductivity and malleability, distinguishing it from ionic, covalent, and hydrogen bonds.

Tags

NGSS.HS-PS1-3

When you shake sugar and sand together in a test tube, they form a ________.

• Mixture

• Compound

• Element

• Solution

Answer explanation

When sugar and sand are shaken together, they do not chemically react but simply combine physically, forming a mixture. Each substance retains its properties, distinguishing it from a compound or solution.

Tags

NGSS.MS-PS1-2

What type of bond holds one H2O (water) molecule together, giving it opposing charges?

• Polar covalent bond

• Ionic bond

• Hydrogen bond

• Metallic bond

Answer explanation

A water molecule (H2O) has a polar covalent bond, where oxygen is more electronegative than hydrogen, creating partial positive and negative charges. This polarity is responsible for water's unique properties.

Tags

NGSS.MS-PS1-1

Rusting is a ________ change.

• Chemical

• Physical

• Reversible

• Temporary

Answer explanation

Rusting is a chemical change because it involves a reaction between iron, oxygen, and moisture, resulting in the formation of rust (iron oxide). This process alters the chemical composition of the iron, making it irreversible.

Tags

NGSS.MS-PS1-5

What indicates a change in the state of matter?

• Temperature change (or heat transfer)

• Color change

• Change in shape only

• Increase in mass

Answer explanation

A change in temperature (or heat transfer) indicates a change in the state of matter, such as melting or boiling. Other options like color change or mass increase do not directly signify a state change.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

The structure of an atom is shown below. Which element is the atom an isotope of?

• Hydrogen

• Helium

• Carbon

• Oxygen

Answer explanation

The atom is an isotope of Carbon because it has 6 protons and a different number of neutrons, which is characteristic of isotopes. Hydrogen, Helium, and Oxygen have different atomic structures.

Tags

NGSS.MS-PS1-1

Which of the following is true about comparing both nitrogen and phosphorus?

• Both are essential nutrients for plants.

• Only nitrogen is found in the atmosphere as a gas.

• Phosphorus cycles through the atmosphere like nitrogen.

• Neither is important for living organisms.

Answer explanation

Both nitrogen and phosphorus are essential nutrients for plants, playing crucial roles in growth and development. Nitrogen is abundant in the atmosphere, while phosphorus is primarily found in soil, not cycling through the atmosphere like nitrogen.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

The formula to calculate density is:

• mass/volume

• volume/mass

• mass x volume

• mass + volume

Answer explanation

The correct formula to calculate density is mass divided by volume (mass/volume). This relationship shows how much mass is contained in a given volume, making it the accurate choice among the options.