TEAS 7 Chemistry: Essential Practice for Success

ATI TEAS 7

Chemistry

1. What is the mass number of an element?

A. The number of protons in an atom's nucleus.
B. The number of neutrons in an atom's nucleus.
C. The number of electrons in an atom's valence shell.
D. The number of isotopes of an element.

Correct answer: B

Rationale: The mass number of an element is the total number of protons and neutrons in the nucleus of an atom. It is represented by the symbol A and is written as a superscript to the element's symbol. For example, the mass number of carbon-12 is 12, which means that a carbon-12 atom has 6 protons and 6 neutrons in its nucleus.

2. Rectangle: A picture frame measures 15cm by 20cm. What is its perimeter?

A. 30cm
B. 55cm
C. 65cm
D. 75cm

Correct answer: C

Rationale: Add the lengths of all sides: perimeter = 2 (length + width) = 2 (15cm + 20cm) = 65cm.

3. Edema is a condition characterized by swelling caused by a buildup of lymph fluid. What factors can contribute to edema?

A. Regular exercise
B. Maintaining a healthy weight
C. Poor circulation or blockage in the lymphatic system
D. Proper hydration

Correct answer: C

Rationale: Edema is a condition where there is an abnormal accumulation of fluid in the body tissues, leading to swelling. Poor circulation or blockage in the lymphatic system can contribute to edema by hindering the proper drainage of lymph fluid. When the lymphatic system is not functioning efficiently, it can result in fluid retention and swelling in the affected areas. Regular exercise and maintaining a healthy weight can actually help improve circulation and lymphatic flow, reducing the risk of edema. Proper hydration is important for overall health but specifically does not directly contribute to the development of edema as poor circulation or lymphatic blockages do.

4. What is the relationship between the frequency and period of a wave?

A. They are unrelated
B. Frequency = Period
C. Frequency = 1/Period
D. Period = 1/Frequency

Correct answer: D

Rationale: The correct relationship between frequency and period of a wave is that Period = 1/Frequency. This means that the period of a wave is the reciprocal of its frequency. Frequency is the number of complete cycles of a wave that occur in a unit of time, while the period is the time it takes for one complete cycle of the wave to occur. Since frequency and period are inversely related, the correct formula is Period = 1/Frequency.

5. The energy required to break a chemical bond is called:

A. Kinetic energy
B. Potential energy
C. Activation energy
D. Bond energy

Correct answer: C

Rationale: Rationale: Activation energy is the energy required to break a chemical bond and initiate a chemical reaction. Kinetic energy (option A) is the energy of motion, potential energy (option B) is stored energy, and bond energy (option D) is the energy required to break a particular chemical bond in a molecule. Among the options provided, activation energy best describes the energy required to break a chemical bond.