A sample of the compound prepared in this experiment, weighing .1021g, is dissolved in HNO3 and diluted to a volume of 100mL. A 10mL aliquot of that solution is mixed iwth 10mL 6 M NH3. The [Cu(NH3)4 2+] in the resulting solution is 5.16x10^-3 M.
How many moles of Cu were in the original sample, which had been effectively diluted to a volume of 200mL?
How many grams of Cu were in the sample?
How many grams of Cl were in the sample? How many moles?
What is the formula of the Copper Chloride compound?
Something is missing and I don't know what it is. moles Cu = moles of the Cu ammine complex x L; but I don't know where the 200 mL comes from.
grams = moles x atomic mass
I have no idea about grams Cl.
or moles Cl
or the formula.
To answer these questions, we need to understand the chemical reactions involved and calculate the relevant quantities. Let's break it down step by step.
1. Calculate the moles of Cu in the original sample:
Given:
- The molar concentration of [Cu(NH3)4 2+] in the resulting solution: 5.16x10^-3 M.
- The volume of the aliquot taken for mixing: 10 mL.
- The total volume of the resulting solution obtained after mixing: 20 mL.
First, let's find the moles of [Cu(NH3)4 2+] in the resulting solution:
moles of [Cu(NH3)4 2+] = concentration × volume = 5.16x10^-3 M × 20 mL
However, we need to convert the volume from mL to liters:
20 mL = 20/1000 L = 0.02 L
Therefore, moles of [Cu(NH3)4 2+] = 5.16x10^-3 M × 0.02 L
Next, we need to consider the stoichiometry of the reaction:
[Cu(NH3)4 2+] + 4NH3 -> Cu(NH3)4 2+
From the balanced equation, we see that 1 mole of [Cu(NH3)4 2+] corresponds to 1 mole of Cu.
So, the moles of Cu in the original sample = moles of [Cu(NH3)4 2+] = 5.16x10^-3 M × 0.02 L
2. Calculate the grams of Cu in the sample:
To find the mass of Cu, we need to use its molar mass. The molar mass of Cu is approximately 63.55 g/mol.
grams of Cu = moles of Cu × molar mass of Cu
3. Calculate the grams and moles of Cl in the sample:
From the given information, we don't have direct data about the moles or grams of Cl in the sample, so we cannot calculate them. The composition of the compound and the quantity of Cl present are not provided.
Please provide additional information about the compound or its composition to determine the grams and moles of Cl.
4. Determine the formula of the Copper Chloride compound:
Since we don't have information about the composition, it is not possible to determine the formula of the Copper Chloride compound without additional data specifying the stoichiometry or composition.