Question

6 multiple choice 1 point according to table 1, as the nacl concentration decreases, what generally happens to the boiling point of the liquid? decreases stays the same increases then decreases increases 7 multiple choice 1 point based on the results of experiment 1, if a student were to take a 300 - mg sample of steel wool and place it in 400 ml of distilled water with 30 ml of sodium chlorite bleach, what is the most likely amount of rust that would be created after 2 days? 0.75 mg 25 mg 1.0 mg 0.5 mg 8 multiple choice 1 point an electric power company is planning to provide electricity to a small island in the middle of a clean lake. although the wire being used has a plastic coating, the company is concerned that if any small part of the coating comes off, the wire will rust. based on the information presented, is this a valid concern? yes, because in experiment 1, there will be rust caused by exposure to water. no, because the amount of wiring used would be insignificant. no, because in experiment 2, having an electric current run through a wire minimizes rust. yes, because in experiment 1, exposure to the water will only increase rust over time.

Explanation:

Step1: Recall colligative properties

The boiling - point elevation is a colligative property. The presence of a solute (like NaCl) in a solvent increases the boiling point. As the concentration of the solute (NaCl) decreases, the effect on the boiling point also decreases. So, the boiling point of the liquid decreases.

Step2: Analyze rust - formation in Experiment 1

Since no data about Experiment 1 results is given, we assume based on general knowledge of rust - formation. Rust (iron oxide) forms when iron (in steel wool) reacts with oxygen and water. Without specific data from Experiment 1, we cannot accurately calculate the amount of rust. But if we assume a proportional relationship (if such was established in Experiment 1), we still lack the necessary data. However, if we consider typical rust - formation rates in similar set - ups, we know that rust formation is a slow process. Among the options, 0.25 mg seems a reasonable estimate for a 2 - day period for a 300 - mg steel wool sample in the given solution.

Step3: Evaluate rust - concern for wire

Rust forms when iron is exposed to oxygen and water. In a clean lake, if the plastic coating on the wire comes off, the iron wire will be exposed to water and oxygen (dissolved in water), and rust will form. Based on general knowledge of rust - formation and the information that water is present, it is a valid concern.

Answer:

1. decreases
2. 0.25 mg
3. Yes, because in Experiment 1, there will be rust caused by exposure to water.