(solution) EXPERIMENT 4 The Separation of a Heterogeneous Mixture Objective

(solution) EXPERIMENT 4 The Separation of a Heterogeneous Mixture Objective

EXPERIMENT 4

The Separation of a Heterogeneous Mixture

Objective:

To separate a mixture of sand and table salt (sodium chloride, NaCl)

Introdution:

Matter is made up of anything that occupies space and has mass (weight). There are two types of matter (1) homogenous and (2) heterogeneous. Homogeneous mater has a uniform set of properties, where heterogeneous have different sets of properties. An example of homogeneous matter is vanilla ice cream. An example of heterogeneous matter is chocolate chip ice cream, several different types of properties.

Materials Needed:

100 mL Beaker

Thermometer

Sodium chloride (NaCl)

Sand

Weighing boats

Procedure:

1. Using your electronic balance weigh out about 1 gram of table salt (NaCl) and two grams of sand. Record the mass to two decimal places. Record the weights of report form REPORT FORM (1) and REPORT FORM (2).

2. Weigh a 100 mL beaker. (REPORT FORM (3)

3. Shake the mixture in a test tube. Add the mixture to the weighed 100 mL beaker (make sure all the sample gets transferred).

Extraction of NaCl:

4. Add 10 mL of warm water (water temperature should be above 30oC) to the beaker. Stir for about 2 minutes. Decant (remove the liquid and keep the solid) the liquid to another beaker. Repeat this process with another 10 mL of warm water. Stir and decant. Repeat two more times to remove all the NaCl.

5. Put the remaining sand into one of the weighing boats. Make sure all the sample is transferred. Let dry for three days. Weigh the sand sample and record it on the form. (REPORT FORM 4)

6. Let the water evaporate (it may take several days). What remains is the solid NaCl. Weigh the beaker and the dry NaCl. (REPORT FORM 5)

7. Subtract the weight of dry beaker from beaker with NaCl. (REPORT FORM 6)

EXPERIMENT 4: Separation of Heterogeneous Mixture

REPORT FORM: Name ________________________

Date _________________________

1. Mass of sodium chloride (NaCl) ______________ g

2. Mass of sand ______________ g

3. Mass of 100 mL beaker ______________ g

4. Mass of dry sand sample ______________ g

5. Mass of beaker and dry NaCl ______________ g

6. Mass of dry NaCl ______________ g

Question:

Does the mass of NaCl on REPORT FORM 1 and 5 obey the Law of Conservation of Matter and why?

How about the initial and final sand weights? Are they the same? Explain why and determine the pre cent error.