How Much Copper Can Be Obtained from 100g of CuSO4
Copper sulfate (CuSO₄) is one of the most common copper salts and is widely used in various industries such as agriculture, electroplating, and in the synthesis of other copper compounds. Understanding how copper is extracted from copper sulfate is an essential topic in chemistry, especially when considering processes like displacement reactions or electrolysis.
In this article, we will explore the process of extracting copper from copper sulfate (CuSO₄), the stoichiometric calculations involved, and the amount of copper that can be obtained from a given mass of CuSO₄. The specific question we will address is: How much copper can be obtained from 100 grams of CuSO₄? To answer this, we will dive into the details of the molecular composition of CuSO₄, the chemical reactions involved, and the steps to calculate the theoretical yield of copper.
What is Copper Sulfate (CuSO₄)?
Copper sulfate is an inorganic compound with the chemical formula CuSO₄. It is a blue crystalline solid, also known as blue vitriol or bluestone. Copper sulfate is soluble in water and is often encountered in its pentahydrate form (CuSO₄·5H₂O), where it contains five molecules of water. The anhydrous form, CuSO₄, is used primarily in industrial and laboratory settings.
Key Properties of Copper Sulfate:
- Appearance: CuSO₄ in its anhydrous form is white, while the pentahydrate is blue.
- Solubility: Copper sulfate dissolves well in water, forming a blue solution.
- Uses: Copper sulfate is used in agriculture as a fungicide, in electroplating for copper deposition, and in chemical laboratories for various reactions.
When copper sulfate undergoes certain chemical reactions, especially in displacement reactions or electrolysis, copper metal can be extracted. The primary focus of this article is on how much copper can be obtained from CuSO₄ in a typical chemical reaction.
The Chemical Composition of Copper Sulfate
Copper sulfate consists of copper ions (Cu²⁺) and sulfate ions (SO₄²⁻). In a typical situation, such as a displacement reaction or electrolysis, the copper ions (Cu²⁺) are reduced to form copper metal (Cu), which is solid and can be separated.
The molar mass of CuSO₄ is calculated by adding the atomic masses of copper (Cu), sulfur (S), and oxygen (O):
- Copper (Cu) = 63.5 g/mol
- Sulfur (S) = 32.1 g/mol
- Oxygen (O) = 16.0 g/mol (and there are four oxygen atoms)
So, the molar mass of CuSO₄ is: 63.5+32.1+(4×16.0)=159.5 g/mol63.5 + 32.1 + (4 \times 16.0) = 159.5 \, \text{g/mol}
This means that one mole of copper sulfate weighs 159.5 grams.
Copper Extraction: The Displacement Reaction
One of the common ways to extract copper from copper sulfate is through a displacement reaction. In this reaction, a more reactive metal displaces copper from its compound. For example, if a piece of zinc metal (Zn) is placed in a solution of copper sulfate (CuSO₄), the zinc displaces the copper ions, producing copper metal.
The displacement reaction can be represented as follows: Zn (s)+CuSO₄ (aq)→ZnSO₄ (aq)+Cu (s)\text{Zn (s)} + \text{CuSO₄ (aq)} \rightarrow \text{ZnSO₄ (aq)} + \text{Cu (s)}
In this reaction:
- Zinc (Zn) displaces copper (Cu) from copper sulfate (CuSO₄), forming zinc sulfate (ZnSO₄) and copper metal.
- Copper ions (Cu²⁺) are reduced to form solid copper (Cu).
This reaction shows how copper metal is obtained from copper sulfate by using zinc. Now, let’s calculate how much copper can be obtained from 100g of copper sulfate (CuSO₄).
Stoichiometric Calculation: How Much Copper Can Be Obtained from 100g of CuSO₄?
To calculate the amount of copper that can be obtained from 100 grams of copper sulfate, we need to follow a series of steps involving molar mass, mole ratios, and the stoichiometry of the reaction.
Step 1: Calculate Moles of CuSO₄ in 100g
The molar mass of copper sulfate (CuSO₄) is 159.5 g/mol, as calculated earlier. To determine the number of moles of CuSO₄ in 100 grams, we use the formula: moles of CuSO₄=mass of CuSO₄molar mass of CuSO₄\text{moles of CuSO₄} = \frac{\text{mass of CuSO₄}}{\text{molar mass of CuSO₄}}
Substitute the values: moles of CuSO₄=100 g159.5 g/mol=0.626 mol\text{moles of CuSO₄} = \frac{100 \, \text{g}}{159.5 \, \text{g/mol}} = 0.626 \, \text{mol}
Step 2: Use the Mole Ratio to Find Moles of Copper (Cu)
From the balanced chemical equation: Zn (s)+CuSO₄ (aq)→ZnSO₄ (aq)+Cu (s)\text{Zn (s)} + \text{CuSO₄ (aq)} \rightarrow \text{ZnSO₄ (aq)} + \text{Cu (s)}
We can see that 1 mole of CuSO₄ produces 1 mole of Cu. Therefore, the number of moles of copper obtained will be the same as the number of moles of copper sulfate.
Thus, the moles of copper (Cu) produced from 0.626 moles of CuSO₄ is also 0.626 moles.
Step 3: Calculate the Mass of Copper (Cu)
Now, we need to calculate the mass of copper produced from 0.626 moles. The molar mass of copper is 63.5 g/mol. We can use the formula: mass of Cu=moles of Cu×molar mass of Cu\text{mass of Cu} = \text{moles of Cu} \times \text{molar mass of Cu}
Substitute the values: mass of Cu=0.626 mol×63.5 g/mol=39.7 g\text{mass of Cu} = 0.626 \, \text{mol} \times 63.5 \, \text{g/mol} = 39.7 \, \text{g}
Final Answer:
From 100 grams of copper sulfate (CuSO₄), approximately 39.7 grams of copper (Cu) can be obtained through a displacement reaction.
Practical Considerations in Copper Extraction
While stoichiometric calculations give us an ideal theoretical yield, in practice, the amount of copper that can be extracted may be less than the theoretical amount due to several factors:
- Purity of Copper Sulfate: In real-world situations, the copper sulfate used may not be pure. Impurities can reduce the efficiency of the reaction, leading to a lower yield of copper.
- Reaction Efficiency: In displacement reactions, the efficiency of metal displacement may vary depending on factors such as temperature, concentration of the copper sulfate solution, and the surface area of the zinc metal.
- Side Reactions: Other side reactions, such as the formation of secondary compounds, might occur, affecting the amount of copper extracted.
- Environmental Conditions: External factors such as the presence of air or moisture could influence the reaction dynamics, leading to a reduced yield.
Other Methods of Extracting Copper from CuSO₄
Apart from displacement reactions, copper can also be extracted from copper sulfate through electrolysis. In the electrolysis process, a copper sulfate solution is used as the electrolyte, and an electric current is passed through the solution. Copper ions are reduced at the cathode, and copper metal is deposited.
Electrolysis Process:
- Anode: Copper from the anode is oxidized to Cu²⁺ ions and enters the solution.
- Cathode: Copper ions (Cu²⁺) from the solution are reduced and deposited as solid copper.
Electrolysis allows for the extraction of copper with high purity and is used in industrial applications such as copper refining.
Conclusion
In conclusion, approximately 39.7 grams of copper can be obtained from 100 grams of copper sulfate (CuSO₄) through a displacement reaction with a more reactive metal like zinc. The stoichiometric calculation, based on the molar masses of CuSO₄ and copper, shows that the copper extracted is directly related to the amount of copper sulfate used.
While this is the theoretical amount, practical factors such as reaction efficiency, purity of the materials, and experimental conditions may lead to variations in the actual yield. Regardless, the concept of stoichiometry provides a fundamental method to calculate the yield of copper from copper sulfate, whether in academic exercises or industrial applications.
