The research question for the Alka Seltzer Lab is, “What is the effect of different surface areas of an Alka Seltzer tablets reaction time?’. Inside of an Alka Seltzer tablet there are two key ingredients; which are citric acid and baking soda. When a tablet is dropped into a liquid, the acid and baking soda show a physical reaction of fizzing and eventually dissolving. Materials needed for this lab was goggles, aprons, beakers, water of the same temperature, mortar pestle, and three alka seltzer tablets. In each beaker there was 150 mL of water. The first tablet was a full tablet, the second was broken into quarters, and the last tablet was crushed in a mortar pestle. The dependent variable of the lab was the rate of reaction, and the independent
* In every experiment there are variables that affect the way an experiment will go. The three types of variables that are measured are Independent, Dependent, and Controllable variables. In my experiment the Independent variable is the three different models of paper airplanes that I have chosen to make and experiment with. The Dependent variable includes the distance the paper airplane goes. The Controlled variable is me making sure that I throw the paper airplanes from the same starting point a well as the same weather conditions. The controlled variable is the one that cannot be changed because it would affect the other two variables. In this case I threw them in my house since I have a very long hallway that leads into the front family room and there is no furniture that would interfere with the results.
The independent variable for the experiment was the paper towels. The dependent variable was the absorbency and strength. The constants for the experiment were the size of the paper towels that were used, the amount of water, the size of the beaker, the size of the cylinder and the amount of the weight.
1. For this experiment, what were the independent variable and the dependent variable? What were the constants?
The Dependent variable for this study is the amount of water absorbed by the paper towels. This will be measured in milliliters. The independent variable for this study is different brands of paper towels. The controlled variables will be the amount of water the paper towels are given to absorb, the size of the paper towels at the beginning of the experiment, and using the same measuring instruments in each trial. I will reduce the threat to internal validity by conducting the experiments in the
4. The Independent variable is the dissolved oxygen and the dependent variable is the number of fish observed.
There are several parts to the experiment such as both the independent and dependent variables. The independent variable is controlled or changed during the experiment to test the effects on the dependent variable. The dependent variable is tested and measured during the test .A controlled variable is an example for an independent variable would be variable that is held constant throughout the experiment. An example is a theory that could extend a person’s life expectancy. The independent variable is the amount of vitamin given to the subject within the experiment. The dependent variable is the life span
I filled three clear cups, the first one with dH2O, the second with 0.1% NaHCO3 solution (equal parts 0.2% NaHCO3 and dH2O), and the third with 0.2% NaHCO3 solution. The control of the experiment is the cup with dH2O. The independent variable is time and the dependent variable is the number of disks floating in the solution. We separated the 30 disks into three groups of 10, placed them in syringes filled with a corresponding solution (either dH2O, 0.1% NaHCO3, or 0.2% NaHCO3), and removed all air from the syringe. This causes photosynthesis to stop in the disks, which then causes the disks to not float any longer. The three groups of disks were placed in each cup filled with 100mL corresponding to the solution, then placed under a light source and started a timer. For each minute in 15 minutes, data regarding the number of disks that floated to the top of each
Dependent variable- jar volume after the egg is out (ml). Controlled variables- jar, same amount of water and corn syrup, same number of days it stayed there, same grade egg, same process, same surface we put them on. The experimental group are both the eggs because they both got tested on. We didn't have a control group because we didn't have an egg that didn't go through a test. The experimental group is the group you experiment on. The control group which doesn´t get tested
Independent variableIdentify the independent variable (IV), which is the variable that you hypothesize will cause or influence the other variable. *
The primary purpose of the lab was to test and observe the effects of the process of osmosis on decalcified eggs. Before the process, the initial weights of the eggs were taken and noted. Two eggs were then immersed in a deionized water solution. The same was repeated to the other two solutions of 20% and 40% sucrose. The weights of the eggs were measured after 15 minutes to note the change in mass due to osmosis and again after 60 minutes to take the final measurement. Overall, while some human error might arise in the weighing process, care was taken in handling the eggs and during the weighing process. As such, it was found that the eggs behaved as predicted. It was found that the eggs placed in the hypertonic solution lost
Variables: In this experiment, the temperature (in degrees Celsius) of the chemicals is the independent variable. To change the temperature, the materials are placed in a bath of water being heated by a hotplate.
Independent variable: We will change the amount of drops of Hydrochloric acid added to the Amylase. ( 5 drops, 10 drops, 15 drops)