JMU BIO 140 REVIEW EXAMS TIPS QUESTIONS
AND ANSWERS SURE A+
✔✔Define electronegativity - ✔✔Atom's ability to attract and hold electrons
✔✔The bigger difference in electronegativity means the _________ polar - ✔✔more
✔✔Finding electronegativity - ✔✔
✔✔Electronengative atoms will have a __________ negative charge - ✔✔partial
✔✔Define hydrogen bond - ✔✔weak "attraction" between electronegative atom and a
hydrogen bonded to an electronegative atom
✔✔What bond forms between two water molecules? - ✔✔hydrogen bonds
✔✔What bonds holds oxygen and hydrogen together? - ✔✔covalent bonds
✔✔What happens when water freezes? - ✔✔it becomes less dense
✔✔What allows water to resist temperature change? - ✔✔hydrogen bonds
, ✔✔Why does water not evaporate easily? - ✔✔high boiling temperature
✔✔Water is a ______ solvent. - ✔✔universal
✔✔Why is water a universal solvent? - ✔✔polarity allows for other polar or fully charged
molecules to dissolve in water
✔✔What makes water cohesive? - ✔✔hydrogen bonds together are strong and allows
surface tension
✔✔Define ionic bond - ✔✔Formed when electrons are transferred from one atom to
another and for ions
✔✔Ionic bonds in a biological system are very _________ - ✔✔weak
✔✔Define hydrophobic - ✔✔does not mix with water
✔✔Why does hydrophobic molecules aggregate? - ✔✔to minimize exposure to polar
substances
✔✔Define Van der Waals forces - ✔✔weak attraction between atoms due to electron
asymmetries
✔✔What is an importance of Van der Waals forces? - ✔✔hold fatty acid tails together
✔✔Is an ionic bond partial or full charge? - ✔✔full charge
✔✔Is an hydrogen bond partial or full charge? - ✔✔partial
✔✔Is an Van der Wall partial or full charge? - ✔✔partial
✔✔The more acidic, the ______ the pH - ✔✔lower
✔✔The more basic, the ______ the pH - ✔✔higher
✔✔pH = ? - ✔✔-log[H+]
✔✔pH and [H+] are ________ related - ✔✔inversely
✔✔How much is one mole of H+? - ✔✔6.02x10^23 H+
✔✔How do you calculate the difference in H+? - ✔✔divide the higher H+ by the lower
H+
AND ANSWERS SURE A+
✔✔Define electronegativity - ✔✔Atom's ability to attract and hold electrons
✔✔The bigger difference in electronegativity means the _________ polar - ✔✔more
✔✔Finding electronegativity - ✔✔
✔✔Electronengative atoms will have a __________ negative charge - ✔✔partial
✔✔Define hydrogen bond - ✔✔weak "attraction" between electronegative atom and a
hydrogen bonded to an electronegative atom
✔✔What bond forms between two water molecules? - ✔✔hydrogen bonds
✔✔What bonds holds oxygen and hydrogen together? - ✔✔covalent bonds
✔✔What happens when water freezes? - ✔✔it becomes less dense
✔✔What allows water to resist temperature change? - ✔✔hydrogen bonds
, ✔✔Why does water not evaporate easily? - ✔✔high boiling temperature
✔✔Water is a ______ solvent. - ✔✔universal
✔✔Why is water a universal solvent? - ✔✔polarity allows for other polar or fully charged
molecules to dissolve in water
✔✔What makes water cohesive? - ✔✔hydrogen bonds together are strong and allows
surface tension
✔✔Define ionic bond - ✔✔Formed when electrons are transferred from one atom to
another and for ions
✔✔Ionic bonds in a biological system are very _________ - ✔✔weak
✔✔Define hydrophobic - ✔✔does not mix with water
✔✔Why does hydrophobic molecules aggregate? - ✔✔to minimize exposure to polar
substances
✔✔Define Van der Waals forces - ✔✔weak attraction between atoms due to electron
asymmetries
✔✔What is an importance of Van der Waals forces? - ✔✔hold fatty acid tails together
✔✔Is an ionic bond partial or full charge? - ✔✔full charge
✔✔Is an hydrogen bond partial or full charge? - ✔✔partial
✔✔Is an Van der Wall partial or full charge? - ✔✔partial
✔✔The more acidic, the ______ the pH - ✔✔lower
✔✔The more basic, the ______ the pH - ✔✔higher
✔✔pH = ? - ✔✔-log[H+]
✔✔pH and [H+] are ________ related - ✔✔inversely
✔✔How much is one mole of H+? - ✔✔6.02x10^23 H+
✔✔How do you calculate the difference in H+? - ✔✔divide the higher H+ by the lower
H+
