Nokea
What volume of silver metal will weigh exactly 2500.0 g? The density of silver is 10.5 g/cm³.
- A. 26250 cm³
- B. 238.1 cm³
- C. 0.0042 cm³
- D. None of the above
Correct Answer: B
Rationale: To determine the volume of silver, we use the formula: Volume = Mass / Density. Substituting the given values, Volume = 2500.0 g / 10.5 g/cm³ = 238.1 cm³. Therefore, the correct answer is 238.1 cm³, which represents the volume of silver metal weighing precisely 2500.0 g at a density of 10.5 g/cm³.
You may also like to solve these questions
Will solids always sink in liquids?
- A. True, a solid is hard, and liquids are not.
- B. True, solids are heavier than liquids.
- C. False, solids have a smooth surface so they will float.
- D. False, it depends on the density of the solid and liquid.
Correct Answer: D
Rationale: Solids will not always sink in liquids. Whether a solid sinks or floats in a liquid depends on the relative densities of the solid and the liquid. If the density of the solid is greater than that of the liquid, it will sink. If the density of the solid is less than that of the liquid, it will float. Therefore, it is incorrect to state that solids will always sink in liquids without considering their respective densities. The weight or hardness of the solid and the smoothness of its surface do not determine whether it will sink or float in a liquid. The critical factor is the density relationship between the solid and the liquid.
What type of reaction is represented by the equation KCl → K + Cl₂?
- A. Synthesis
- B. Decomposition
- C. Single replacement
- D. Double replacement
Correct Answer: B
Rationale: The reaction KCl → K + Cl2 is an example of a decomposition reaction. In a decomposition reaction, a compound breaks down into its constituent elements or simpler compounds. In this case, potassium chloride (KCl) decomposes into potassium (K) and chlorine gas (Cl2). Therefore, the correct answer is B, Decomposition.
What is the atomic number?
- A. Number of neutrons
- B. Number of protons
- C. Number of electrons
- D. Number of isotopes
Correct Answer: B
Rationale: The atomic number is the number of protons in an atom's nucleus. It uniquely identifies an element and determines its chemical properties. The number of neutrons and electrons can vary in an atom, but the number of protons remains constant for a specific element. Therefore, the correct answer is the 'Number of protons' (Choice B).
In an experiment, a student tests three unknown fluids with the following measurements: Fluid A: m=2060g, V=2000mL, Fluid B: m=672g, V=850mL, and Fluid C: m=990g, V=1100mL. Arrange the liquids in the correct order of how they would separate in a beaker from bottom to top.
- A. A, B, C
- B. B, C, A
- C. C, A, B
- D. B, A, C
Correct Answer: B
Rationale: To determine the order in which the liquids will separate in a beaker, we must consider their densities, calculated using the formula Density = Mass (m) / Volume (V). The liquid with the higher density will settle at the bottom, while the liquid with the lower density will rise to the top. For the given fluids, Fluid A has a density of 1.03 g/mL (2060 g / 2000 mL), Fluid B has a density of approximately 0.79 g/mL (672 g / 850 mL), and Fluid C has a density of approximately 0.90 g/mL (990 g / 1100 mL). Based on these calculations, the correct order of the fluids from bottom to top, according to increasing density, is Fluid B, Fluid C, and Fluid A.
Which element has 13 protons, 13 electrons, and 14 neutrons?
- A. Fe
- B. Zr
- C. Al
- D. Not enough information
Correct Answer: C
Rationale: The element with 13 protons is Aluminum (Al), as the atomic number of an element is determined by the number of protons. The total number of protons and neutrons in an element's nucleus is known as the mass number. Given that the mystery element has 13 protons and 14 neutrons, it matches the characteristics of Aluminum, making it the correct answer.