Chemistry projects are a great way to learn use science as a tool.
Science projects can be a win in more ways than one. They're an excellent way to learn the scientific method. By conducting your own experiments, you'll learn to develop hypotheses, then test them, then draw conclusions about the validity of your hypotheses. Before you begin work on your winning chemistry projects, learn laboratory safety protocols.
Fog
Dry ice is carbon dioxide in solid form. It melts directly to gaseous form, with no liquid form in between. Because it's very cold, handle it with gloves.
When you place dry ice into hot or warm water, you get clouds of white fog. The fog is not carbon dioxide gas, but condensed water vapor. Because it's combined with invisible carbon dioxide gas, it's heavy and can be poured like liquid.
Experiment to see how much fog you get from various amounts of dry ice. With a pound of dry ice, you can create enough heavy fog to cover the floor of a medium-size room. Keep pets and children out of the fog, because carbon dioxide gas has a suffocating effect.
Crystals
There are many kinds of crystals, among them salt, sugar and diamonds. In this experiment, you grow crystals using recrystallization, a method in which a substance is dissolved in hot water and the mixture is then cooled.
Use water and borax. As the mixture cools, the borax will gradually appear as crystals. The crystals grow because of saturation; i.e., when no more solid can dissolve in the water, solid pieces form and, over time, collide, combine and grow larger, forming crystals.
What sizes and shapes of crystals will you get when, during the cooling phase of recrystallization, you grow them either in an ice bath, in the refrigerator or at room temperature? Warmer temperatures can help with crystal growth because of evaporation, but cooler temperatures can help get the process started more readily because cold slows molecule movement, thus increasing bonding. Test for optimal temperature conditions, then compare your results.
Perfumery
This experiment will demonstrate extract perfume from flower petals through a method known as enfleurage, and how changing the variables of the process will alter the scents.
Over time, solid, odorless fats can trap sweet-smelling constituents secreted by plant material. To perform enfleurage, use vegetable shortening to absorb the aroma of the petals, then use alcohol to extract the fragrance from the oil.
Construct a hypothesis about how many cycles of enfleurage you'll need to come up with a pleasing scent that is similar to that of the flowers whose petals you used. Repeat the experiment to discover how the scent is altered if you let the flower petals sit in the oil for longer or shorter periods of time. You may also try butter instead of vegetable shortening to see how it affects the fragrance.
Electrolytes
During strenuous exercise, the body loses electrolytes, which must be replaced because the heart and nervous system require electrolytes in order to operate properly. Once replaced, electrolytes are maintained by the body in a balanced concentration.
Sports drinks are marketed as a good way to replace electrolytes lost through exercise, so experiment to determine whether sports drinks contain more electrolytes than orange juice. You can do this with a multimeter, an instrument that measures electrical current. The level of conductance shown by the multimeter reveals which -- sports drinks or orange juice -- has the greatest proportion of electrolytes and is thus the best choice for electrolyte replacement. You can also compare various sports drinks.
Tags: carbon dioxide, flower petals, orange juice, sports drinks, temperatures help, vegetable shortening