TITLE: Toxicity Tests and Deciding the LC50
ADVANTAGES: Our main objective just for this experiment was to determine which usually three chemical substances were the most dangerous to the bout shrimp with the addition of drops of vinegar, whiten and freezing mixture to the handled water. We found the fact that vinegar was the most effective as well as the quickest. The ending outcome was very interesting when ever being in comparison to our hypothesis and we learned that some chemicals can respond faster than others and contains another type of level of attention. HYPOTHESIS: Intended for brine shrimp exposed to elevating concentrations of three chemical compounds, ammonia could have the highest LC-50 (toxicity), bleach will have the intermediate LC-50 (toxicity) and vinegar will have the lowest LC-50 (toxicity). MATERIALS AND STRATEGIES: For this experiment we make use of the following materials: Petri dishes (4 every group)
Stop watch or time
Safety eye protection (1 for each person)
Section solution (3. 5% w/v NaCl and water) need 600 milliliters per class Vinegar- require about 60 ml in small dropper bottle (1 per group) Ammonia- want about 50 ml in small dropper bottle (1 per group) Bleach- will need about 60 ml in small dropper bottle (1 per group) 3 pipettes (1 ml) – every labeled to get the respective contaminants Pipette pumps
Beakers (5 or 15 ml)
Managed to graduate cylinders (25 ml)
Magnifiers or hands lens (minimum 2 every group)
Beakers (Extra large) for waste- one every labeled to get Vinegar, Bleach and Phosphate Beaker (Extra large) intended for tested Brine Shrimp
Each of our procedures contains eight methods.
Step 1- Most of us put on the safety eye protection before gathering our materials. Step 2- We accumulated our 5 petri dishes and labeled them by using a grease pencil. One petri dish marked " C” for Control, " V” for White vinegar, " A” for Ammonia and " B” to get Bleach. Stage 3- Once the petri meals were tagged, we took a 25 cubic centimeters cylinder and used a pipette to gather 12 bout shrimp to set inside of the canister. Using the way of measuring lines on the side of the cylinder, we had to make certain the way of measuring of water and bout shrimp reached a level of 20 ml. Once we obtained exactly 12 brine shrimp, we after that dumped the contents of the cylinder, such as brine prawn, into the petri dish tagged " C'” for control. We continuing to use the pipette to gather 12 section shrimp and measured the extent to 20 milliliters for each of the other petri meals until every single petri dish contained 12 brine shrimp each. Step 4- Ahead of adding any of the concentrations for the petri food, we put the lids in all four with the petri dishes and set our stop watch to get 5 minutes to see the brine shrimp in their managed atmosphere. When 5 minutes concluded, we after that counted the quantity of live section shrimp and recorded the information on a chart for each person petri dish. This was extremely important because section shrimp are known for cannibalistic behaviours and shedding a section shrimp to cannibalism could throw off the count of live prawn after the concentrations have been added. Step 5- We reviewed how efficient we thought each focus would be for the brine prawn. Our speculation was that ammonia will have the best LC-50 (toxicity), bleach will have the more advanced LC-50 (toxicity) and white vinegar will have the minimum LC-50 (toxicity). Step 6- Once the hypothesis was made, we gathered each of our dropper wine bottles of hydrogen, vinegar and bleach. Leaving the " C” (control) petri dish aside, all of us began adding the proper chemical compounds to the designated petri dish using a clean pipette pump assigned with each chemical. Each individual was responsible for one petri dish for the reason that chemicals had to be added concurrently to receive accurate benefits. The petri dish branded " V” was given 0. 5 cubic centimeters of white vinegar, the petri dish labeled " B” was given zero. 5 milliliters of bleach, the dish labeled " A” was handed 0. five ml of ammonia at the same time and then we all gently swirled the water in the petri dishes and quickly replaced the lids and started the stop watch for 5 mins. Step 7- Once five minutes...