# Homework Help - "Analyzing a sand sample"

#### Breakdown

##### Diabloii.Net Member
Homework Help - "Analyzing a sand sample"

I'm having some trouble in my bio class and this is one of the assignments. (lab report)

The objective is to find out what materials are contained in a sample of sand.

Procedures:
1. You will conduct four tests to help determine what materials comprise your sand sample. The first test will be conducted using your eyes or a magnifying lens; The second will use a test tube, alcohol burner, (similar to candle) and heat. And the Third will be using water.

2. Examine the sand you recieve. Record the descriptions of the grains. (Test One) My Observations - The sand is white and smooth and contain small grains.

3. Next, pour the sand into a dry test tube. Heat it over the alcohol burner for five minutes. Record your observations (Second Test) My Observations- As i was heating the sand, it became darker. It seemed to become more and more dense. It formed 3 layers of different colors.

4. After the test tube is cool, for about another 5 minutes, hold the bottom of it in one hand and add five to ten drops of water to the sample. Observe and record. (Test Three) My Observations - The sand sample seemed to heat up again after adding the drops of water.

5. Add more water until the sand is covered by about a centimeter of water. Put the sand water mixture into the Petri dish. I did not get a chance to observe this part yet.
Now for the main course, "Data Questions"
This is the part im having problems with so i need your help

1. Identify the following: control, independent, and dependent variables

The Independent variable is the one that is changed by the scientist. In an experiment there is only one independent variable.

The Dependent variable changes in response to the change the scientist makes to the independent variable. The new value of the dependent variable is cause by and depends on the value of the independent variable.

Controlled variables are quantities that a scientist wants to remain constant, and he must observe them as carefully as the dependent variable.

2. After observing the original sample of sand, do you think the grains are of the same material or of different substances? Explain your answer

3. What effect did heat have on the sample?

4. Do the results of heating change your answer to question 1? Give reasons why?

5. Name one substance you think the sand sample contains.

6. What do the results of the entire investigation tell you about the composition of the original sample of sand?

7. What do the results of this investigation tell you about the possible effect of heat on the composition of the sample

Well those are the questions, and there a pain in the *** for me.. I understand by not doing this experiment firsthand is hard. But it would be great if you guys helped out. Thanks again

#### AeroJonesy

##### Diabloii.Net Member
You want us to do your homework? Do you not realize we all hated doing our own homework? Doing yours looks even less fun.

Can't you answer these questions based on the lab? I fail to see what's so difficult about answering the questions - unless you skipped the lab, or just didn't pay attention in class.

#### Breakdown

##### Diabloii.Net Member
AeroJonesy said:
You want us to do your homework? Do you not realize we all hated doing our own homework? Doing yours looks even less fun.

Can't you answer these questions based on the lab? I fail to see what's so difficult about answering the questions - unless you skipped the lab, or just didn't pay attention in class.
yes i did pay attention in class. the only question im not having problems with is the second one. and the rest im totally lost..

#### AeroJonesy

##### Diabloii.Net Member
For question 1: What did you change? That is, what were you controlling in the experiment? The mass of the sand, the amount of water added, the temperature of the sand?