ATI RN
chemistry for health sciences Questions
Question 1 of 9
The chemist credited for inventing a set of symbols for writing elements and a system for writing the formulas of compounds (and for discovering selenium, silicon, and thorium) is
Correct Answer: D
Rationale: The correct answer is D: Berzelius. Berzelius is credited with inventing symbols for elements and a system for writing compound formulas. He also discovered selenium, silicon, and thorium. Berzelius made significant contributions to the field of chemistry. A: Boyle is known for Boyle's Law related to gases, not for inventing chemical symbols or discovering elements. B: Lavoisier is known as the father of modern chemistry but did not invent chemical symbols or discover these elements. C: Priestly is known for discovering oxygen, but not for the specific contributions mentioned in the question.
Question 2 of 9
Express the volume 781.2CM3 in liters.
Correct Answer: D
Rationale: To convert cm3 to liters, divide by 1000 as 1 liter = 1000 cm3. Therefore, 781.2 cm3 ÷ 1000 = 0.7812 L. Correct answer is D: 0.7812 L. Other choices are incorrect as they do not reflect the correct conversion from cm3 to liters.
Question 3 of 9
The degree of agreement among several measurements of the same quantity is called . It reflects the reproducibility of a given type of measurement.
Correct Answer: C
Rationale: The correct answer is C: precision. Precision refers to the degree of agreement among repeated measurements of the same quantity. It reflects how close the measurements are to each other, indicating reproducibility. Accuracy (choice A) is about how close a measurement is to the true value, not the agreement among multiple measurements. Error (choice B) is a deviation from the true value and not specifically related to the agreement among measurements. Significance (choice D) is about the importance or relevance of a result, not the consistency of measurements. Therefore, precision is the most appropriate term in this context.
Question 4 of 9
Considering the plot of total mass (y-axis) versus volume (x-axis), which of the following is true?
Correct Answer: A
Rationale: The correct answer is A. The plot of total mass versus volume should be rather linear because the slope measures the density of a liquid. This is because density is defined as mass divided by volume (density = mass/volume). Therefore, when mass is plotted against volume, the slope of the line represents the density of the liquid. A linear relationship between mass and volume indicates that the density remains constant. Summary of other choices: B: The plot being curved upward due to slope measuring density is incorrect. C: The plot being curved upward due to mass being higher in successive trials is incorrect. D: The plot being linear because the mass of the beaker stays constant is incorrect.
Question 5 of 9
Convert 4338 mL to qt. (1 L = 06 qt)
Correct Answer: B
Rationale: To convert 4338 mL to qt, first convert mL to L by dividing by 1000 (4338 mL / 1000 = 4.338 L). Then, convert L to qt using the conversion factor 1 L = 0.946 qt. So, 4.338 L * 0.946 qt/L = 4.092 qt (Answer B). Choice A (4598 qt) is incorrect as it does not follow the correct conversion process. Choice C (4.092 10 3 qt) is incorrect due to incorrect formatting and notation. Choice D (4092 qt) is incorrect as it uses the wrong conversion factor.
Question 6 of 9
Manganese makes up 3 10–4 percent by mass of the elements found in a normal healthy body. How many grams of manganese would be found in the body of a person weighing 206 lb? (205 lb = 1 kg)
Correct Answer: A
Rationale: To calculate the grams of manganese in a 206 lb body, first convert pounds to kg (206 lb = 93.44 kg). Then, use the given percentage (3 10–4%) to find the amount of manganese in the body (93.44 kg * 0.0003 = 0.028032 g). Since 205 lb = 1 kg, the correct answer is 0.028032 g or approximately 0.59 g (rounding). Summary of other choices: B: Incorrect, this does not consider the correct conversion and percentage calculation. C: Incorrect, this is a much larger value and does not align with the given percentage. D: Incorrect, this is also a much larger value and does not align with the given percentage.
Question 7 of 9
Order the four metric prefixes from smallest to largest.
Correct Answer: A
Rationale: The correct order is A: nano- < milli- < centi- < kilo-. The rationale is as follows: 1. Start from the smallest prefix, which is nano- representing 10^-9. 2. Moving up, milli- comes next representing 10^-3, which is larger than nano-. 3. Following milli- is centi- representing 10^-2, larger than milli-. 4. Lastly, kilo- is the largest prefix representing 10^3, making it the largest of the four options. Therefore, the correct order is nano- < milli- < centi- < kilo-. The other choices are incorrect because they do not follow the correct increasing order of magnitude for the metric prefixes.
Question 8 of 9
409 Kelvin equals
Correct Answer: D
Rationale: To convert Kelvin to Celsius, subtract 273. So, 409K - 273 = 136°C. Choice D is correct. Choice A (136°F) is incorrect because it's a Fahrenheit conversion. Choice B (273°F) is incorrect, as it doesn't convert Kelvin to Fahrenheit. Choice C (682°F) is incorrect, as it's double the incorrect Fahrenheit conversion.
Question 9 of 9
The density of oleic acid is 895 g / mL. What is the thickness of the monolayer (the length of an oleic acid molecule)?
Correct Answer: B
Rationale: The correct answer is B. To calculate the thickness of the monolayer, we need to use the formula thickness = density / (Avogadro's number * molecular weight). Given the density of oleic acid (895 g/mL), we can substitute this value along with the molecular weight of oleic acid into the formula. By dividing the density by the product of Avogadro's number and the molecular weight, we obtain the thickness in cm. The other choices are incorrect because they do not consider the given density and relevant constants in the calculation. Choice A, C, and D do not follow the correct formula for determining the thickness of the monolayer.