Describe what happens when copper fillings are added into a test tube of dilute hydrochloric acid.
When copper fillings are added into a test tube of dilute hydrochloric acid, a chemical reaction takes place. The reaction between copper and hydrochloric acid can be represented by the following balanced equation:
Cu (copper) + 2HCl (hydrochloric acid) → CuCl2 (copper chloride) + H2 (hydrogen gas)
As the copper fillings are added to the acid, they start to react with the hydrogen ions (H+) from the hydrochloric acid. This reaction results in the formation of copper chloride (CuCl2) and the release of hydrogen gas (H2) as a byproduct.
The reaction proceeds as the copper ions (Cu2+) from copper fillings combine with the chloride ions (Cl-) from the hydrochloric acid, forming copper chloride. The copper chloride may dissolve in the solution or precipitate, depending on the concentration of the resulting solution and the temperature.
Simultaneously, the hydrogen ions from the hydrochloric acid react with the copper fillings to produce hydrogen gas. This gas can be observed as small bubbles forming and rising to the surface of the test tube.
Overall, when copper fillings are added to dilute hydrochloric acid, the copper reacts with the acid, forming copper chloride, and hydrogen gas is released. The color of the solution may change due to the formation of copper chloride, and bubbles of hydrogen gas can be seen being released from the reaction mixture.
what happens when some copper fillings are added into a test tube of dilute nitric acid in a fume hood?
When copper fillings are added to a test tube of dilute nitric acid in a fume hood, a different chemical reaction occurs compared to when they are added to hydrochloric acid. The reaction between copper and nitric acid can be represented by the following balanced equation:
Cu (copper) + 4HNO3 (nitric acid) → Cu(NO3)2 (copper nitrate) + 2NO2 (nitrogen dioxide) + 2H2O (water)
In this reaction, the copper reacts with the nitric acid to form copper nitrate (Cu(NO3)2), nitrogen dioxide (NO2), and water (H2O) as byproducts.
When the copper fillings are added to the dilute nitric acid, the nitrogen and oxygen atoms from the nitric acid molecules oxidize the copper. This results in the formation of copper nitrate, which can dissolve in the solution. Additionally, nitrogen dioxide gas is produced, which is observed as reddish-brown fumes filling the fume hood.
It is important to perform this reaction in a fume hood to ensure the safe disposal of the toxic nitrogen dioxide gas produced. Nitrogen dioxide can be harmful if inhaled, so the fume hood allows for its controlled release without causing harm to the experimenter.
Overall, adding copper fillings to a test tube of dilute nitric acid in a fume hood results in the formation of copper nitrate, the release of nitrogen dioxide gas, and water. The fume hood is necessary to prevent the harmful fumes from spreading into the laboratory and to ensure the safety of those conducting the experiment.
When copper fillings are added into a test tube of dilute hydrochloric acid, several chemical reactions occur. Here is a step-by-step description of what happens:
Step 1: Initially, the copper fillings react with the hydrochloric acid to produce copper chloride and hydrogen gas. The chemical equation for this reaction can be represented as follows:
Cu (s) + 2HCl (aq) → CuCl2 (aq) + H2 (g)
Step 2: As the reaction proceeds, the copper fillings start to dissolve in the hydrochloric acid solution, forming a blue-green solution of copper chloride. This dissolution of copper in the acid is facilitated by the displacement of hydrogen from the acid by copper.
Step 3: Simultaneously, hydrogen gas is released as a product of the reaction. The gas bubbles can be observed escaping from the solution and rising to the top of the test tube. This effervescence is a visual indication that a gas is being produced.
Step 4: The reaction continues until either all the copper fillings have dissolved, or the acid is completely consumed. If excess copper fillings are present, the reaction will continue until all the acid is used up.
Overall, the addition of copper fillings to dilute hydrochloric acid results in the formation of copper chloride and the release of hydrogen gas. The blue-green color of the solution and the effervescence of gas bubbles are observable changes that suggest a chemical reaction is taking place.