Question

1. which of the following best describes the first law of thermodynamics? (a) energy always changes from a more useful, more concentrated form to a less useful, less concentrated form. (b) in a closed system of constant mass, the energy involved in any physical or chemical change is neither created nor destroyed, but merely changed from one form to another. (c) heat always flows from a hot body to a cold body. (d) entropy of a system increases as the state of disorganization in the system increases. (e) in a reversible process, the entropy of the system is constant, whereas in an irreversible process, the entropy of the system increases. 2. which of the following best explains why decomposers in soils and water are important to ecosystems? (a) they remove heavy metals. (b) they store carbon dioxide. (c) they recycle nutrients. (d) they neutralize acid deposition. (e) they produce more oxygen than they consume. 3. which of the following pathways indicate how nitrogen is added to the largest nitrogen reservoir? (a) nitrifying bacteria and lightning (b) decomposing plant and animal material (c) denitrifying bacteria and volcanic activity (d) nitrates taken up by plant roots this rate of reaction can be measured in the dark by determining the amount of oxygen gas consumed in a period of time

Explanation:

1. The first - law of thermodynamics states that in a closed system of constant mass, energy is conserved and is neither created nor destroyed, just transformed from one form to another. Option (B) correctly describes this. Option (A) is related to the second - law of thermodynamics about energy degradation. Option (C) is a statement about heat transfer. Options (D) and (E) are about entropy concepts.
2. Decomposers in soils and water are important to ecosystems because they recycle nutrients. They break down dead organisms and waste materials, releasing nutrients back into the environment for plants and other organisms to use. They do not primarily remove heavy metals, store carbon dioxide, neutralize acid deposition, or produce more oxygen than they consume.
3. The largest nitrogen reservoir is the atmosphere. Denitrifying bacteria convert nitrates into nitrogen gas and release it into the atmosphere, and volcanic activity can also release nitrogen - containing gases into the atmosphere. Nitrifying bacteria convert ammonia to nitrites and nitrates in the soil, and lightning fixes nitrogen but not as much as denitrifying bacteria in terms of adding to the atmospheric reservoir. Decomposing plant and animal material and plant roots taking up nitrates do not add nitrogen to the atmospheric reservoir.

Answer:

1. B. In a closed system of constant mass, the energy involved in any physical or chemical change is neither created nor destroyed, but merely changed from one form to another.
2. C. They recycle nutrients.
3. C. Denitrifying bacteria and volcanic activity