Question

Lab report for How does adding salt affect the freezing point of water

Answer 1

As a higher percentage of salt is added into the water, the freezing point drops - you can kind of think of the ocean as an example - you'll find more ice the closer you get to the poles of the Earth because the temperature drops and becomes capable of freezing ocean brine.

Answer 2

http://www.planetseed.com/posted_faq/50342

When salt (NaCl) dissolves in water, its sodium (Na+) and chlorine (Cl-) ions leave the salt crystals and mix separately among the water molecules. These ions affect the water molecules and their freezing and boiling temperatures in different ways:

1. Lower freezing point
Water molecules form crystals when freezing. Na+ and Cl- ions from the salt get in the way of the water molecules, making it harder for them to become re-arranged into crystals. This means that salt water remains in a liquid state for longer as the temperature reduces.

Answer 3

http://www.reference.com/motif/science/how-does-salt-affect-the-boiling-point-of-water

Adding salt to water increases its boiling point. However, adding any solute to water - sand, sugar, a child's toy, or your utensil - will also increase its boiling point. Any non-volatile substance as a solute will raise the boiling pressure of the solvent and also decrease the freezing point of the solvent. This is the purpose to antifreeze being added to water in an automobile's radiator. The antifreeze increases the boiling point in the summer, keeping the radiator cooler than just the water, and lowers the freezing point in the winter, keeping the radiator from cracking due to ice forming inside, because ice takes up more space than the liquid water. This phenomenon of a solute affecting a solvent's boiling or freezing point is also illustrated by the salt used to melt ice in the winter. Because the salt lowers the freezing point of the ice, the ice melts - the temperature ceases to be cold enough to keep the ice frozen with the addition of a solute.The properties of solutes and their effects on solvents are termed colligative properties. The extent to which solutes affect solvents is dependent on the amount of solute relative to the solvent. Colligative properties depend on the relative concentration of a solution, so adding a non-volatile solute to a solvent will increase its boiling point or decrease its freezing point in a manner directly related to the amount of solute added. Therefore, the more salt that is added to liquid water in a pan, the longer it will take to boil. The more salt added to ice, the faster it will melt. The greater the antifreeze in a radiator, the more effective the radiator will be, because the water now boils more slowly and also freezes more slowly than if only a small amount of antifreeze was added. For more information, please see the below links. More reference links: www.sciencebase.com www.newton.dep.anl.gov