10.5g of Zinc trioxocarbonate (iv),were heated very strongly to a constant mass and the residue treated with excess hydrochloric acid. Calculate the mass of Zinc chloride that would be obtained

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To calculate the mass of zinc chloride that would be obtained from the reaction, we need to understand the stoichiometry of the reaction between zinc trioxocarbonate (IV) and hydrochloric acid.

The balanced chemical equation for the reaction can be written as follows:

ZnCO3 + 2HCl → ZnCl2 + CO2 + H2O

From the balanced equation, we can see that 1 mole of zinc trioxocarbonate (IV) reacts with 2 moles of hydrochloric acid to produce 1 mole of zinc chloride.

To solve the problem, we need to follow these steps:

Step 1: Convert the given mass of zinc trioxocarbonate (IV) to moles.
To do this, we use the molar mass of ZnCO3, which is calculated by summing the atomic masses of zinc (Zn), carbon (C), and three oxygen (O) atoms.
The molar mass of ZnCO3 = (65.38 g/mol) + (12.01 g/mol) + (3 * 16.00 g/mol) = 125.38 g/mol

We can now compute the number of moles of ZnCO3 using the formula:
moles = mass / molar mass

moles of ZnCO3 = 10.5 g / 125.38 g/mol

Step 2: Use the stoichiometry of the balanced equation to calculate the moles of zinc chloride.
From the balanced equation, we know that the ratio of moles of ZnCO3 to ZnCl2 is 1:1.

moles of ZnCl2 = moles of ZnCO3

Step 3: Convert moles of zinc chloride to mass.
To do this, we need to know the molar mass of ZnCl2, which is calculated by summing the atomic masses of zinc (Zn) and two chlorine (Cl) atoms.
The molar mass of ZnCl2 = (65.38 g/mol) + (2 * (35.45 g/mol)) = 136.23 g/mol

mass of ZnCl2 = moles of ZnCl2 * molar mass of ZnCl2

Now, let's substitute the calculated values into the equation:

mass of ZnCl2 = moles of ZnCO3 * molar mass of ZnCl2

mass of ZnCl2 = (10.5 g / 125.38 g/mol) * 136.23 g/mol

By performing the above calculation, you will find the mass of zinc chloride obtained from the reaction.

Where did you get that name for ZnCO3? There is no such name. Zinc carbonate is one of the preferred names by IUPAC for ZnCO3. If you obtained that from a text please give me the reference. Please cite your source.

ZnCO3 + heat --> ZnO + CO2, then
ZnO + 2HCl ==> ZnCl2 +H2O
mols ZnCO3 = grams/molar mass = 10.5/? = about 0.08 but that's just a guess. You need to find a more accurate number.
Then 0.084 mols ZnCO3 x (1 mol ZnO/1 mol ZnCO3) x (1 mol ZnCl2/1 mol ZnO) = 0.084 mols ZnCl2.
mass ZnCl2 = mols ZnCl2 x molar mass ZnCl2
Post your work if you don't understand.