TEAS version 7 quizlet science

Correct Answer: A

Rationale: The correct answer is A: 'Number of elements.' In a balanced chemical equation, coefficients represent the ratio of moles of each species involved in the reaction. They indicate the relative number of molecules or formula units of each compound taking part in the reaction. Choice B, 'Ratio of reactants and products,' is incorrect because the coefficients in a balanced equation do not represent the ratio of reactants and products directly, but rather the stoichiometry of the reaction. Choice C, 'Physical state of the substances,' is incorrect because the physical states (solid, liquid, gas, or aqueous) are denoted with symbols next to the chemical formula, not the coefficients. Choice D, 'Rate of the reaction,' is incorrect as coefficients in a balanced equation do not provide information about the rate of the reaction, which is determined by factors like temperature, concentration, and catalysts.

Correct Answer: C

Rationale: The potential energy stored in a spring is given by the formula \(PE = \frac{1}{2}kx^2\), where \(k\) is the spring constant and \(x\) is the displacement from the equilibrium position. Substituting the given values, we get \(PE = \frac{1}{2} \times 100 \times (0.2)^2 = 8\) J.

Correct Answer: C

Rationale: The femur is indeed the longest bone in the human body. It extends from the hip to the knee, providing crucial support for the body's weight and enabling various movements. The tibia and fibula are bones in the lower leg, while the humerus is located in the upper arm. Therefore, choices A, B, and D are incorrect in this context.

Correct Answer: D

Rationale: When light interacts with a perfectly smooth surface like a mirror, the dominant interaction is specular reflection. Specular reflection occurs when light rays are reflected off a smooth surface at the same angle as the incident angle, resulting in a clear and sharp reflection. Refraction, which involves the bending of light as it passes from one medium to another, is not the dominant interaction with a perfectly smooth surface. Diffraction, the bending of light waves around obstacles, is not the dominant interaction with smooth surfaces. Total internal reflection occurs when light is reflected back into a medium due to encountering a boundary at an angle greater than the critical angle, but it is not the dominant interaction on a perfectly smooth surface like a mirror.

Correct Answer: B

Rationale: Silicon is the correct answer. Silicon is widely used in semiconductors for electronic applications because of its unique properties that allow it to be manipulated to conduct or not conduct electricity effectively. Germanium is also used in semiconductors but to a lesser extent compared to silicon. Gallium and arsenic are not as commonly used in semiconductors like computer chips and solar panels, making them incorrect choices for this question.