Covalent Bonds and Molecular Properties

What is Golden Rice genetically engineered to produce?

• Vitamin C

• Beta-carotene

• Protein

• Sugar

What is a characteristic of a conjugated compound?

• It has only single carbon bonds.

• It has alternating single and double carbon bonds.

• It has only double carbon bonds.

• It has triple carbon bonds.

What happens in a covalent bond?

• Atoms transfer electrons to each other.

• Atoms share a pair of electrons.

• Atoms become oppositely charged ions.

• Atoms repel each other completely.

Which type of molecular orbital has lower energy?

• Antibonding orbitals

• Non-bonding orbitals

• Bonding orbitals

• Hybrid orbitals

Which statement accurately describes the relationship between energy and stability in molecular orbitals?

• Higher energy molecular orbitals are more stable.

• Lower energy molecular orbitals are more stable.

• Energy and stability are unrelated in molecular orbitals.

• All molecular orbitals have the same stability.

What happens to an electron in a conjugated molecule when it absorbs ultraviolet (UV) light?

• It breaks the chemical bonds in the molecule.

• It jumps from a lower energy occupied orbital to a higher energy unoccupied orbital.

• It causes the molecule to change its physical state.

• It makes the molecule emit visible light.

What does the Beer-Lambert Law (A = εcl) allow scientists to determine about a sample using UV spectroscopy?

• The molecular weight of the sample.

• The boiling point of the sample.

• The concentration of the conjugated molecule in the sample.

• The exact chemical structure of the sample.

Why does beta-carotene appear orange to our eyes?

• It reflects all colors of light equally.

• It absorbs orange wavelengths of light.

• It absorbs blue and violet wavelengths of light, allowing orange to be seen.

• It emits orange light after absorbing other wavelengths.