     Density of Minerals
Task with Student Directions

Contributed by: New York State Education Department (NYSED)
NYS Alternative Assessment in Science Project (1996)

At this station, you will be determining the mass, volume and density of two (2) mineral samples. Data and calculations will be recorded precisely and accurately within the limits of the measurement tools.

### Materials:

• metric balance
• overflow cup
• beaker with water
• mineral samples A and B
• calculator

### Background:

Minerals are the different materials which make up the various rocks of the earth. Each mineral has its own set of identifying properties. Density is one of the properties often used to identify minerals. Rocks are one or more minerals which have been put together in different ways. The properties of the rocks, made of the same minerals, may be different depending on how the rocks were made. Mineral densities are nearly always the same.

### Directions:

1. Record the code number of each mineral sample and find the mass of each to the nearest tenth of a gram.

 A. Code Number ____________ Mass _______________ B. Code Number ____________ Mass _______________

2. Record the code number and find the volume of each mineral sample to the nearest whole cm3 (ml).

 A. Code Number Volume _____________ B. Code Number Volume _____________

3. In the space below, describe the procedure you used to find the volume of the minerals.

4. What is the density of the mineral samples? Record you answers to the nearest tenth place.

 A. Code Number ___________ Density _____________ B. Code Number ___________ Density _____________

Show your work in the space below.

 Mineral sample A Calculations Mineral sample B Calculations

5. The metamorphic rock Quartzite and a sedimentary rock sandstone are both made of the mineral quartz that has a density of 2.65 grams/cubic cm (g/cm3). A geologist determined the density of a sample of quartzite to have a density of 2.65 grams/cubic cm, and determined the sample of sandstone to have a density of 2.45 grams/cubic cm.

A. In complete sentences, explain why the sample of quartzite has a different density from the sample of sandstone.

B. In complete sentences, explain why densities of the quartz and the sample of quartzite are the same.  