Name:

Period:

Marine Science Project

Probing into the Unknown

Introduction

This project will take place over a period of 6 days. Upon completion of this project you will have a better understanding of the scientific process as well as the factors in the environment affecting the processes of living things. This lab packet will provide a place for you to organize and record your information. As you complete the experiments you may use this packet to record data, answer questions and form conclusions.

Project Schedule

Pre-Activity Assignment

Define the following vocabulary terms. In addition to defining each term use the word in a sentence or give examples whenever possible.

Vocabulary

1.   element

2.   compound

3.   acid

4.   base / alkalinity

5.   ions

6.   pH

7.   solute

8.   solvent

9.   solution

10.         dissolved oxygen

11.         photosynthesis

12.         biotic

13.         abiotic

14.         salinity

15.         soluble

Questions

1.   Why is scientific method a useful way to solve problems?

2.   A pH of 6.5- 8.2 is optimal for most organisms. Predict what might happen if the pH level of a lake suddenly increases to 11.0.

3. Your best friend Marc has left for vacation and will not return for several months. Unfortunately he left in a hurry and forgot to ask someone to take care of his saltwater aquarium. Marc phones you from the airport and asks you to take care of his fish while he is away. Now you must do your own research on how to care for a saltwater aquarium. Get to work!!!!

Objectives

·       Introduction to elementary chemistry terms.

·       Gain a better understanding of the properties and chemistry of water.

·       Explain the properties of water as a solvent.

·       Understand the importance of abiotic factors and their effect on biotic factors.

·       Using scientific techniques collect and organize information in a brief and concise manner.

·       Practice making observations and describing the characteristics of each unknown substance.

·       Formulate hypothesis to explain the type and origin of each unknown substance.

·       Practice developing conclusions and writing brief experimental reports.

Day 1

Materials: Students should check the material box located at each station. The following materials are in the box labeled materials or on the desk. If you are missing any materials please see your teacher immediately.

1.   Unknown substance A

2.   Unknown substance B

3.   Unknown substance C

4.   100 ml. graduated cylinder

5.   markers

6.   3 baby food jars with lids

7.   tablespoon

8.   distilled water

9.   paper cups

10.         cone filter paper

11.         200ml beaker or larger

12.         pH probes

13.         Computer and Vernier computer interface

14.         Logger Pro

Preparing your computer

1.   Double click on the Icon Logger Pro.

2.   File Open

3.   This screen will allow you to choose from a list of folders. Highlight Middle School with Computers and choose the file labeled soil study. Click choose.

Procedure

1.   Observe the color and texture of the three unknown substances. Record your observations in the appropriate place in Table 1.

2.   Place 2 tablespoons of substance A in a baby jar and add 50 ml. of distilled water. Tightly close the lid and shake vigorously for 60 seconds. Leave the jar undisturbed for 5 minutes.

3.   Remove the pH sensor from the container and safely store the container inside the material box.

4.   Rinse the pH probe in a cup with distilled water.

5.   Place the pH sensor in substance A and swirl the sensor around in the substance until the readings are stabilized. (Your teacher will explain the term stabilization).

6.   Once the readings have stabilized click keep. Type in A in the window labeled sample.

7.   Repeat steps 2 through 6 for substance B and C.

8.   Save your graph and data.

Important Points:

·       The pH sensor must be rinsed in distilled water each time a sample is tested. This step is extremely important in order to avoid contamination.

·       Once you have tested the pH of all the unknown substances rinse the pH sensor in distilled water and return it to its appropriate protective container.

Part II: Water Absorption

Procedure

1.   Place 2 tablespoons of unknown substance A in a filter cone.

2.   Place the filter paper in a beaker and pour 50 ml. of water through the soil. Wait 60 seconds.

3.   Measure the amount of water in the bottom of the beaker. Subtract 50 ml. from the measured amount and record this in the appropriate place in Table 1.

4.   Repeat steps 1-3 for substance B and C.

Data Table 1

Sample

Description/Observation

pH

Water volume before absorption

Water absorbed

A

50 ml.

B

50 ml.

C

50 ml.