• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

# Which equation is correct?

Free essay example:

Which equation is correct?

Aim:

Copper has two oxides, Cu2O and CuO.

Copper carbonate, CuCO3, decomposes on heating to form one of these oxides and an equation can be written for each possible reaction:

Equation 1:   2CuCO3 (s)Cu2O(s) + 2CO2(g) + ½O2 (g)

Equation 2:   CuCO3 (s)                 CuO(s) + CO2 (g)

I must determine which equation is correct.

Introduction:

From the two equations we can see when copper carbonate is heated or decomposed gases are given off. To find which equation is correct we can use ideas about moles, plan and design an experiment to measure a volume of gas that will prove which of the two equations is correct.

Therefore to find out the correct equation I will need to decompose the copper carbonate by heating and after this I will measure the amount of gas produced. The volume of gas will help me determine which equation is correct.

• It is possible to determine which equation is correct by measuring the volume of gas given off by the decomposition.

Measuring the volume of gas will tell me which equation is correct from above. I will need to measure the mass of copper carbonate as this will tell me the amount of copper carbonate needed in grams for the experiment and if it is correct it will show me what equation is correct. Also the volume of gas given off depends upon the molar quantities.

Equation 1:   2CuCO3 (s)Cu2O(s) + 2CO2(g) + 1\  2 O2 (g)

Equation 2:   CuCO3 (s)                 CuO(s) + CO2 (g)

Equation 2:

Gas used in experiment -30cm³

1 mole of any gas occupies 24000cm³

Therefore, the first thing I will need to do is find the moles. This is because the moles of copper carbonate are required to produce 30cm³ of gas.

Gas used in experiment30

The amount of which 1                     24,000           =1.25× 10 ֿ³ mole

mole of any gas occupies

Now that I have got the amount of moles the next step is to find the mass of copper carbonate. To do this I will need to multiply the moles and the RMM of copper carbonate.

The relative molecular mass of copper carbonate (CuCO3 ) is 123.50

I got this by adding copper, carbon and oxygen together. These were 63.50 for Cu, 12 for C and 48 for 3 oxygen’s.

Mass of  CuCO3                                               = moles × RMM

= 1.25× 10 ֿ³ × 123.5

= 0.154

Rounded to 2 decimal places            = 0.15 (weight in grams of copper carbonate)

This now shows me that I need 0.15 grams of copper carbonate.

Therefore this shows that if I have 0.15 grams of copper carbonate, it will release and produce 30cm³ of gas if equation 2 is correct.

Equation 1:

2 moles of CuCO3 =2 and a half moles of gas

This is telling me that 2 moles of copper carbonate will produce 2 and a half moles of gas.

Since one mole of copper carbonate is 1.25× 10 ֿ³ and equation 1 shows us it has 2 moles of copper carbonate I will need to divide 2.5(total amount if gas produced in equation 1) by 2.

1.25× 10 ֿ³ moles = 2 and a half   × 1.25× 10 ֿ³ moles

2

=1.5625× 10 ֿ³ mole

=1.56× 10 ֿ³ moles of gas

I will be now calculating the amount of gas produced in equation 1, so I will be multiplying the mole by 1 mole of any gas which is 24000cm³.

Volume of gas = 1.56× 10 ֿ³   × 24000

=37.44

=37.4cm³

Therefore the volume of gas for equation 1 is 37.4cm³. Also if I used 0.26 grams of copper carbonate, it will release and produce 37.4cm³ of gas.

Apparatus

• Copper carbonate, CuCO3
• Heatproof mat
• Safety goggles
• Bunsen burner
• Spatula
• Electric balance/Digital weighting scale
• 50cm3 Gas burette
• Boiling tube
• Beaker
• Rubber bung
• Delivery tube
• Lab coat
• Bottle of distilled water

Risk Assessment

 Chemical/Equipment Hazard Precaution Action in case of accident Copper Carbonate Irritant Wear a lab coat and for eye protection wear goggles, also keep away from skin contact. Wash thoroughly with running tap water. Bunsen burner Burning/scorching Keep burner on yellow flame when not in use. Cool part with running tap water. Report to teacher if serious. Glassware Can cause injury when broken Handle with care. Report to teacher in case of injury. Digital weighing scale/Balance Electric shock and falling over plug wires Make sure plug wires are safe were people cant fall over. Keep away from water. Report to teacher if serious.

Method/Procedure

1. First of all weigh 0.26grams CuCO3   and place it directly in the boiling tube.
2. Then I will fill roughly 50 ml of water into the gas burette to the top.
3. After this I will put my finger or thumb on top of the gas burette and turn it upside down into a beaker and uncover beneath the water surface. The beaker will also be filled with water. When placing the gas burette in the beaker which is full of water I have to make sure no water is lost otherwise it can have an affect on the experiment.
4. Then I will need to place a one holed rubber bung on the test tube. Inside the hole I will enter the tubing.
5. After all this I will need to get a bunsen burner and heat the copper carbonate.
6. The gas burette will start to collect bubbles and every time this happens water will be lost and the gas will come out on top of the gas burette.
7.  The rate of gas release will begin to slow down when decomposition is near completion. When the bubbling stops, remove the heat and the delivery tube at the same time.
8. Finally read the gas burette to determine the amount of water displaced by the gas. I will also need to record the room temperature which is likely to be between 20 and 24 degrees Celsius.

(http://www.cci.unl.edu/Chemistry/MicroScale/MScale16.html)

Image/Diagram The gas burette will be positioned with the help of a clamp.

The volume measured may need to be corrected because there can be the leakage of gas. I cannot be certain that there will be no leakage of gas therefore some gas can escape. The gas burette is not totally accurate and there maybe some human error such as when the gas burette is being read for its measurement. The weight of the copper carbonate measured may not be totally accurate and this can have an affect on the experiment or the volume of gas produced.

I am going to use a 50 cm3gas burette to collect the gas for the reason that a gas burette is more accurate and more reliable than a gas syringe and a measuring cylinder. The gas syringe is not reliable since it can get stuck and this will have a huge impact on the experiment. The measuring cylinder also has a disadvantage which is the accuracy of the readings are not correct or precise enough. Therefore I decided to use a gas burette since it is more accurate and more reliable than a gas syringe and a measuring cylinder.

Bibliography:

Website:

1. http://www.cci.unl.edu/Chemistry/MicroScale/MScale16.html

Books/Notes:

1. School sheets-Plan
2. Cambridge advanced sciences –chemistry 1-OCR___Page 71
3. Classroom notes

This student written piece of work is one of many that can be found in our AS and A Level War Poetry section. Not the one? Search for your essay title...
• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month

## Related AS and A Level English Skills and Knowledge Essays

Close
1. ## The aim of this experiment is to prove which of these two equations is ...

Word count: 1158

2. ## Right equation

Word count: 2171

3. ## The Decomposition of Copper Carbonate

Word count: 1091

4. ## determine the correct equation

Word count: 864

5. ## This experiment involves the decomposition of copper carbonate whereby we want to find out ...

Word count: 1210

6.  ## The idea of the experiment is to determine which equation is correct. There are ...

5 star(s)

Word count: 1517

7. ## I need to produce a marketing strategy for a new or existing product. I ...

Word count: 7323

8. ## Determination of the Value of the Gas Constant and the Molar Volume of Oxygen ...

Word count: 2671

# Related AS and A Level War Poetry essays

1.  ## The idea of the experiment is to determine which equation is correct. There are ...

5 star(s)

If the gas is CO2 then the gas will turn limewater milky. Prediction: I predict that equation 2 is correct. C2uCO3 CuO(s) + CO2(g) , because after I heated the salt, the residue was black in colour, confirming the presence of CuO.

2. ## Determination of the Value of the Gas Constant and the Molar Volume of Oxygen ...

gravity may effect level of gas in syringe Random - no method of controlling this factor * Syringe may have jammed or experienced friction - thus increasing the pressure the incoming gas was under; may have been held/influenced by wire safety string coiled about plunger Random - no method of

1. ## This experiment involves the decomposition of copper carbonate whereby we want to find out ...

Accuracy of Equipment and Reagents * All my results have been given to 3 significant figures except for the mass of copper carbonate, which is given to 2 decimal places because the scale can only measure to 2.d.p. Graduated Gas Syringe, Mass and Range: Equation 1 - 2CuCO3(s) Cu2O(s)

2. ## determine the correct equation

Method 1. Attach the gas syringe to the clamp stand making sure it is parallel to the bench as shown in the diagram. Press on the end of the gas syringe until the gas syringe reads 0ml of gas. 2.

1. ## The Decomposition of Copper Carbonate

However, in eqn1 O2 is also produced. The test for the presence of O2 is to place a glowing splint into the gas. If it relights, O2 is present. However, this method is not very adequate as the amount of O2 produced is very small in comparison to the CO2,

2. ## Right equation

If Copper carbonate form, Cu+ or Cu2+ and CO3- it created an ionic bond. Ionic bonding is when electrons are transferring electrons to another atom to form oppositely charged particles called ions which attract each other. [Cu (NH3)4(H2O)2]. Copper lies in periods 4, d-block in the periodic table.

1. ## The aim of this experiment is to prove which of these two equations is ...

equation is "stoichiometric"***, meaning that exactly one mole of copper carbonate decomposes to exactly one mole of copper oxide and exactly one mole of carbon dioxide. So: CuCO3 (s) --> CuO (s) + CO2 (g) 1mol 1mol 1mol And because 1 mole of any gas occupies 24dm� or 24000cm�: CuCO3 (s)

2. ## I need to produce a marketing strategy for a new or existing product. I ...

Their are adding further CRM capability, creating an on-line, real-time view of the individual customer - a powerful tool for call center agents, sales force and gas engineers. They will know the value of any customer at any point of interaction, and can target offers & service accordingly. • Over 160,000 pieces
of student written work
• Annotated by
experienced teachers
• Ideas and feedback to
improve your own work 