Matter Lab

The objective with this experiment was to get more familiar with elements and compounds. An example of an element would be tungsten which cannot be broken down into simpler substances by any chemical or physical means. Compounds are simply composed of two or more elements such as sodium chloride or table salt (NaCl). Chemical changes are able to break down most compounds to their original components. Mixtures are also another form of matter that are classified as either homogeneous or heterogeneous. Homogenous mixtures are consistently uniformed throughout the substance such as lemonade or salt water. You cannot see any separation. Heterogeneous mixtures are not uniform in composition. Examples are sand water and oil and vinegar dressing. Therefore, throughout this experiment we will learn chemical name and symbols and learn to classify between the mixtures, elements, and compounds. We will observe chemical reactions and learn separation techniques.

The first part of the lab was separating a mixture of elements and compounds. We started by taking the mass of four substances as close to five grams as we could get. The substances were iron, zinc, sand, and sodium chloride. Observations were made for each substance after we obtained them. The iron was odorless, brown in color, and finely cut. The zinc was solid and hard, grayish-white in color, and had large fragments. The sand was like any other sand, tan with black specks. The sodium chloride had a salty odor with white crystals. The only magnetic substance was the iron.

Combining all four substances that were mixed heterogeneously we weighed them in a pre-weighed beaker and recorded them. Observations were then taken of the newly formed mixture. The newly formed mixture was moved to a clean weighing boat and tested with a magnet to remove all magnetic material. The iron, which was the only magnetic substance to begin with was the majority of the mixture with bits of sand involved. It was reweighed and recorded. Next, we sifted the remaining mixture into a 400 mL beaker. The zinc which had large fragments were recovered by the screen and reweighed. The sand and sodium chloride that were sifted into the beaker were reweighed and recorded. After recording the sand and sodium chloride mixture, deionized water was added and mixed gently. The observation we saw was the water became murky with the salt and sand.

Filtration was the next part of the lab we learned how to do. With our filter paper ready and funnel in an iron ring clamped to a ring stand. We weighed an empty 250 mL beaker and recorded the mass. The contents of the sand and salt were then poured into the funnel and recorded observations were made. The contents of the beaker was slightly cloudy water. The filter paper had obtained a lot of wet sand. I believe the sodium chloride was funneled into the beaker along with the water because the crystals in salt can be dissolved in water. That is why the water was cloudy. The sand was caught in the filter paper because sand tends to clump up when it becomes wet and also cannot be dissolved in water. The filter paper was then put in the oven along with the substance to dry where its mass was recorded after drying. With the hot plate turned on to 300 degrees Celsius, we put on the 250 mL beaker with the salt substance and let most of the liquid evaporate. After the beaker cooled down, the contents were examined and recorded. The material identified were large chunks of salt crystals. The weights of the beaker and separated material were recorded along with the separated material itself. I have a few tables for you to look at.

Substance Initial mass in grams Final mass in grams Percent Yield

Iron (Fe) 5.01 g 5.20 g 96.3%

Zinc (Zn) 5.02 g 5.02 g 100%

Sand (SiO2) 5.09 g 10.18 g 50%

Sodium Chloride (NaCl) 5.20 g 10.18 g 51.1%

Observations Before Mixing

Substance Observations of Physical Properties

Iron Magnetic, odorless, brown in color, finely cut

Zinc Solid, hard, grayish-white in color, large fragments

Sand Tan with black specks, not magnetic

Sodium Chloride White crystals

Observations After Mixing

Substance Observations of Physical Properties

Step 4 Beaker- 133.46 gramsBeaker with substances- 153.85 gramsMixed heterogeneously

Step 5-6 Mass of magnetic substances (mostly iron)Observation- slight amounts of sand

Step 7-8 Pour remaining mixture onto screen sifting