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BCHM 307 Exam 1 Purdue 2025/2026
Exam Questions and Detailed Answers |
Get it 100% Correct Answers
Name the four types of small biological molecules. Which three are capable of
forming polymeric structures? What are the names of the polymeric structures that
are formed? - 🧠 ANSWER ✔✔4 types of biological molecules: amino acids,
nucleotides, monosaccharides, lipids
3 capable of forming polymeric strucures: amino acids, monosccharides, and
nucleotides
Names of polymeric structures formed: proteins, carbohydrates, nucleic acids
A healthy diet must include some protein. Assuming you had a way to measure the
amount of each element in a sample of food, which element would you measure in
order to tell whether the food contained protein? - 🧠 ANSWER ✔✔Assuming you
had a way to measure each element in a food sample, you should measure for the
element nitrogen if determining the amount of protein. Protein is the only
macronutrient that contains nitrogen.
1
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Which has the greater entropy, a polymeric molecule or a mixture of its constituent
monomers? - 🧠 ANSWER ✔✔The polymeric molecule is much more ordered
compared to a mixture of its constituent monomers. This order results in less
entropy. A constituent monomer may have multiple arrangements which results in
greater entropy.
A soccer coach keeps a couple of instant cold packs in her bag in case one of her
players suffers a muscle injury. Instant cold packs are composed of a plastic bag
containing a smaller water bag and solid ammonium nitrate. In order to activate the
cold pack, the bag is kneaded until the smaller water bag breaks, which allows the
released water to dissolve the ammonium nitrate. the equation for the dissolution of
ammonium nitrate in water is shown below. How does the cold pack work. - 🧠
ANSWER ✔✔The positive charge indicates that the dissolution of ammonium
nitrate is an endothermic process. When the ammonium nitrates dissolves in water,
it absorbs heat from its surroundings, making its surroundings cooler, making it
useable is a cold pack for injuries.
Which compound has a higher boiling point, H2O or H2S? Explain. - 🧠 ANSWER
✔✔Although both have the same geometry and can form H bonds, the H bonds of
water are stronger. The electronegativity between H and O is greater than between
2
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H and S, resulting in a greater difference in partial charges on the atoms in the
water molecule.
Explain why water forms nearly spherical droplets on the surface of a freshly
waxed car. Why doesn't water bead on a clean windshield. - 🧠 ANSWER
✔✔Water is hydrophilic, so when exposed to a hydrophobic surface, water will try
minimize its exposure to that surface, which is why it beads in the shape of a
spherical droplet on a waxed car. However when a water is exposed to a
hydrophilic surface in which it can interact, such as a clean windshield, it will
spread out.
Several hours after a meal, partially digested food leaves the stomach and enters
the small intestine, where pancreatic juice is added. How does the pH of the
partially digested mixture change as it passes from the stomach into the intestine? -
🧠 ANSWER ✔✔The partially digested food has a low pH until the pancreatic
juices are added. The pancreatic juice is nearly alkaline and therefore will increase
the pH of the partially digested food.
In 1952, Alfred Hershey and Martha Chase carried out experiments using
bacteriophages, which consist of nucleic acid enclosed by a protein capsid (coat).
They first labeled the bacteriophages with the radioactive isotopes and . Because
proteins contain sulfur but not phosphorus, and DNA contains phosphorus but not
3
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
BCHM 307 Exam 1 Purdue 2025/2026
Exam Questions and Detailed Answers |
Get it 100% Correct Answers
Name the four types of small biological molecules. Which three are capable of
forming polymeric structures? What are the names of the polymeric structures that
are formed? - 🧠 ANSWER ✔✔4 types of biological molecules: amino acids,
nucleotides, monosaccharides, lipids
3 capable of forming polymeric strucures: amino acids, monosccharides, and
nucleotides
Names of polymeric structures formed: proteins, carbohydrates, nucleic acids
A healthy diet must include some protein. Assuming you had a way to measure the
amount of each element in a sample of food, which element would you measure in
order to tell whether the food contained protein? - 🧠 ANSWER ✔✔Assuming you
had a way to measure each element in a food sample, you should measure for the
element nitrogen if determining the amount of protein. Protein is the only
macronutrient that contains nitrogen.
1
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
,2
Which has the greater entropy, a polymeric molecule or a mixture of its constituent
monomers? - 🧠 ANSWER ✔✔The polymeric molecule is much more ordered
compared to a mixture of its constituent monomers. This order results in less
entropy. A constituent monomer may have multiple arrangements which results in
greater entropy.
A soccer coach keeps a couple of instant cold packs in her bag in case one of her
players suffers a muscle injury. Instant cold packs are composed of a plastic bag
containing a smaller water bag and solid ammonium nitrate. In order to activate the
cold pack, the bag is kneaded until the smaller water bag breaks, which allows the
released water to dissolve the ammonium nitrate. the equation for the dissolution of
ammonium nitrate in water is shown below. How does the cold pack work. - 🧠
ANSWER ✔✔The positive charge indicates that the dissolution of ammonium
nitrate is an endothermic process. When the ammonium nitrates dissolves in water,
it absorbs heat from its surroundings, making its surroundings cooler, making it
useable is a cold pack for injuries.
Which compound has a higher boiling point, H2O or H2S? Explain. - 🧠 ANSWER
✔✔Although both have the same geometry and can form H bonds, the H bonds of
water are stronger. The electronegativity between H and O is greater than between
2
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
, 3
H and S, resulting in a greater difference in partial charges on the atoms in the
water molecule.
Explain why water forms nearly spherical droplets on the surface of a freshly
waxed car. Why doesn't water bead on a clean windshield. - 🧠 ANSWER
✔✔Water is hydrophilic, so when exposed to a hydrophobic surface, water will try
minimize its exposure to that surface, which is why it beads in the shape of a
spherical droplet on a waxed car. However when a water is exposed to a
hydrophilic surface in which it can interact, such as a clean windshield, it will
spread out.
Several hours after a meal, partially digested food leaves the stomach and enters
the small intestine, where pancreatic juice is added. How does the pH of the
partially digested mixture change as it passes from the stomach into the intestine? -
🧠 ANSWER ✔✔The partially digested food has a low pH until the pancreatic
juices are added. The pancreatic juice is nearly alkaline and therefore will increase
the pH of the partially digested food.
In 1952, Alfred Hershey and Martha Chase carried out experiments using
bacteriophages, which consist of nucleic acid enclosed by a protein capsid (coat).
They first labeled the bacteriophages with the radioactive isotopes and . Because
proteins contain sulfur but not phosphorus, and DNA contains phosphorus but not
3
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
