Explain to the people of Westfield how the rust in their water formed.

It is almost time to explain to the people of Westfield how the rust in their water formed. What have you learned so far about how new substances form? List your ideas below.

The following section focuses on how rust forms.Read the information below and use it to answer the three selected-response questions and one constructed-response question that follow.At the beginning of summer, some paint was scratched off a student’s bicycle. The exposed metal where the bicycle was scratched had a shiny, silvery color. The student kept the bicycle outside all summer. By the end of summer, the exposed metal had changed to rust, which is dark orange in color.The student did some research to find out what happened to the metal and learned that the bicycle is made of steel, which contains mostly iron. The student conducted two investigations to learn more about the process that changed the steel into rust.Investigation 1: The student placed equal amounts of iron filings (small pieces of iron) into beakers X, Y, and Z. At the start of the investigation, all of the filings were gray. The student added nothing else to beaker X, water to beaker Y, and table salt (NaCl) and hydrogen peroxide (H2O2) to beaker Z. The student’s observations over a two-day period are shown in the table.Investigation 1Beaker Substance(s) Added Color of Filings on Day 1 Color of Filings on Day 2X none all gray all grayY a few drops of water all gray some gray and some dark orangeZ some table salt and a few drops of hydrogen peroxide some gray and some dark orange all dark orange Investigation 2: The student combined table salt and hydrogen peroxide in a beaker, added small pieces of steel, and placed a thermometer in the beaker. After one minute, the student measured the mass of the contents in the beaker. The student measured the contents in the beaker again at 10 minutes and discovered the mass had decreased slightly. The student’s observations are shown in the table.Investigation 2Beaker Contents at 1 Minute Beaker Contents at 10 Minutesa pale orange color a dark orange colorbubbling no longer bubbling25°C 40°C166.1 g 164.7 g

Rust is a chemical compound called iron oxide. It forms very slowly as iron reacts with oxygen and water.Select the reactants. IronIron oxideWaterOxygen

Read this excerpt from "The City Without Us" by Alan Weisman:Enemy number one is the salt that highway departments spread on the roadways each winter—ravenous stuff that keeps eating steel once it's done with the ice. Oil, antifreeze, and snowmelt dripping from cars wash salt into catch basins and crevices where maintenance crews must find and flush it. With no more people, there won't be salt. There will, however, be rust, and quite a bit of it, when no one is painting the bridges.Which sentence best states the main idea of this section of the chapter?A.Salt can be used as a metaphor for a monster that has a voracious appetite.B.Salt is the most damaging compound that people can use to fight snow and ice.C.Salt flushing and painting rusty bridges consume a large part of a city's budget.D.Salt and rust are corrosives that have damaging effects on a city's infrastructure.

Tasha knows that certain factors affect the rate at which an iron nail rusts. She conducted an experiment to determine which scenario would result in the greatest amount of rusting.Scenario 1: nail placed in a beaker and left exposed to airScenario 2: nail placed in a beaker and covered by tap waterScenario 3: nail placed in a beaker and covered by salt waterScenario 4: nail placed in a beaker and covered in alcoholAfter leaving the nails in the beakers for several days, Tasha observed that the greatest amount of rusting occurred inascenario 1 bscenario 2cscenario 3 dscenario 4