Do ions combine in definite ratios
- Pages: 3
- Word count: 551
- Category: Chemistry
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1.The reaction that occurred in the experiment was a chemical reaction, double displacement-precipitate reaction. The Copper reacted with the carbonate and form the precipitate, while the Sodium and Sulfate was the ?clear? part in the test tube.
CuSO4 (aq) + NaCO3 (aq) à CuCo3(s) + NaSO4 (aq)
2.Refer to table 1.2
3.The test tube that contains the most precipitate is #3. This one has the most because of the ratio of Cu to CO3 ions (1:1); therefore the Copper can react equally with the carbonate and the Sodium with the Sulfate. I can conclude then that the close the ratio is the more precipitate will be present.
4.Test tubes #1 and #5 contain the least precipitate because the ratios are the largest, (1:9 , 9:1). Both test tubes produced the same amount of precipitate though. Since the ratios are large that means that one chemical will only have a small amount to react with the other chemical. I can establish that opposite ratios will have the same amount of precipitate.
5.This evidence suggests that ions combine in definite proportions because whenever a large amount of the copper (II) sulfate was added to a smaller amount of the sodium carbonate a small amount of precipitate was produced. Also whenever a small amount of copper (II) sulfate was added to a larger amount of sodium carbonate, still a small amount of precipitate was formed. Therefore ?
Furthermore ions do combine in definite ratios because of the valance electrons. Each chemical has a certain amount of valence electrons, so when another chemical comes to form a molecular bond it must occupy the remaining area of the shell to become stable. No matter what the chemical will always have the same amount of valence electrons, as a result always combining in definite proportions.
Therefore by adding the appropriate amounts of copper (II) sulfate and sodium carbonate together a chemical reaction occurred and a precipitate was formed. The precipitate was the CuCo3(s) and was formed at the bottom of the test tube while the clear ?liquid? was the NaSO4 (aq) , which formed at the top. A double displacement occurred, CuSO4 (aq) + NaCO3 (aq) à CuCo3(s) + NaSO4 (aq).
Through table 1.1 and 1.2 several distinct patterns are shown. The test tubes with opposite ratios (ex: Test tube 1 and test tube 5) have the same amount of precipitate and colour because there is only so much of one substance that can react with the other. Therefore test tube 3, which had a ratio of 1:1 had the most precipitate, in view of the fact that there was an equal amount of each substance that could react with each other. The closer the ratio, the more precipitate. In addition the test tubes with the larger ratios were found to have a light colour of blue, while the test tubes with the smaller ratios achieved a darker blue.
The hypothesis was correct in saying that the ions would combine in definite ratios even though the experiment did not prove that it did due to the valence electrons. The ?valence electron theory? is the theoretical explanation in which in cannot be observed.
For those reasons one can conclude that ions do combine in definite ratios.