Investigating the Effect of Concentration on the Rate of Diffusion
Aim: To find out if concentration affects the rate of diffusion.
Prediction: I predict that the higher the concentration of acid the
faster the reaction will be.
Hypothesis: Diffusion is the spreading out of a gas or liquid from an
area of low concentration to another area where it has a lower
concentration until the overall concentrations are balanced. The
Hydrochloric acid (HCl) diffuses into the gelatine cube of which
contains Sodium Hydroxide (NaOH), which is an alkali. When the
Hydrochloric acid combines with the Sodium Hydroxide they form salt
and water, which is neutral therefore turning the pink cube to clear.
Dependent variable: We are measuring the time taken for the pink
indicator to turn clear when hydrochloric acid is added to it.
Independent variable: We are changing the molar of hydrochloric acid
we are adding to the gelatine cubes. The molars range from 1-3.
Apparatus:
* 1 measuring cylinder
* 1 test tube
* 1 stop clock
* A large gelatine cube containing indicator and NaOH
* Hydrochloric acid ranging from 1-3 molars
* A scalpel
Diagram:
Method:
* Take the large gelatine cube and cut into 15 equal pieces
* Place on piece of the cube into the test tube
* Measure out 10mls of HCl in the measuring cylinder
* Pour the HCl into the test tube with the gelatine cube and start
the clock
* Time how long it takes for the pink colour inside the gelatine
cube to completely disappear
* You will also notice that the cube dissolves slightly
* Record your results and repeat this same process 3 times for each
molar of acid:
§ 1 molar
§ 1.5 molar
§ 2 molar
6. Drop one tablet in the beaker and time how long it takes to fully dissolve
The Effect of Solute Concentration on the Rate of Osmosis Aim: To test and observe how the concentration gradient between a potato and water & sugar solution will affect the rate of osmosis. Introduction: Osmosis is defined as, diffusion, or net movement, of free water molecules from high to low concentration through a semi-permeable membrane. When a substance, such as sugar (which we will be using in the experiment we are about to analyse), dissolves in water, it attracts free water molecules to itself, and in doing so, stops them from moving freely. The effect of this, is that the concentration of (free) water molecules in that environment goes down. There are less free water molecules, and therefore less water molecules to pass across a semi-permeable membrane, through which sugar molecules and other molecules attached to them are too big to diffuse across with ease.
The first step that we took to accomplish our goal was to put on our safety goggles and choose a lab station to work at. We received one 400ml beaker, one polyethylene pipet, two test tubes with hole rubber stoppers, two small pieces of magnesium (Mg), one thermometer and a vial of hydrochloric acid (HCl). We took the 400ml beaker and filled it about 2/3 full of water (H20) that was 18 OC. Then we measured our pieces of Mg at 1.5 cm and determined that their mass was 1.36*10-2 g. We filled the pipet 2/3 full of HCl and poured it into one of the test tubes. Then, we covered the HCl with just enough H2O so that no H2O would be displaced when the stopper was inserted. After inserting the stopper, we placed the Mg strip into the hole, inverted the test tube and placed it in the 400ml beaker. HCl is heavier than H2O, so it floated from the tube, into the bottom of the beaker, reacting with the Mg along the way to produce hydrogen gas (H2). We then measured the volume of the H2, cleaned up our equipment and performed the experiment a second time.
* We would have to leave one end open to fill it up with the different
We cut three potato chips to an equal length and then we set up 3
...is for this experiment is: “If you increase the amount of drops of bleach mixed into a blue dye solution, then the total amount of time for the blue dye in the solution to disappear will decrease.” In other words, I think that the blue dye in the solution will disappear faster when you increase the amount of bleach. The research that I gathered helped me understand better of why and how I am going to do my experiments in the way I am doing them. It also supports my hypothesis. It supports my hypothesis because I found out that there is an active ingredient in bleach known as the hypochlorite molecule. This molecule helps break the bonds in pigment molecules so I think that the more bleach used, the faster the bonds will break apart. In this experiment, I will be finding out how much dye are mixed in sports drinks and what is the reaction rate of bleach and blue dye.
The Importance of Diffusion to Living Organisms Diffusion is basically the movement of chemical species (ions or molecules) under the influence of concentration difference. The species will move from the high concentration area to the low concentration area till the concentration is consistent in the whole system. Diffusion mostly occurs in gases and liquids as these can move freely. The main features of an efficient diffusion system would be that it has a large surface area, thin membrane and a continuous supply of substances. A large surface area is needed so that high amount of substances can be exchanged at a time while the thin membrane means that the diffusion pathway would be short so that it is more efficient.
It is important however to note that the NH4 and K ions are still in
Diffusion and osmosis refer to passive transport systems where molecules and ions move down concentration gradients driven by thermal motion. The concentration gradients are setup in solutions in living systems that are separated by biological membranes. Diffusion refers to the spontaneous movement of particles, molecules, or ions from an area of higher concentration to an area of lower concentration. The process occurs slowly without any expenditure of energy. Diffusion occurs in liquids and gases. An example of diffusion is the movement of the smell of a spray from the point of spraying to the rest of the room. On the other hand, osmosis refers to the movement of molecules of a solvent such as water from an area of low concentration to an area of higher concentration. It is a special type of diffusion that occurs in reverse. An example of osmosis is the process through which animal cells feed on the food they partake. Thus, diffusion and osmosis are called passive transport systems because they enable cells of living systems to move molecules in
How Concentration affects the rate of reaction I am investigating the rates of reaction and how the different variables can affect it. I know that the temperature, a catalyst, concentration, the surface area, light and pressure of a gas can affect the rate of reaction. In this particular experiment I am going to investigate on how the concentration of one of the reactants affects the rate of reaction. To show that the concentration does affect the rate of reaction I am going to carry out the reaction of sodium thiosulphate and hydrochloric acid. The reactant I am going to change in concentration for each experiment/reading is sodium thiosulphate.
Dependent Variables Amount of vitamin C in fruit juices. Controlled Variable Same amount of liquid for each fruit juice.... ... middle of paper ... ...
According to the results shown, 2 M hydrochloric acid that was more concentrated had a faster rate of reaction than less concentrated 0.5 M hydrochloric acid. As could be seen from Figure 1: processed data, 2 M hydrochloric acid’s average water displacement of 9.1 cm was much larger than 0.5 M hydrochloric acid’s water displacement of 0.3 cm. Therefore, the trend of the reaction rate increasing as the concentration increased was shown. The hypothesis was supported by the evidence obtained from this experiment.
I blended on high to make the potatoes more liquid-like. I grabbed the cheesecloth and placed on the top of the blender. I poured the potato extract on the container and labeled it. I found out that I have to make 1% sugar solution so I grabbed the sugar and measured into 5 grams on the scale. I added 5 grams of sugar on 250 ml graduated cylinder and poured the water into the cylinder. I mixed the sugar with water and poured it into the saucepan. I refilled the water into the graduated cylinder and poured into the saucepan. I turned on the heat of the stove and saw the sugar dissolved. I poured into a container and labeled 1% sugar solution. I repeated the same thing with 1% salt solution by using 1 gram of salt and filled the water into graduated cylinder by 100 ml. I answered question three. In the first experiment, I grabbed four transfer pipets and used it to put solutions into the test tubes by 3ml. I labeled it and placed into the plastic cups so it can stand upright. I grabbed each test tube and poured 2 ml of catalase solution into it. I also tapped and swirled to measure the bubbles by using the ruler. I wrote the numbers into the lab report. In the second experiment, I labeled the room
the chances of collisions increase thus giving a faster rate of reaction. Then the s Apparatus:. Beaker Hydrochloric acid Distilled water Measuring cylinder Pipette Test tubes Test tube rack Diagram:.. [ IMAGE] Method: The.. Measure out 10cm3 of hydrochloric acid, as the concentration requires. for each concentration its composition is.
In this experiment we are trying to identify an unknown acid or base and its concentration by using the method of titration. The pKa values and the titration curve help aid in identifying of the unknown. In our case we had a base as our unknown (analyte). The use of a certain amount of sodium hydroxide and hydrochloric acid will be used to titrate the unknown solution that is given. This is the tirant. We used hydrochloric acid as our titrant. We achieved a pH of 5.56 at an end point of 10 milliliters. The unknown’s concentration was around 0.098 M at pka(s) of 6 and 7. The sodium hydroxide and hydrochloric acid are called titrant and it is contained in a container called burette. The unknown solution is held in an erlenmeyer flask. The purpose of the experiment is to measure the weak acid and base by neutrilizing it and determining the unknown acid by titration.