Nursing Elites

1. What is the charge of a beta particle?

• A. -1
• B. +1
• C. +2
• D. No charge

Correct answer: A

Rationale: A beta particle has a charge of -1. Beta particles are high-energy, high-speed electrons emitted during radioactive decay processes. Since electrons carry a charge of -1, beta particles also carry a charge of -1. This negative charge indicates that beta particles are negatively charged. Option B is incorrect as it suggests a positive charge, which is not the case for beta particles. Option C is incorrect as it indicates a higher positive charge, which is not true for beta particles. Option D is incorrect as beta particles do have a charge, which is negative.

2. Which of these elements has the greatest atomic mass?

• A. Au
• B. Ba
• C. I
• D. W

Correct answer: D

Rationale: Among the elements listed, Tungsten (W) has the greatest atomic mass. The atomic mass of Tungsten is approximately 183.84 atomic mass units (amu), while the atomic masses of the other elements listed are as follows: Gold (Au) is around 196.97 amu, Barium (Ba) is approximately 137.33 amu, and Iodine (I) is about 126.90 amu. Therefore, Tungsten (W) has the greatest atomic mass out of the given elements. Gold (Au) has a higher atomic mass than Barium (Ba) and Iodine (I), making choices A, B, and C incorrect.

3. What defines a balanced chemical equation?

• A. An equation where the number of atoms of each element is the same on both sides
• B. An equation where there are more products than reactants
• C. An equation where the number of molecules is balanced
• D. An equation with equal masses on both sides

Correct answer: A

Rationale: A balanced chemical equation is one in which the number of atoms of each element is the same on both sides. This balance ensures the law of conservation of mass is upheld, where the total mass of the reactants equals the total mass of the products. Options B, C, and D are incorrect. Option B is incorrect as a balanced equation has an equal number of products and reactants. Option C is incorrect as balancing refers to the number of atoms, not molecules. Option D is incorrect as balancing is based on the number of atoms, not masses. Therefore, option A is the correct choice as it accurately describes a balanced chemical equation.

4. How many neutrons are in an atom of helium-4?

• A. 2
• B. 3
• C. 4
• D. 6

Correct answer: A

Rationale: The atomic number of helium is 2, indicating it has 2 protons. Helium-4, the most common isotope of helium, has 2 neutrons in addition to its 2 protons. Therefore, the correct answer is 2 neutrons in an atom of helium-4. Choice B, C, and D are incorrect as they do not match the correct composition of helium-4, which consists of 2 protons and 2 neutrons.

5. What is the pH of acids?

• A. 7.5
• B. < 7
• C. > 7
• D. 7

Correct answer: B

Rationale: The correct answer is B: < 7. Acids have a pH lower than 7, indicating higher acidity. A pH below 7 signifies an acidic solution, with lower values indicating stronger acids. Choice A (7.5) is incorrect as it is greater than 7, which is alkaline. Choice C (> 7) is incorrect as values greater than 7 represent alkaline/basic solutions. Choice D (7) is incorrect because a pH of 7 is neutral, not acidic.

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