why does fluorine have a higher ionization energy than oxygen

HESI A2

Chemistry Hesi A2

1. Why does fluorine have a higher ionization energy than oxygen?

A. Fluorine has a smaller number of neutrons.
B. Fluorine has a larger number of neutrons.
C. Fluorine has a smaller nuclear charge.
D. Fluorine has a larger nuclear charge.

Correct answer: D

Rationale: Fluorine has a higher ionization energy than oxygen because fluorine has a larger nuclear charge. The greater number of protons in the nucleus of fluorine attracts its electrons more strongly, making it harder to remove an electron from a fluorine atom compared to an oxygen atom. Choice A is incorrect as the number of neutrons does not directly affect ionization energy. Choice B is also incorrect for the same reason. Choice C is incorrect because a smaller nuclear charge would result in lower ionization energy, not higher.

2. Subtract 20.7 - 13.4.

A. 7.1
B. 7.5
C. 7.3
D. 7.6

Correct answer: C

Rationale: The correct answer is 7.3. To subtract 13.4 from 20.7, you align the decimal points and subtract each place value: 0.7 - 0.4 = 0.3, and 2 - 1 = 1. Therefore, 20.7 - 13.4 = 7.3. Choices A, B, and D are incorrect because they do not provide the accurate result of this subtraction.

3. If two workers can finish building a play set in 18 hours, how long will it take 4 workers to build 3 play sets?

A. 27 hours
B. 36 hours
C. 24 hours
D. 54 hours

Correct answer: A

Rationale: If 2 workers can complete building one play set in 18 hours, it means one worker would take 36 hours to complete the same task. When the number of workers is doubled to 4, the time is halved, so 4 workers would take 18 hours to build one play set. To build 3 play sets, the total time needed would be 3 times the time for one play set, which equals 54 hours. Therefore, 4 workers can build 3 play sets in 27 hours, making choice A the correct answer. Choices B, C, and D are incorrect because they do not account for the correct relationship between the number of workers and the time required to complete the task.

4. A woman received a bottle of perfume as a present. The bottle contains 1/2 oz of perfume. How many milliliters is this?

A. 15 mL
B. 20 mL
C. 10 mL
D. 50 mL

Correct answer: A

Rationale: 1/2 oz of perfume is equal to approximately 15 mL. To convert ounces to milliliters, we need to know that 1 oz is approximately 30 mL. Therefore, half an ounce, which is 1/2 oz, would be half of 30 mL, which equals 15 mL. Choice B, 20 mL, is incorrect as it does not correspond to the conversion factor of 1 oz to 30 mL. Choice C, 10 mL, is incorrect as it is half of the actual value. Choice D, 50 mL, is incorrect as it is the value of 1 oz rather than half an ounce.

5. Which word is not spelled correctly in the context of the sentence? You will need counsel if you are accused of a serious crime.

A. counsel
B. accused
C. serious
D. crime

Correct answer: A

Rationale: The correct spelling of the word in the sentence should be 'counsel' instead of 'council.' 'Counsel' refers to legal advice or a person or group of people giving advice or guidance. The other choices ('accused,' 'serious,' 'crime') are spelled correctly and are relevant in the context of the sentence.