REFERENCES GENERAL CHEMISTRY FOR ENGINEERING AND SCIENCE II CHE 152-50 Factors Which Influence the Rates of Reactions pages 1-10 OBJECTIVES To examine the factors which cause the rate of chemical reactions to change. QUESTION The question that was proposed for investigation was: Do all factors change the rate equally? Background Discussion For this experiment you have to have a basic understanding of Collision Theory to understand what’s going on in the experiment. Collision Theory is a model of chemical reactions in which a reaction occurs after a collision containing enough energy occurs between two reactant molecules. This model has five factors which can be affected and they are the nature of …show more content…
In the final part of phase one which was steps 9-11, five different metals were placed in Hydrochloric acid. The five metals were copper, magnesium, lead, iron and zinc. Magnesium was the first to react and it created bubbles before it completely dissolved in the acid. Zinc was extremely reactive and produced a lot of bubbles. Iron started reacting after zinc and created some bubbles. Then slowly lead had produced a few bubbles and copper didn’t make any (Lab Guide pg.2). Next in phase two of the experiment which was titled Concentration and that was steps 12-14. In this phase 3 wells were filled with different concentrations of 6m HCL. The first well contained 60 drops of water and 20 drops of acid. The second one contained 40 drops of water and 40 drops of acid and the final well contained 80 drops of acid. After each of the wells were stirred a piece of clean zinc was placed into each of them. Well three almost immediately produced smoke with a lot of bubbles. Well 2 reacted soon after with a lot of bubbles and lastly Well 1 reacted creating some bubbles (Lab Guide pg.3). Then in phase three which was titled Temperature and that was steps 15-18, clean zinc was placed in three different test tubes containing 5ml of 6M HCL, each of which was a different temperature. Test tube one was placed in boiling water, Test tube 2 was at room temperature and test tube three was placed in an ice bath. When the zinc was placed in test tube 1 it reacted quickly and
1.What two factors did you investigate in your procedure, and why did you choose to compare these two factors?
3. Test the effect of a magnet on each substance by passing the magnet under
2. Obtained a 2-3 cm strip of magnesium metal ribbon and coiled it loosely into a small ball. Added the magnesium metal to the acid in the test tube.
either barium (Ba 2+ ) or calcium (Ca 2+ ). Part C consisted of a series of cation flame tests using metal
If you see a deep blue color add more zinc powder until there is no change in color of the solution in the test tube.
The solution had an opaque image, meaning if you were to look through the mixture you would only see a light blue liquid, thus the solution was not transparent. Furthermore, the solution from the Copper Chloride and Water dissolved together had demonstrated one solid colour- thus the light blue colour from the solution was spread evenly through the beaker and no other particles were visibly seen.
The main objective of this experiment is to differentiate between a physical change and a chemical change.
When the zinc was dropped in the hydrochloric acid, the substance began bubbling vigorously, forming a precipitate. Eventually, the zinc dissolved completely. After the lit wooden splint broke the surface of the test tube, there was a loud popping noise. The gas that was released was hydrogen from the acid and the popping noise was a result of the Hydrogen being burned up by the fire creating a small explosion. Two chemical changes occurred in this test: one with the formation of a precipitate (a textbook sign of a chemical change), and the other when the explosion
This is a fair test because the only thing that is changed is the drop
During the immersion of the magnesium metal in the hydrochloric acid solution, white bubbles could be seen escaping the surface of the metal as gas was produced during the reaction. Depending on the temperature of the hydrochloric acid and the overall molar concentration, the rate of reaction differed but the same signs were shown. During the reaction between the magnesium metal and higher concentrations of hydrochloric acid, it was observed that the test tube grew quite warm to the touch. As the immersed magnesium strip sank down, it appeared coated in a layer of white bubbles that fizzed like a carbonated drink. In the lower concentrations of hydrochloric acid, the strip spent some time floating at the surface of the solution in the test tube, later sinking down to the bottom as the
At the end of the experiment when the lid was removed, it was found out that the blue colour of the copper (II) sulphate solution has faded away. It was turned to pale grey and there were some precipitates present. It was the zinc powder that was in excess to ensure that the copper (II) sulphate solution could react fully with the zinc powder.
Product bubbled upon addition to the hydrochloric acid; liquid turned cloudy ¡V precipitate was present; zinc sample disintegrated slowly and turned black in color.
To tube 3 a piece of litmus paper was placed into the tube. Then as is tube 2 concentrated HCl was added drop wise until the litmus paper indicated that it is acidic. No CO2 gas will evolve.
The control experiment for this investigation will be the experimental setup of 5 trials using 5oC as the temperature. All the steps in the method will be followed.
was too fast to measure and so for my scale to reach above that, I