what volume of hydrochloric acid of density 1.18g cm3 and containing35.0% by mass must be allowed to react with zinc in order to liberate 6.36g H2 gas?
can you tell me the steps. i get so confused with this topic.
I don't know how you came up with a title of molality.
Here is a stoichiometry problem (that's this type) I've posted as an example. Just follow the steps.
http://www.jiskha.com/science/chemistry/stoichiometry.html
the molality possibly should have been molarity. i am getting the two confused at the moment. this is a revision question in my topic on solutions.
I call this a stoichiometry problem.
Sure! I can help you with that.
To find the volume of hydrochloric acid required, you'll need to follow a few steps:
Step 1: Convert the mass of hydrogen gas (H2) to moles.
You are given that 6.36g of H2 gas is liberated. To convert this mass to moles, you need to use the molar mass of hydrogen, which is 2.02 g/mol. Divide the mass of H2 by its molar mass:
moles of H2 = mass of H2 / molar mass of H2
moles of H2 = 6.36g / 2.02 g/mol
Step 2: Use stoichiometry.
The balanced chemical equation for the reaction between hydrochloric acid (HCl) and zinc (Zn) is:
Zn + 2HCl -> ZnCl2 + H2
From the equation, you can see that 1 mole of Zn reacts with 2 moles of HCl to produce 1 mole of H2 gas. This means that the moles of HCl needed can be calculated as:
moles of HCl = moles of H2 / 2
Step 3: Convert moles of HCl to grams.
Now, you need to convert the moles of HCl to grams using the molar mass of HCl, which is 36.46 g/mol.
mass of HCl = moles of HCl * molar mass of HCl
Step 4: Convert grams of HCl to volume.
Since the density of the hydrochloric acid is given (1.18 g/cm3), you can use the formula:
volume = mass / density
volume = mass of HCl / density of HCl
Substituting the value of mass of HCl calculated in step 3 and the given density of 1.18 g/cm3, you can calculate the volume of hydrochloric acid required.
Keep in mind that when performing calculations involving concentration or percentage by mass, it is important to clarify what those percentages represent (in this case, the percentage represents the mass of HCl in the hydrochloric acid solution).
I hope this step-by-step explanation helps you! Let me know if you have any further questions.