What mass of sulfuric acid, H2SO4, is required to react with 1.27 g of potassium hydroxide, KOH? The products of this reaction are potassium sulfate
and water.
Have both the unbalanced and balanced chemical equations.
Explain how to find the molar mass of the compounds.
Explain how the balanced chemical equation is used to find the ratio of moles (hint: step 3 in the video).
Explain how many significant figures your answer needs to have.
The numerical answer
H2SO4 + 2KOH ==? K2SO4 + 2H2O
mols KOH = grams/molar mass = 1.27/56.1 = 0.0226
Convert mols KOH to mols H2SO4 using the coefficients in the balanced equation. 0.0226 mols KOH x (1 mol H2SO4/2 mol KOH) = 0.0226 x 1/2 = 0.0113.
Then grams H2SO4 = mols H2SO4 x molar mass H2SO4 = ?
There are three significant figures in1.27 so you are allowed 3 in the answer. I don't know about a video.
Why did the acid go to the gym? To get better at balancing equations!
Alright, let's get down to business. The unbalanced chemical equation for the reaction between sulfuric acid (H2SO4) and potassium hydroxide (KOH) is:
H2SO4 + KOH → K2SO4 + H2O
To find the molar mass of a compound, you need to add up the atomic masses of all the atoms in that compound. For example, for sulfuric acid (H2SO4), the molar mass would be:
(2 x atomic mass of hydrogen) + atomic mass of sulfur + (4 x atomic mass of oxygen)
Now, to balance the chemical equation, we want the same number of atoms on both sides. We start by balancing the atoms that appear in only one compound. In this case, we have potassium (K), sulfur (S), and hydrogen (H).
In the unbalanced equation, we have 1 potassium atom on the left (from KOH) but 2 potassium atoms on the right (from K2SO4). To balance them out, we put a 2 in front of KOH:
H2SO4 + 2KOH → K2SO4 + H2O
Next, we have 1 sulfur atom on the left but 1 sulfur atom on the right, so sulfur is already balanced.
Lastly, we have 2 hydrogen atoms on the left (from H2SO4) and 2 hydrogen atoms on the right (from H2O). Hydrogen is balanced as well.
Now we have a balanced chemical equation:
H2SO4 + 2KOH → K2SO4 + H2O
This balanced equation allows us to determine the mole ratio between the reactants and products. In this case, the mole ratio tells us that for every 1 mole of sulfuric acid, we need 2 moles of potassium hydroxide to produce 1 mole of potassium sulfate and 1 mole of water.
To find the mass of sulfuric acid required to react with 1.27 g of potassium hydroxide, we need to convert grams of potassium hydroxide to moles, using its molar mass. Then, we use the mole ratio from the balanced equation to determine the moles of sulfuric acid needed. Finally, we convert moles of sulfuric acid to grams, using its molar mass.
For the number of significant figures, you should use the same number of significant figures as the given mass of potassium hydroxide. In this case, it's 1.27 g, so your final answer should also have 3 significant figures.
Hope this chemistry clown act didn't leave you in acid reflux!
To solve this problem, we can follow these steps:
1. Write the unbalanced chemical equation for the reaction:
H2SO4 + KOH -> K2SO4 + H2O
2. Balance the chemical equation by ensuring that there are an equal number of atoms of each element on both sides of the equation:
H2SO4 + 2KOH -> K2SO4 + 2H2O
3. Find the molar masses of sulfuric acid (H2SO4) and potassium hydroxide (KOH).
- The molar mass of H2SO4 can be calculated by adding the atomic masses of each element:
H2 (2 hydrogen atoms) --> 2 x 1.01 g/mol = 2.02 g/mol
S (1 sulfur atom) --> 1 x 32.07 g/mol = 32.07 g/mol
O4 (4 oxygen atoms) --> 4 x 16.00 g/mol = 64.00 g/mol
Adding these masses gives: 2.02 g/mol + 32.07 g/mol + 64.00 g/mol = 98.09 g/mol
- The molar mass of KOH can be calculated in a similar way:
K (1 potassium atom) --> 1 x 39.10 g/mol = 39.10 g/mol
O (1 oxygen atom) --> 1 x 16.00 g/mol = 16.00 g/mol
H (1 hydrogen atom) --> 1 x 1.01 g/mol = 1.01 g/mol
Adding these masses gives: 39.10 g/mol + 16.00 g/mol + 1.01 g/mol = 56.11 g/mol
4. Use the balanced chemical equation to find the ratio of moles between the reactants.
From the balanced chemical equation: 1 mole of H2SO4 reacts with 2 moles of KOH to produce 1 mole of K2SO4 and 2 moles of H2O.
5. Convert the mass of KOH given in the question (1.27 g) to moles.
To do this, divide the given mass by the molar mass of KOH:
Moles of KOH = 1.27 g / 56.11 g/mol = 0.0226 mol
6. Use the ratio of moles from step 4 to determine the moles of H2SO4 required.
From the balanced chemical equation, we know that 1 mole of H2SO4 reacts with 2 moles of KOH.
Therefore, the moles of H2SO4 required = 0.0226 mol x (1 mol H2SO4 / 2 mol KOH) = 0.0113 mol
7. Finally, calculate the mass of H2SO4 required.
To do this, multiply the moles of H2SO4 by its molar mass:
Mass of H2SO4 = 0.0113 mol x 98.09 g/mol = 1.12 g
So, the mass of sulfuric acid (H2SO4) required to react with 1.27 g of potassium hydroxide (KOH) is 1.12 g.
Regarding significant figures: In this case, the given mass of KOH has three significant figures (1.27 g). Therefore, the final answer should also have three significant figures, giving a mass of H2SO4 required as 1.12 g.
To find the mass of sulfuric acid required to react with potassium hydroxide, we first need to write the chemical equation for the reaction.
Unbalanced chemical equation: H2SO4 + KOH → K2SO4 + H2O
To balance the equation, we need to ensure that both sides have an equal number of atoms of each element. Balancing the equation gives us:
2H2SO4 + 2KOH → K2SO4 + 2H2O
Now, let's move on to finding the molar mass of the compounds involved. The molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol).
To find the molar mass of a compound, we add up the atomic masses of all the elements present in the compound, considering their respective subscripts.
For sulfuric acid (H2SO4), we can calculate its molar mass as follows:
2(atomic mass of hydrogen, H) + atomic mass of sulfur, S + 4(atomic mass of oxygen, O)
2(1.008 g/mol) + 32.06 g/mol + 4(16.00 g/mol) = 98.09 g/mol
For potassium hydroxide (KOH), we can calculate its molar mass as follows:
atomic mass of potassium, K + atomic mass of oxygen, O + atomic mass of hydrogen, H
39.10 g/mol + 16.00 g/mol + 1.008 g/mol = 56.11 g/mol
With the balanced chemical equation in hand, we can now determine the ratio of moles between the reactants. From the balanced equation, we see that the stoichiometric ratio between sulfuric acid and potassium hydroxide is 2:2.
This means that for every 2 moles of sulfuric acid, we require 2 moles of potassium hydroxide for a complete reaction.
Now that we have the molar masses of the compounds and the stoichiometric ratio, we can calculate the mass of sulfuric acid required to react with 1.27 g of potassium hydroxide.
First, find the number of moles of potassium hydroxide:
moles of KOH = (mass of KOH) / (molar mass of KOH)
moles of KOH = 1.27 g / 56.11 g/mol ≈ 0.02266 mol
Now, since the stoichiometric ratio between sulfuric acid and potassium hydroxide is 2:2, we can infer that the number of moles of sulfuric acid required is also 0.02266 mol.
Finally, we can calculate the mass of sulfuric acid:
mass of H2SO4 = (moles of H2SO4) x (molar mass of H2SO4)
mass of H2SO4 = 0.02266 mol x 98.09 g/mol = 2.23 g (rounded to three significant figures)
Therefore, the mass of sulfuric acid required to react with 1.27 g of potassium hydroxide is approximately 2.23 g. The answer needs to have three significant figures to reflect the accuracy of the given mass of potassium hydroxide.