Which of the following is the correct functional group for alcohols?
A. -COOH
B. -CH3
C. -OH
D. -SH
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Isomers have the ____ chemical formula, _____ chemical structures and _____ biological functions.
A. different, different, same
B. same, different, different
C. same, different, same
D. different, same, same
Carbon can form up to four covalent bonds because --
A. it has four valence electrons.
B. it is a polar molecule.
C. it bonds to hydrogens, which are small.
D. it has a greater electronegativity than most other elements.
Which statement best describes hydrogen bonding?
A. a covalent bond that occurs when an negatively charged oxygen donates an electron to a positively charged hydrogen
B. an ionic bond that occurs when a hydrogen shares its lone electron with an oxygen or nitrogen
C. an attactive force between the partial positive charge on a hydrogen and a partial negative charge on an oxygen or nitrogen
D. an attactive force between the partial negative charge on a hydrogen and a partial positive charge on an oxygen or nitrogen
Water has unique properties that allow it to support life. Which of the following best describes this?
A. Water is a non-polar molecule because oxygen and hydrogen share electrons equally, which allows for hydrogen bonding.
B. Water is a polar molecule because oxygen and hydrogen form polar covalent bonds, which allows for hydrogen bonding.
C. Water covalently bonds with other water molecules, which is the strongest form of bonds.
D. Water forms ionic bonds with other water molecules, which allows it to break bonds easily.
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