Nokea
Chemical reactions in living systems proceed along catabolic pathways, leading to an increase in which of the following?
- A. Entropy
- B. Enthalpy
- C. Glucose
- D. Glycogen
Correct Answer: A
Rationale: In catabolic pathways, complex molecules are broken down into simpler ones, releasing energy. This process increases entropy, which is a measure of disorder or randomness in a system. As molecules are broken down, they become more disordered, causing an increase in entropy. Therefore, the correct answer is 'Entropy.' Enthalpy refers to the total heat content of a system, glucose and glycogen are specific molecules and not directly related to the increase in disorder during catabolic reactions.
You may also like to solve these questions
What is 119 K in degrees Celsius?
- A. 32C
- B. -154C
- C. 154C
- D. -32C
Correct Answer: B
Rationale: To convert from Kelvin to Celsius, you subtract 273.15 from the temperature in Kelvin. Therefore, 119 K - 273.15 = -154C. Hence, 119 K is equivalent to -154C. The correct answer is -154C, as it results from the conversion formula from Kelvin to Celsius.
What can be predicted by using the periodic table?
- A. The properties of each element
- B. The charges of polyatomic ions
- C. The number of isotopes for each element
- D. The potential for discovering new elements
Correct Answer: A
Rationale: The periodic table organizes elements based on their properties, such as atomic number, electron configuration, and chemical behavior. By examining an element's position on the periodic table, one can predict its properties, including its physical and chemical characteristics, reactivity, and other behaviors. This predictive ability is one of the fundamental strengths of the periodic table in understanding and working with elements. Therefore, the correct answer is A, as the periodic table allows for the prediction of the properties of each element based on its location and characteristics within the table.
Which type of bond involves atoms gaining or losing electrons?
- A. Ionic
- B. Covalent
- C. Both
- D. Neither
Correct Answer: A
Rationale: Ionic bonds involve the transfer of electrons between atoms, leading to one atom gaining electrons (becoming negatively charged) while the other loses electrons (becoming positively charged). This results in the formation of ions that are held together by electrostatic forces, creating an ionic bond. In a covalent bond, atoms share electrons rather than gaining or losing them, making option A, 'Ionic,' the correct answer to this question. Therefore, the correct answer is 'Ionic,' as it specifically involves gaining or losing electrons to form a bond.
What is the general reaction for neutralizing acids and bases?
- A. Acid + base → water + salt
- B. Base + water → acid + salt
- C. Salt + water → acid + base
- D. Acid + base → water + salt
Correct Answer: D
Rationale: The correct general reaction for neutralizing acids and bases is when an acid reacts with a base, it forms water and a salt. This reaction is commonly known as a neutralization reaction. The hydrogen ions from the acid combine with the hydroxide ions from the base to form water, while the anion from the acid combines with the cation from the base to form a salt.
Which of the following states of matter exhibits the most molecular motion?
- A. Solid
- B. Liquid
- C. Gas
- D. None of the above
Correct Answer: C
Rationale: The correct answer is 'C: Gas'. Gas exhibits the most molecular motion compared to solid and liquid states. In a gas state, molecules possess high kinetic energy, are spaced far apart, and move freely in all directions. This results in increased molecular motion compared to the more structured and restricted motion observed in solids and liquids. In solids, molecules are tightly packed and have minimal movement, while in liquids, although the molecules are more mobile than in solids, they are still more constrained compared to gases. Therefore, gas stands out as the state of matter with the highest molecular motion due to the high energy and freedom of movement of its molecules.