How many milliliters of a 3.00 M solution of hydrochloric acid are needed to completely react with 25.0 g of zinc sulfide according to the chemical reaction shown below?
ZnS(s) + 2HCl(aq) ? ZnCl2(aq) + H2S(l)
(Answer to three significant digits.)
_____ mL of 3.00 M hydrochloric acid
You have the balanced equation.
Follow the instructions at this link to convert 25.0g ZnS to moles HCl.
Then M HCl = moles HCl/L HCl, solve for L HCl and convert to mL.
http://www.jiskha.com/science/chemistry/stoichiometry.html
To find the number of milliliters (mL) of a 3.00 M solution of hydrochloric acid needed to completely react with 25.0 g of zinc sulfide, we need to use stoichiometry.
Step 1: Convert the mass of zinc sulfide to moles
We need to find the number of moles of zinc sulfide. To do this, we can use the molar mass of zinc sulfide (ZnS). The molar mass of zinc (Zn) is 65.38 g/mol, and the molar mass of sulfur (S) is 32.06 g/mol.
Molar mass of ZnS = (1 * Molar mass of Zn) + (1 * Molar mass of S)
Molar mass of ZnS = (1 * 65.38 g/mol) + (1 * 32.06 g/mol)
Molar mass of ZnS = 97.44 g/mol
Now we can convert the mass of ZnS to moles using the formula:
moles of ZnS = mass of ZnS / molar mass of ZnS
moles of ZnS = 25.0 g / 97.44 g/mol
moles of ZnS ≈ 0.257 mol (to three significant digits)
Step 2: Determine the stoichiometric ratio of the reaction
From the balanced equation, we can see that the stoichiometric ratio between ZnS and HCl is 1:2. This means that 1 mole of ZnS reacts with 2 moles of HCl.
Step 3: Calculate the moles of HCl
Since the stoichiometric ratio is 1:2, the number of moles of HCl required is twice the number of moles of ZnS.
moles of HCl = 2 * moles of ZnS
moles of HCl = 2 * 0.257 mol
moles of HCl ≈ 0.514 mol (to three significant digits)
Step 4: Convert moles of HCl to milliliters of 3.00 M HCl
To convert moles of HCl to milliliters of 3.00 M HCl, we can use the definition of molarity, which is the number of moles of solute per liter of solution.
Molarity (M) = moles of solute / volume of solution (in liters)
We want to find the volume of solution in milliliters, so we need to rearrange the equation:
volume of solution (in mL) = (moles of solute / Molarity) * 1000
volume of solution (in mL) = (0.514 mol / 3.00 mol/L) * 1000
volume of solution ≈ 171 mL (to three significant digits)
Therefore, approximately 171 mL of a 3.00 M solution of hydrochloric acid are needed to completely react with 25.0 g of zinc sulfide.