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NLN PAX SCIENCE VERSION 4 (NEW 2025/
2026 UPDATE) QUESTIONS & ANSWERS| GRADE
A| 100% CORRECT (VERIFIED SOLUTIONS)
1. If the medulla of the brain in a human was damaged, which of
these conditions would most likely result?
-Inability to remember.
-Difficulty in breathing.
-Inability to speak.
-Blurred vision.: Difficulty in breathing.
2. In ecological succession, the first living thing to colonize a
hitherto barren area is called a -producer.
-primary consumer.
-pioneer organism.
-carnivore.: pioneer organism.
3. Night blindness in humans is caused by a lack of -Vitamin A.
-Niacin.
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-Calcium.
-Vitamin D.: Vitamin A.
4. To sterilize a metal probe in the office, a dentist could use a
steam sterilizer. If unavailable, the next most effective method
to sterilize the instrument would be
-boiling it in water for 15 minutes.
-dipping it into a concentrated acid solution.
-heating it in a hot air oven at 160°C for 20 minutes.
-washing it in soap and water.: boiling it in water for 15 minutes.
5. In varieties of matter, the term heterogeneous may be applied
to -elements, but not compounds.
-compounds, but not elements.
-compounds and elements, but not mixtures.
-mixtures, but not elements or compounds.: mixtures, but not
elements or compounds.
6. Which of these organisms use nitrogen directly from the air?
-Blue-green algae.
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-Protozoa.
-Plants.
-Worms.: Blue-green algae.
7. Iodized salt is used to prevent a human condition known as -
rickets. -goiter.
-scurvy.
-beri-beri.: goiter.
8. The atoms of an element with seven valence electrons are
most probably classified as -metals.
-nonmetals.
-metalloids.
-noble gases.: nonmetals.
9. The organ that filters metabolic waste from the blood is the -
small intestine.
-liver.
-kidney.
-stomach.: kidney.
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10. Which of these equations best illustrates a synthesis
reaction?
-2Na + Cl2 -> 2NaCl
-NaOH + HCl -> NaCl + H2O
-2H2O2 -> 2H2O + O2
-CH4 + 2O2 -> CO2 + 2H2O: 2Na + Cl2 -> 2NaCl
11. Which of these hydrocarbons is a member of the benzene
family?
-Toluene.
-Ethyne.
-Propanone.
-Methanol.: Toluene.
12. Which of these quantities is a vector quantity?
-Force.
-Mass.
-Energy.
-Time.: Force. (Energy? Scalar quantity)
NLN PAX
NLN PAX
NLN PAX SCIENCE VERSION 4 (NEW 2025/
2026 UPDATE) QUESTIONS & ANSWERS| GRADE
A| 100% CORRECT (VERIFIED SOLUTIONS)
1. If the medulla of the brain in a human was damaged, which of
these conditions would most likely result?
-Inability to remember.
-Difficulty in breathing.
-Inability to speak.
-Blurred vision.: Difficulty in breathing.
2. In ecological succession, the first living thing to colonize a
hitherto barren area is called a -producer.
-primary consumer.
-pioneer organism.
-carnivore.: pioneer organism.
3. Night blindness in humans is caused by a lack of -Vitamin A.
-Niacin.
NLN PAX
, 2
NLN PAX
-Calcium.
-Vitamin D.: Vitamin A.
4. To sterilize a metal probe in the office, a dentist could use a
steam sterilizer. If unavailable, the next most effective method
to sterilize the instrument would be
-boiling it in water for 15 minutes.
-dipping it into a concentrated acid solution.
-heating it in a hot air oven at 160°C for 20 minutes.
-washing it in soap and water.: boiling it in water for 15 minutes.
5. In varieties of matter, the term heterogeneous may be applied
to -elements, but not compounds.
-compounds, but not elements.
-compounds and elements, but not mixtures.
-mixtures, but not elements or compounds.: mixtures, but not
elements or compounds.
6. Which of these organisms use nitrogen directly from the air?
-Blue-green algae.
NLN PAX
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NLN PAX
-Protozoa.
-Plants.
-Worms.: Blue-green algae.
7. Iodized salt is used to prevent a human condition known as -
rickets. -goiter.
-scurvy.
-beri-beri.: goiter.
8. The atoms of an element with seven valence electrons are
most probably classified as -metals.
-nonmetals.
-metalloids.
-noble gases.: nonmetals.
9. The organ that filters metabolic waste from the blood is the -
small intestine.
-liver.
-kidney.
-stomach.: kidney.
NLN PAX
, 4
NLN PAX
10. Which of these equations best illustrates a synthesis
reaction?
-2Na + Cl2 -> 2NaCl
-NaOH + HCl -> NaCl + H2O
-2H2O2 -> 2H2O + O2
-CH4 + 2O2 -> CO2 + 2H2O: 2Na + Cl2 -> 2NaCl
11. Which of these hydrocarbons is a member of the benzene
family?
-Toluene.
-Ethyne.
-Propanone.
-Methanol.: Toluene.
12. Which of these quantities is a vector quantity?
-Force.
-Mass.
-Energy.
-Time.: Force. (Energy? Scalar quantity)
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