8-hydroxyquinoline (Q) can complex and precipitate many metals. A mixture of the aluminium and magnesium complexes weighed 1.0843g (MW=459.43; 312.61). When ignited, the mixture decomposed and left a residue of Al203 (MW 101.96) and MgO (MW 40.304) weighing 0.1344g. What is the weight percentage of the Al-complex in the mixture?

To be really honest, i don't have a single idea of how to start.
Should i calculate the no. of moles of Al2O3 and MgO and then assume it to be that of the Al complex and then find the mass of Al complex.

And finally use wt%=(mass Al complex)/(1.0843) * 100

Please guide me, im totally confused

This is a two equation and solve simultaneously. Al reacts with 8-hydroxyqinoline (Q) to form Alq3. Mg reacts similarly to form Mgq2.

Let X = weight Alq3
and Y = weight Mgq2, then
--------------------
equation 1 is X + Y = 1.0843

The second equation is obtained from the Al2O3 residue.[MM stands for molar mass.]
Convert grams X to grams Al2O3 which will be
X*(MM Al2O3/2*MM Alq3)
Convert grams Y to grams MgO. That will be
Y*(MM MgO/MM Mgq2). When you add the Al2O3 and MgO you end up with 0.1344 g. so equation 2 is
X*(MM Al2O3/2*MM Alq3) + Y*(MM MgO/MM Mgq2) = 0.1344.

Solve for X and Y simultaneously, then
%Alq3 = (mass Alq3/1.0843)*100 = ?
I have for formula of Alq3 = Al(C9H6NO)3 and Mgq2 is Mg(C9H6NO)2

Ah, chemistry, the art of turning confusion into clarity! Don't worry, my friend, I'm here to guide you through this with a touch of humor. Let's tackle it step by step:

1. Start by finding the moles of Al2O3 and MgO in the residue: You're absolutely right! Calculate the moles of Al2O3 and MgO using their respective molecular weights and the given mass. I believe in you!

2. Assuming all the Al2O3 and MgO came from the respective complexes, you can now find the moles of Al and Mg: Al2O3 will give you moles of Al, and MgO will give you moles of Mg. Easy, right?

3. The molar ratio between Al and the Al-complex will help you calculate the moles of the Al-complex: Use the balanced equation of the reaction between Al-complex and Al2O3 to figure out this ratio. Remember, chemistry is all about ratios, like cookies to happiness!

4. Now determine the moles (and thus the mass) of the Al-complex in the initial mixture: Use the moles of Al and the molar ratio you just found to calculate the moles and mass of the Al-complex present initially.

5. Finally, calculate the weight percentage of the Al-complex: Divide the mass of the Al-complex by the initial mass of the mixture (from the given weight), and multiply by 100. Voila! You've got your answer!

Remember, chemistry can be intimidating, but taking it step by step makes it much more manageable. So go ahead, my friend, put on your chemistry goggles and make those calculations dance like a performing clown!

To solve this problem, we can follow the steps you mentioned. Let's go through the solution step by step:

Step 1: Determine the moles of Al2O3 and MgO:
- Given the weight of Al2O3 and MgO residue: 0.1344g
- Calculate the number of moles of Al2O3: moles = mass / molar mass = 0.1344g / 101.96g/mol = 0.001317 moles
- Calculate the number of moles of MgO: moles = mass / molar mass = 0.1344g / 40.304g/mol = 0.003335 moles

Step 2: Calculate the moles of the complexes:
- Given the weight of the mixture of Al and Mg complexes: 1.0843g
- Subtract the weight of the residue (Al2O3 and MgO): 1.0843g - 0.1344g = 0.9499g
- Calculate the total moles in the mixture: moles = mass / molar mass = 0.9499g / (459.43g/mol + 312.61g/mol) = 0.001765 moles

Step 3: Determine the weight of the Al complex:
- Recall that the weight of the Al complex is equal to the weight of the mixture minus the weight of the residue: 0.9499g - 0.1344g = 0.8155g

Step 4: Calculate the weight percentage of the Al complex in the mixture:
- Calculate the weight percentage: weight percentage = (mass of Al complex / mass of mixture) * 100 = (0.8155g / 1.0843g) * 100 = 75.3%

So, the weight percentage of the Al complex in the mixture is 75.3%.

To solve this problem, we can follow these steps:

Step 1: Start by calculating the number of moles of Al2O3 and MgO in the residue.

Number of moles of Al2O3 = mass of Al2O3 / molar mass of Al2O3
Number of moles of MgO = mass of MgO / molar mass of MgO

Using the given values:
Number of moles of Al2O3 = 0.1344g / 101.96 g/mol
Number of moles of MgO = 0.1344g / 40.304 g/mol

Step 2: Since the mixture consists of both Al and Mg complexes, we can assume that the number of moles of Al complex is equal to the number of moles of Al2O3.

Number of moles of Al complex = Number of moles of Al2O3

Step 3: Use the molar mass of Al complex to convert the number of moles to grams.

Mass of Al complex = Number of moles of Al complex * molar mass of Al complex

Step 4: Calculate the weight percentage of the Al complex in the mixture.

Weight percentage of Al complex = (Mass of Al complex / 1.0843g) * 100

Plug in the values and perform the calculations to find the weight percentage of the Al complex in the mixture.

I hope this helps! Let me know if you have any further questions.