TEAS 7 Chemistry: Essential Practice for Success

ATI TEAS 7

Chemistry

1. How many moles of oxygen are required to completely react with 5 moles of propane (C3H8) in the combustion reaction?

A. 5 moles
B. 10 moles
C. 15 moles
D. 20 moles

Correct answer: b

Rationale: The balanced equation is C3H8 + 5O2 â†’ 3CO2 + 4H2O, indicating a 5:10 ratio between moles of oxygen and moles of propane.

2. A medication order is for 250 micrograms of a drug to be administered subcutaneously. The available syringe measures in milliliters. How many milliliters should the nurse draw up?

A. 0.00025 milliliters
B. 0.0025 milliliters
C. 0.025 milliliters
D. 0.25 milliliters

Correct answer: B

Rationale: First convert micrograms to milliliters, knowing 1000 micrograms equal 1 milliliter. Divide the desired dosage (250 micrograms) by the conversion factor (1000 micrograms/milliliter) to find the volume needed: 250 micrograms / 1000 micrograms/milliliter = 0.00025 milliliters. However, drawing such a small volume might be inaccurate, so round to the nearest practical measurement, which is 0.0025 milliliters.

3. What is the purpose of the periosteum, the tough outer layer of bone?

A. Produces red blood cells
B. Provides protection and nourishment to bone
C. Forms the joint surface
D. Stores minerals

Correct answer: B

Rationale: The correct answer is B: 'Provides protection and nourishment to bone.' The periosteum is a tough outer layer of bone that serves multiple functions. It provides protection by acting as a barrier against infections and injuries. Additionally, the periosteum contains blood vessels that supply nutrients to the bone cells, aiding in bone growth, repair, and maintenance. While red blood cells are produced in the bone marrow, not in the periosteum, the periosteum's primary role is to support the overall health and integrity of the bone structure.

4. What is the main difference between a telescope and a microscope?

A. Telescopes magnify distant objects, while microscopes magnify small objects.
B. Telescopes use lenses, while microscopes use mirrors.
C. Telescopes collect light, while microscopes emit light.
D. They both magnify objects but serve different purposes.

Correct answer: A

Rationale: While both instruments magnify objects, telescopes are designed to observe distant objects, while microscopes are used to magnify tiny objects close to the observer.

5. Which of the following is NOT a greenhouse gas?

A. Carbon Dioxide
B. Methane
C. Oxygen
D. Water Vapor

Correct answer: C

Rationale: Rationale: A) Carbon Dioxide: Carbon dioxide is a greenhouse gas that is released into the atmosphere through various human activities such as burning fossil fuels and deforestation. B) Methane: Methane is another greenhouse gas that is released from sources like livestock, landfills, and natural gas production. C) Oxygen: Oxygen is not considered a greenhouse gas. It is a vital component of the Earth's atmosphere that is necessary for respiration and combustion. D) Water Vapor: Water vapor is also a greenhouse gas that plays a significant role in the Earth's climate system by trapping heat in the atmosphere. Therefore, the correct answer is C) Oxygen, as it is not a greenhouse gas.