Jamie completes the following steps in an experiment to investigate how temperature affects how fast something will rust in water. He places a nail in a bowl of water in the sun and a nail in a bowl of water in the shade. He also leaves an iron nail out of the water in a dry bag out of the sun. Why would Jamie leave one out of the water and out of the sun?  Jamie also wants to test if the water affects how fast the iron nail will rust. Jamie notices that the size of the nail is different, so he does not want to use it later. Jamie doing all these steps to create a control group to compare his results to. Jamie puts the nail in a cooler place to see if it will rust as fast as the other items.

7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation. 8. when a 2.5 mol of sugar (c12h22o11) are added to a certain amount of water the boiling point is raised by 1 celsius degree. if 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? show all calculations leading to your answer or use 3 – 4 sentences to explain your answer. 9. if 5.40 kcal of heat is added to 1.00 kg of water at 100⁰c, how much steam at 100⁰c is produced? show all calculations leading to an answer. 10. the freezing of water at 0⁰c can be represented as follows: h2o (l) ↔ h2o(s) the density of liquid water is 1.00 g/cm3. the density of ice is 0.92 g/cm3. in 3 – 4 sentences explain why applying pressure causes ice to melt.