HESI A2
Chemistry HESI A2 Quizlet
1. What number represents the number of protons an element has?
- A. Atomic mass
- B. Mass number
- C. Atomic number
- D. Neutron number
Correct answer: C
Rationale: The correct answer is C, atomic number. The atomic number corresponds to the number of protons in an element. This number is unique to each element and determines its placement on the periodic table. It is equal to the number of protons found in the nucleus of an atom of that element. Choice A, atomic mass, represents the average mass of an element's isotopes. Choice B, mass number, is the sum of protons and neutrons in an atom. Choice D, neutron number, specifically refers to the count of neutrons in an atom and not protons.
2. What percentage of her income is left after Mary spent 15%?
- A. 12%
- B. 85%
- C. 75%
- D. 95%
Correct answer: B
Rationale: To determine the percentage of income remaining after spending 15%, subtract the percentage spent from 100% (100% - 15% = 85%). Therefore, Mary has 85% of her income left, which aligns with answer choice B. Choice A (12%) is incorrect because it represents the remaining amount after spending 88% of her income. Choice C (75%) is incorrect as it does not account for the 15% already spent. Choice D (95%) is incorrect as it does not consider the amount spent by Mary.
3. What is 50% of 120?
- A. 50
- B. 50
- C. 70
- D. 60
Correct answer: D
Rationale: The correct answer is D, 60. To find 50% of 120, you multiply 0.5 by 120: 0.5 x 120 = 60. Choice A and B are incorrect as they are duplicates. Choice C, 70, is incorrect because it is not the result of calculating 50% of 120.
4. Change the decimal to a percent: 0.64 =
- A. 0.64%
- B. 6.4%
- C. 64%
- D. 0.064%
Correct answer: C
Rationale: To convert a decimal to a percent, multiply by 100. In this case, 0.64 × 100 = 64%. Therefore, the correct answer is C. Choice A (0.64%) is incorrect as it represents the original decimal value in percentage form. Choice B (6.4%) is incorrect as it incorrectly multiplies the decimal value by 10 instead of 100. Choice D (0.064%) is incorrect as it represents the decimal value as a fraction of 1000 instead of 100.
5. As cattle graze, cattle egrets consume the insects they stir up. This is an example of ___________.
- A. Mutualism
- B. Parasitism
- C. Commensalism
- D. Competition
Correct answer: C
Rationale: Commensalism is a relationship between two species in which one benefits without affecting the other species. In this scenario, the cattle egrets benefit from the insects stirred up by cattle while the cattle are not significantly impacted by the presence of the egrets. The egrets obtain food easily, and the cattle are neither harmed nor helped by the egrets' presence, making it an example of commensalism. Mutualism involves both species benefiting, parasitism involves one species benefiting at the expense of the other, and competition involves both species being negatively affected by their interactions, none of which apply to the relationship between cattle and cattle egrets in this context.
Similar Questions
Access More Features
HESI A2 Basic
$49/ 30 days
- 3,000 Questions with answers
- 30 days access
HESI A2 Premium
$99/ 90 days
- Actual HESI A2 Questions
- 3,000 questions with answers
- 90 days access