What is a characteristic property of acids?

Correct Answer: B

Rationale: The correct characteristic property of acids is a sour taste. Acids release hydrogen ions when dissolved in water, giving them a sour taste. Bitter taste is a property associated with bases, not acids. Slippery feel is a characteristic property of bases, due to their soap-like nature. Sweet taste does not accurately describe the characteristic property of acids, as they are known for their sour taste.

Correct Answer: D

Rationale: Bases are substances that can accept protons or donate hydroxide ions in a chemical reaction. One common property of bases is that they turn red litmus paper blue. This is a classic test to distinguish between acids (which turn blue litmus paper red) and bases. Conductivity in aqueous solutions (Option A) is a property of both acids and bases, but not unique to bases alone. Sour taste (Option B) is a property commonly associated with acids, not bases. Reactivity with metals to produce hydrogen gas (Option C) is a property of acids, particularly strong acids, but not bases.

Correct Answer: B

Rationale: An unsaturated solution is the term used for a solution that has a lower concentration of solute compared to another solution. In an unsaturated solution, more solute could still be dissolved. The other options are incorrect. A saturated solution (A) contains the maximum amount of solute that can be dissolved and is in equilibrium with undissolved solute. A dilute solution (C) has a low concentration of solute, but it does not imply a comparison to another solution. A concentrated solution (D) has a high concentration of solute compared to the solvent, which is opposite to what is described in the question.

Correct Answer: C

Rationale: Friction is a force that opposes motion. When two surfaces are in contact, friction acts in the opposite direction to the motion or the potential motion between the two surfaces. It resists the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Friction hinders or prevents motion rather than promoting it. Choices A, B, and D are incorrect as they suggest that friction increases, accelerates, or creates motion, which is inaccurate. The correct definition of friction is that it opposes motion, making choice C the most appropriate option.

Correct Answer: A

Rationale: Inertia is the term that describes the resistance of an object to changes in its motion. This property is explained by Newton's First Law of Motion, which states that objects tend to maintain their state of motion unless acted upon by an external force. Inertia is closely related to mass, where objects with more mass exhibit more resistance to changes in motion. Momentum (B) is the product of an object's mass and velocity, gravity (C) is the force of attraction between objects, and kinetic energy (D) is the energy associated with an object's motion. Therefore, the correct answer is A because inertia specifically addresses the resistance of an object to changes in its motion.