Which of the following is a weak acid commonly found in citrus fruits?

Correct Answer: C

Rationale: Citric acid is a weak acid commonly found in citrus fruits like lemons, oranges, and limes. It is responsible for the sour taste in these fruits. Sulfuric acid (option A), hydrochloric acid (option B), and nitric acid (option D) are all strong acids that are typically used in laboratory settings and industrial processes, not naturally found in citrus fruits. Therefore, the correct answer is option C.

Correct Answer: A

Rationale: The unit of measurement for force in the International System of Units (SI) is the Newton (N). One Newton is defined as the force required to accelerate a mass of one kilogram at a rate of one meter per second squared. Therefore, the correct answer is Newton (N). The other choices are incorrect because: B) Kilogram (kg) is a unit of mass, not force; C) Joule (J) is a unit of energy; D) Meter per second squared (m/s²) is a unit of acceleration, not force.

Correct Answer: C

Rationale: The correct answer is Newton's Third Law of Motion. This law states that for every action, there is an equal and opposite reaction. It means that when one object exerts a force on a second object, the second object exerts an equal force in the opposite direction back on the first object. This fundamental law describes the relationship between the forces acting on two interacting objects. Newton's First Law (Choice A) is known as the law of inertia and states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an external force. Newton's Second Law (Choice B) relates the force acting on an object to its mass and acceleration. The Law of Universal Gravitation (Choice D) describes the force of gravity between two objects with mass and the distance between them.

Correct Answer: C

Rationale: Proteins are macromolecules made up of long chains of amino acids. Amino acids are the building blocks of proteins and are linked together through peptide bonds to form polypeptide chains, which then fold into specific three-dimensional structures to carry out various functions in the body. Sugars (choice A) are the building blocks of carbohydrates, fatty acids (choice B) are the building blocks of lipids, and nucleotides (choice D) are the building blocks of nucleic acids like DNA and RNA. Therefore, the correct answer is amino acids (choice C), as they are specifically responsible for protein synthesis.

Correct Answer: C

Rationale: The correct answer is C: Weight is greater than mass. Mass is a measure of the amount of matter in an object, while weight is the force of gravity acting on that object. On Earth's surface, weight is greater than mass because gravity pulls objects towards the center of the Earth, resulting in a force that we perceive as weight. Choice A is incorrect because mass and weight are not equal; weight is a force, while mass is a measure of the amount of matter. Choice B is incorrect because mass is not greater than weight; weight is the force exerted due to gravity. Choice D is incorrect as mass and weight are related; weight is dependent on mass and the gravitational force acting on the object.