what is the periodic law

ATI TEAS 7

TEAS 7 practice test free science

1. What is the periodic law?

A. The statement that the properties of the elements are a periodic function of their atomic numbers.
B. The statement that elements can be arranged in a table where elements with similar properties are grouped together.
C. The statement that elements can be arranged in a table where the atomic number of an element is equal to the number of protons in its nucleus.
D. The statement that elements can be arranged in a table where the atomic mass of an element is equal to the number of neutrons in its nucleus.

Correct answer: A

Rationale: The periodic law states that the properties of elements are a periodic function of their atomic numbers. This means that when elements are arranged in order of increasing atomic number, there is a periodic repetition of their properties. This forms the basis for the modern periodic table. Option B describes the organization of elements in the periodic table, which is related to the periodic law but not the definition of it. Options C and D are incorrect as they describe concepts related to atomic structure (atomic number and atomic mass) rather than the periodic law itself.

2. What is the difference between exhalation (expiration) and inhalation (inspiration)?

A. Exhalation involves active muscle contraction, while inhalation is passive.
B. Inhalation brings in oxygen-rich air, while exhalation releases carbon dioxide-rich air.
C. Exhalation occurs through the nose only, while inhalation can occur through the nose or mouth.
D. Inhalation warms and humidifies air, while exhalation cools and dries air.

Correct answer: A

Rationale: Exhalation (expiration) involves active muscle contraction, specifically the diaphragm and intercostal muscles, to decrease the volume of the thoracic cavity and push air out of the lungs. In contrast, inhalation (inspiration) is a passive process where the diaphragm and external intercostal muscles contract to increase the thoracic cavity volume, allowing air to flow into the lungs. Choice B is incorrect as exhalation removes carbon dioxide-rich air and inhalation brings in oxygen-rich air. Choice C is incorrect because both exhalation and inhalation can occur through the nose or mouth. Choice D is inaccurate as inhalation humidifies and warms the air, while exhalation cools and dries it.

3. The ureters are paired tubes that transport urine from the:

A. Bladder to the urethra
B. Kidneys to the bladder
C. Urethra to the kidneys
D. Skin to the kidneys

Correct answer: B

Rationale: The ureters are responsible for carrying urine from the kidneys to the bladder. Once urine is produced in the kidneys, it travels down the ureters to be stored in the bladder until it is eliminated from the body through the urethra. Therefore, the correct answer is B, 'Kidneys to the bladder.' Choices A, C, and D are incorrect as they do not accurately describe the function of the ureters in the urinary system. Choice A, 'Bladder to the urethra,' is incorrect because the ureters carry urine from the kidneys to the bladder, not from the bladder to the urethra. Choice C, 'Urethra to the kidneys,' is incorrect as the flow of urine is from the kidneys to the bladder via the ureters, not in the reverse direction. Choice D, 'Skin to the kidneys,' is unrelated to the urinary system; the ureters are not involved in transporting substances from the skin to the kidneys.

4. Which of the following is a condition characterized by a loss of bone density and increased risk of fractures?

A. Osteoarthritis
B. Rickets
C. Osteoporosis
D. Scoliosis

Correct answer: C

Rationale: Osteoporosis is a condition characterized by a loss of bone density, leading to fragile bones and an increased risk of fractures. Osteoarthritis is a degenerative joint disease affecting cartilage, Rickets is caused by a deficiency in vitamin D leading to impaired bone development, and Scoliosis is an abnormal sideways curvature of the spine. Therefore, the correct answer is osteoporosis as it specifically pertains to decreased bone density and fracture risk, distinguishing it from the other conditions listed.

5. Which property of a substance resists a change in its shape?

A. Density
B. Mass
C. Inertia
D. Elasticity

Correct answer: D

Rationale: Elasticity refers to a material's ability to resist deformation and return to its original shape after stress is applied. It is the property that resists a change in shape. Density is the mass per unit volume of a substance. Mass is the amount of matter in an object, while inertia is the tendency of an object to resist changes in its state of motion. Viscosity, not mentioned in the question, is the resistance of a fluid to flow, not shape change.