Lab2

INSTRUCTIONS:
· On your own and without assistance, complete this Lab 2 Answer Form electronically and submit it via the Assignments Folder by the date listed on your Course Schedule (under Syllabus).
· To conduct your laboratory exercises, use the Laboratory Manual that is available in the WebTycho classroom (Reserved Reading or provided by your instructor) or at the eScience Labs Student Portal. Laboratory exercises on your CD may not be updated.
· Save your Lab2AnswerForm in the following format: LastName_Lab2 (e.g., Smith_Lab2).
· You should submit your document in a Word (.doc or .docx) or Rich Text Format (.rtf) for best compatibility.

Experiment 1: What Household Substances are Acidic or Basic?
Table 1: pH values of common household substances
Substance|pH Guess|pH Paper|
Vinegar|2|~3|
Sodium bicarbonate solution|8|~7.5| Milk|7|~6.5|
Orange Juice |5|~3.5|
Hand soap |8|~9|
Lemon juice |4|~2.5|
Questions
1. Compare and contrast acids and bases in terms of their H+ ion and OH- ion concentrations.
Vinegar – Acidic with a low pH of around 3.
Sodium – Basic – with a higher pH scale around 7.5
Milk – I thought would be basic but it’s actually more acidic, around 6.5
Orange Juice – Acidic actually around 3.5
Hand soap – Basic around 9 pH
Lemon juice - most acidic thing I tested around 2.5
2. Name two acids and two bases you often use.
Acids: I drink Orange Juce everyday along with milk.
Basics: Hand Soap and toothpaste

Experiment 2: The Effect of Surface Area and Volume

Table 2: Results from surface area to volume experiment
Cube Dimensions|Surface Area (cm2)|Volume (cm3)|Surface Area : Volume|Time Require for Complete Color Change|Distance of Diffusion|
1 cm x 1 cm x 1 cm|6cm2|1cm3|6:1|4|3/4|
1 cm x 2 cm x 2 cm|16cm2|4cm3|4:1|5|full|
1 cm x 1 cm x 6 cm|26cm2|6cm3|13:3|3|1/2|
Questions
1. How did the surface area affect the diffusion of the cube? What about the volume? What about the surface area to volume ratio? Which of these had the greatest effect on the diffusion into the cube?
The more the surface area, the longer it took for the stuff to diffuse. Same with the volume. The volume had the greatest effect on diffusion.

2. How does this experiment demonstrate the need for larger cells to divide?
The larger cells need to divided because the bigger they are, the less nutrients they can transport and send out the waste.

3. For the three cubes shown below, determine their surface area, volume and surface area to volume ratio. Then, circle the one you believe would be the most efficient and write a summary stating why.

I would chose the middle block because it has the smallest volume of 1.5. The larger the volume the harder it is to transport nutrients and get the waste out. Therefore, its not too big so it can still transport nutrients between the different areas of the cells and still abosorb the right amount of nutrients.