which statement accurately describes the periodic trends in atomic radius
Logo

Nursing Elites

ATI TEAS 7

TEAS 7 practice test free science

1. Which statement accurately describes the periodic trends in atomic radius?

Correct answer: A

Rationale: The correct statement is that atomic radius increases down a group and decreases across a period. When moving down a group, additional electron shells increase the distance from the nucleus, leading to larger atomic radii. On the other hand, when moving across a period, the number of electron shells remains constant, but the increasing nuclear charge pulls electrons closer, resulting in smaller radii. Choice B is incorrect because atomic radius does not decrease down a group and increase across a period. Choice C is incorrect because atomic radius does not remain constant; it exhibits specific trends. Choice D is incorrect because atomic radius follows predictable trends based on the periodic table structure, rather than fluctuating unpredictably.

2. What energy conversion occurs in a solar cell?

Correct answer: D

Rationale: Solar cells, also known as photovoltaic cells, convert solar energy from sunlight directly into electrical energy through a process called the photovoltaic effect. This process involves the absorption of photons from sunlight, which then generate an electric current. Choice A is incorrect because solar cells do not convert electrical energy into light energy. Choice B is incorrect as solar cells do not involve chemical energy conversion. Choice C is incorrect because solar cells do not primarily convert solar energy into thermal energy. Therefore, the correct answer is D) Solar energy to electrical energy.

3. What is the primary function of the epiglottis in the respiratory system?

Correct answer: C

Rationale: The primary function of the epiglottis in the respiratory system is to prevent food from entering the trachea. During swallowing, the epiglottis covers the opening of the trachea, guiding food down the esophagus to the stomach and preventing it from entering the airway. This mechanism safeguards the respiratory system from foreign objects, ensuring proper air passage and avoiding potential choking hazards. Choices A, B, and D are incorrect: A) Filtration of air is mainly performed by the nasal hairs and the mucous membranes of the respiratory tract. B) Production of mucus is primarily carried out by the mucous glands in the respiratory system to trap particles and humidify the air. D) Oxygen exchange in the alveoli occurs in the lungs and is related to the process of respiration, not the function of the epiglottis.

4. What is the net ionic equation for the reaction: 2HCl(aq) + Ba(OH)2(aq) → 2H2O(l) + BaCl2(aq)?

Correct answer: A

Rationale: In the given reaction, the complete ionic equation is: 2H+(aq) + 2Cl-(aq) + Ba2+(aq) + 2OH-(aq) → 2H2O(l) + Ba2+(aq) + 2Cl-(aq). Spectator ions (Ba2+ and Cl-) do not participate in the net ionic equation, which simplifies to: 2H+(aq) + 2OH-(aq) → 2H2O(l). This equation represents the significant species involved in the reaction, showcasing the formation of water from the combination of hydrogen ions and hydroxide ions, resulting in the production of water molecules.

5. In the context of optical fibers, chromatic dispersion refers to:

Correct answer: B

Rationale: Chromatic dispersion in optical fibers refers to the spreading of light pulses due to different colors (wavelengths) traveling at slightly different speeds. This phenomenon can cause the different components of a light pulse to arrive at the receiver at slightly different times, leading to signal distortion. Choice A is incorrect because total internal reflection refers to the phenomenon where light is reflected back into the medium it originated from when hitting the boundary at an angle greater than the critical angle. Choice C is incorrect as it describes the principle of light being guided within an optical fiber through total internal reflection at the core-cladding interface. Choice D is incorrect as the absorption of light by the fiber material does not relate to chromatic dispersion.

Similar Questions

Which part of the brain regulates body temperature, hunger, and thirst?
What property of a substance refers to its ability to undergo a chemical change and form new substances?
Which part of the brain is responsible for controlling voluntary muscle movements?
What is the feedback mechanism in the endocrine system that helps maintain hormone balance?
During normal breathing, which muscle is the primary driver of inhalation by contracting and flattening to increase the volume of the thoracic cavity?

Access More Features

ATI TEAS Premium Plus
$149.99/ 90 days

  • Actual ATI TEAS 7 Questions
  • 3,000 questions with answers
  • 90 days access

ATI TEAS Basic
$99/ 30 days

  • 3,000 Questions with answers
  • 30 days access

Other Courses