chemistry for health sciences quizlet

Correct Answer: C

Rationale: The correct answer is C: 19 p, 20 n, 19 e. K+ has an atomic number of 19, indicating 19 protons. Since it is a potassium ion with a +1 charge, it lost one electron, giving it 19 electrons instead of the usual 20. The number of neutrons is found by subtracting the atomic number from the mass number (39 for potassium) to get 20 neutrons. Option A is incorrect due to the incorrect number of electrons. Option B has the incorrect number of protons. Option D has the incorrect number of electrons.

Correct Answer: A

Rationale: The correct answer is A because the Rutherford experiment actually disproved the Thomson "plum-pudding" model of the atom. Rutherford's experiment involved firing alpha particles at a thin gold foil and observing their scattering patterns. The results showed that atoms have a small, dense, positively charged nucleus, which contradicted the Thomson model. Choice B is correct as the experiment was indeed useful in determining the nuclear charge on the atom. Choice C is incorrect because Millikan's oil-drop experiment determined the charge on the electron, not just that it was a simple multiple. Choice D is incorrect as the electric discharge tube did show that electrons have a negative charge.

Correct Answer: D

Rationale: The correct answer is D because gamma rays are not light but a form of electromagnetic radiation with high energy. Gamma rays have no charge and are produced from the nucleus. Choice A is correct as an alpha particle is heavier than an electron. Choice B is correct as an alpha particle has a 2+ charge. Choice C is correct as these are types of radioactive emissions.

Correct Answer: A

Rationale: To calculate normal human body temperature in �Z, we can use the formula: �Z = (�C + 100) / 2. Given that normal human body temperature in Celsius is 37�C, we substitute this into the formula: (37 + 100) / 2 = 137 / 2 = 68.5�Z. Therefore, the correct answer is A: 2968�Z, as it is the closest to 68.5�Z. Summary of other choices: B: 12.4�Z - This is too low, as human body temperature is higher. C: 111�Z - This is too high, as it exceeds the calculated value of 68.5�Z.

Correct Answer: C

Rationale: To find the density of liquid mercury in units of g/cm�, we need to convert the density from g/mL to g/cm�. The conversion factor is 1 mL = 1 cm�. Given the density of mercury as 6 g/mL, it is equivalent to 6 g/cm�. Therefore, the correct answer is 1.01 x 10� g/cm� (choice C). Choice A: 1.57 x 10� is too large for the density of liquid mercury. Choice B: 4.91 x 10� is incorrect as it does not match the calculated density. Choice D: 7.62 x 10� is significantly higher than the actual density of liquid mercury.