Nursing Elites

1. Which gas is produced when an acid reacts with a carbonate?

• A. Carbon dioxide
• B. Oxygen
• C. Hydrogen
• D. Nitrogen

Correct answer: A

Rationale: When an acid reacts with a carbonate, the chemical reaction typically yields carbon dioxide gas. Carbon dioxide is formed due to the chemical reaction between the acid and the carbonate, releasing this gas as a product. Therefore, the correct answer is 'Carbon dioxide.' Choices B, C, and D are incorrect as oxygen, hydrogen, and nitrogen are not the gases produced in this specific acid-carbonate reaction.

2. What is the mass number of an atom with 6 protons, 6 neutrons, and 6 electrons?

• A. 12
• B. 18
• C. 6
• D. 8

Correct answer: A

Rationale: The mass number of an atom is the sum of protons and neutrons. In this case, the atom has 6 protons and 6 neutrons, thus the mass number is 6 + 6 = 12. Therefore, choice A (12) is the correct answer. Choices B (18), C (6), and D (8) are incorrect because the mass number is determined by the sum of protons and neutrons, not the number of electrons or a different combination of particles.

3. What type of chemical reaction is represented by AB → A + B?

• A. Synthesis
• B. Decomposition
• C. Single replacement
• D. Double replacement

Correct answer: B

Rationale: The chemical equation AB → A + B represents a decomposition reaction. In a decomposition reaction, a single compound breaks down into two or more simpler substances. In this specific reaction, compound AB is decomposed into its elements, A and B, making it a decomposition reaction. Choice A, Synthesis, involves the combination of two or more substances to form a more complex product, which is not the case here. Choices C and D, Single replacement and Double replacement, involve the exchange of ions between compounds or elements, which is not happening in the given reaction.

4. Which of the following can act as a catalyst in a chemical reaction?

• A. Enzyme
• B. Light
• C. Water
• D. Metal

Correct answer: A

Rationale: Enzymes are biological catalysts that speed up chemical reactions without being consumed. They lower the activation energy required for the reaction to occur, facilitating and accelerating the process. Choice B, Light, is not a catalyst but can sometimes trigger reactions by providing energy. Choice C, Water, and choice D, Metal, are not catalysts but can participate in reactions as reactants.

5. What is 119 K in degrees Celsius?

• A. 32°C
• B. -154°C
• C. 154°C
• D. 0°C

Correct answer: B

Rationale: To convert Kelvin (K) to Celsius (°C), you subtract 273.15 from the Kelvin value. Therefore, 119 K - 273.15 = -154.15°C. The negative sign indicates that the temperature is below freezing. When rounded to the nearest whole number, -154.15°C is approximately -154°C. Choice A and Choice C are incorrect as they do not reflect the correct conversion from Kelvin to Celsius. Choice D is incorrect as it corresponds to the freezing point of water in Celsius, not the conversion of 119 K.

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