Water is considered a universal solvent due to its ____.

Correct Answer: B

Rationale: The correct answer is B: Adhesion. Water's polarity allows it to dissolve many substances due to its ability to adhere to and interact with other molecules, making it an effective solvent. Cohesion refers to water molecules sticking together, molarity is a measure of concentration, and dilution refers to the process of reducing the concentration of a solute in a solution, none of which directly relate to water's role as a universal solvent.

Correct Answer: D

Rationale: The independent variable is the factor that is manipulated by the researcher to observe its effects on the dependent variable. In this experiment, the researcher is likely changing the type of dog food, and this manipulation is what impacts the outcome being measured. Therefore, 'Dog food type' is the independent variable. Choices A, B, and C do not represent the variable being intentionally changed by the researcher, making them dependent variables or other factors not directly controlled or manipulated in this experiment.

Correct Answer: C

Rationale: The correct answer is C because DNA is typically read from the 5' end to the 3' end, not from 3' to 5'. Choices A, B, and D are all true statements about DNA. DNA contains the nucleotides A, T, C, G and is read in a 5' to 3' direction. DNA also contains genetic information and is tightly coiled with proteins to form chromosomes. Additionally, DNA is a double-stranded molecule connected by hydrogen bonds.

Correct Answer: B

Rationale: The correct answer is B (6 protons). The electron configuration provided corresponds to the element carbon, which has 6 protons. The mass number does not affect the number of protons in an atom, so despite the mass number of 14, the atom still contains 6 protons. Choice A (14) is incorrect because the mass number does not determine the number of protons. Choices C (8) and D (12) are incorrect as they do not match the number of protons in a carbon atom.

Correct Answer: B

Rationale: A negative ion of sulfur would have 16 protons and 17 electrons since it gains one electron. The number of neutrons in an ion does not change, so the neutrons would remain at 16. Therefore, the correct answer is 16 neutrons and 17 electrons, which corresponds to choice B. Choice A is incorrect as it does not account for the extra electron gained by the negative ion. Choices C and D are incorrect because they propose a change in the number of neutrons, which is not affected by the ionization process.