Balance Chemical Equation: H2SO4 + Al2(OH)3 Step-by-Step

by Chloe Fitzgerald 57 views

Hey guys! Balancing chemical equations can seem like a daunting task, but trust me, it's totally manageable once you break it down. In this guide, we're going to tackle a specific equation: H2SO4 + Al2(OH)3 → Al2(SO4)3 + H2O. This is a classic example that combines sulfuric acid (H2SO4) with aluminum hydroxide (Al2(OH)3) to produce aluminum sulfate (Al2(SO4)3) and water (H2O). We'll go through each step meticulously, so you'll not only understand the how but also the why behind balancing equations. So, grab your periodic table, and let's dive in!

Why Balancing Equations Matters

Before we jump into the nitty-gritty, let’s quickly chat about why balancing chemical equations is super important. Think of it like cooking – you need the right amount of each ingredient to get the perfect dish, right? Same with chemistry! A balanced equation ensures that you have the same number of atoms for each element on both sides of the reaction. This is based on the Law of Conservation of Mass, which basically states that matter can’t be created or destroyed in a chemical reaction. So, if you start with 2 aluminum atoms, you need to end with 2 aluminum atoms. No more, no less. Balancing equations helps us predict the amounts of reactants and products involved in a chemical reaction, which is crucial for everything from designing experiments to industrial processes. Trust me, understanding this principle is a game-changer in chemistry!

Breaking Down the Equation: H2SO4 + Al2(OH)3 → Al2(SO4)3 + H2O

Okay, let’s get to the equation at hand: H2SO4 + Al2(OH)3 → Al2(SO4)3 + H2O. This might look like a jumble of letters and numbers, but don’t sweat it. We're going to dissect it piece by piece. On the left side, we have our reactants: sulfuric acid (H2SO4) and aluminum hydroxide (Al2(OH)3). Sulfuric acid is a strong acid commonly used in various industrial processes, while aluminum hydroxide is often found in antacids. On the right side, we have our products: aluminum sulfate (Al2(SO4)3) and water (H2O). Aluminum sulfate has a bunch of applications, including water treatment and dyeing fabrics. Now, let's break down each compound into its elements. In H2SO4, we have hydrogen (H), sulfur (S), and oxygen (O). In Al2(OH)3, we have aluminum (Al), oxygen (O), and hydrogen (H). In Al2(SO4)3, we have aluminum (Al), sulfur (S), and oxygen (O). And finally, in H2O, we have hydrogen (H) and oxygen (O). Our mission is to make sure that the number of each of these atoms is the same on both sides of the equation. Are you ready to get started? Let's do this!

Step-by-Step Guide to Balancing

Alright, let’s get our hands dirty and dive into the actual balancing process. We're going to take it one step at a time, so you can follow along easily. Balancing chemical equations is like solving a puzzle, and each step is a piece of that puzzle. By the end of this, you'll be a pro at balancing this equation and many others!

Step 1: Identify the Elements

First things first, we need to identify all the elements present in our equation: H2SO4 + Al2(OH)3 → Al2(SO4)3 + H2O. As we discussed earlier, we have hydrogen (H), sulfur (S), aluminum (Al), and oxygen (O). Write these elements down in a list – this will help us keep track of everything. A neat list might look like this:

  • H
  • S
  • Al
  • O

This list is our roadmap for balancing the equation. Make sure you have each element clearly written down, because we'll be referring to this list throughout the process. Trust me, this simple step can save you a lot of headaches later on. With our elements identified, we're ready to move on to the next step: counting the atoms.

Step 2: Count the Atoms

Now that we know which elements are involved, let’s count how many atoms of each element are on both sides of the equation. This is where things get a bit more hands-on. For the reactants (left side) and products (right side), we'll count each atom individually.

  • Reactants (H2SO4 + Al2(OH)3):
    • Hydrogen (H): We have 2 in H2SO4 and 3 in Al2(OH)3, totaling 2 + 3 = 5
    • Sulfur (S): We have 1 in H2SO4
    • Aluminum (Al): We have 2 in Al2(OH)3
    • Oxygen (O): We have 4 in H2SO4 and 3 in Al2(OH)3, totaling 4 + 3 = 7
  • Products (Al2(SO4)3 + H2O):
    • Aluminum (Al): We have 2 in Al2(SO4)3
    • Sulfur (S): We have 3 in Al2(SO4)3
    • Oxygen (O): We have 12 in Al2(SO4)3 and 1 in H2O, totaling 12 + 1 = 13
    • Hydrogen (H): We have 2 in H2O

Let's summarize this in a table – it makes things super clear:

Element Reactants Products
H 5 2
S 1 3
Al 2 2
O 7 13

Looking at the table, we can see that hydrogen, sulfur, and oxygen are not balanced. Aluminum is balanced, which is a small win! Our next job is to adjust the coefficients to balance the remaining elements. Onward we go!

Step 3: Start Balancing (H and S)

Okay, time to roll up our sleeves and start balancing! We usually begin with elements other than hydrogen and oxygen because they often appear in multiple compounds, which can complicate things. In our case, let's start with sulfur (S) because it appears only once on each side of the equation, making it a straightforward element to balance first. Looking at our table, we have 1 sulfur atom on the reactant side (H2SO4) and 3 sulfur atoms on the product side (Al2(SO4)3). To balance sulfur, we need to add a coefficient of 3 in front of H2SO4:

3H2SO4 + Al2(OH)3 → Al2(SO4)3 + H2O

Now, let’s update our count. We’ve changed the number of sulfur atoms, and this also affects the number of hydrogen and oxygen atoms on the reactant side:

  • Reactants (3H2SO4 + Al2(OH)3):
    • Hydrogen (H): 3 * 2 (from H2SO4) + 3 (from Al2(OH)3) = 6 + 3 = 9
    • Sulfur (S): 3 * 1 (from H2SO4) = 3
    • Aluminum (Al): 2 (from Al2(OH)3)
    • Oxygen (O): 3 * 4 (from H2SO4) + 3 (from Al2(OH)3) = 12 + 3 = 15
  • Products (Al2(SO4)3 + H2O):
    • Aluminum (Al): 2 (from Al2(SO4)3)
    • Sulfur (S): 3 (from Al2(SO4)3)
    • Oxygen (O): 12 (from Al2(SO4)3) + 1 (from H2O) = 13
    • Hydrogen (H): 2 (from H2O)

Our updated table looks like this:

Element Reactants Products
H 9 2
S 3 3
Al 2 2
O 15 13

Sulfur is now balanced! Awesome! Now, let’s tackle hydrogen. We have 9 hydrogen atoms on the reactant side and only 2 on the product side. To balance hydrogen, we need to find a common multiple. What do you think we should do? Let's move to the next step and figure it out.

Step 4: Balancing Hydrogen (H)

Alright, let's tackle hydrogen next. We've got 9 hydrogen atoms on the reactant side (from 3H2SO4 and Al2(OH)3) and only 2 on the product side (from H2O). To balance these, we need to find the least common multiple of 9 and 2, which is 18. To get 18 hydrogen atoms on the reactant side, we already have 9, so that's good. On the product side, we need to multiply the 2 hydrogen atoms in H2O by 9 to get 18. So, we add a coefficient of 9 in front of H2O:

3H2SO4 + Al2(OH)3 → Al2(SO4)3 + 9H2O

Now, let’s update our count again:

  • Reactants (3H2SO4 + Al2(OH)3):
    • Hydrogen (H): 3 * 2 (from H2SO4) + 3 (from Al2(OH)3) = 6 + 3 = 9
    • Sulfur (S): 3 * 1 (from H2SO4) = 3
    • Aluminum (Al): 2 (from Al2(OH)3)
    • Oxygen (O): 3 * 4 (from H2SO4) + 3 (from Al2(OH)3) = 12 + 3 = 15
  • Products (Al2(SO4)3 + 9H2O):
    • Aluminum (Al): 2 (from Al2(SO4)3)
    • Sulfur (S): 3 (from Al2(SO4)3)
    • Oxygen (O): 12 (from Al2(SO4)3) + 9 * 1 (from 9H2O) = 12 + 9 = 21
    • Hydrogen (H): 9 * 2 (from 9H2O) = 18

Here’s our updated table:

Element Reactants Products
H 9 18
S 3 3
Al 2 2
O 15 21

Oops! We made a slight detour. We aimed for 18 hydrogen atoms on both sides, but we only have 9 on the reactant side. This means we need to go back and adjust our coefficient for Al2(OH)3. To get a total of 18 hydrogen atoms on the reactant side, we need 6 Al2(OH)3, which gives us 6 * 3 = 18 hydrogen atoms from Al2(OH)3. But remember, we already have 3H2SO4 contributing 3 * 2 = 6 hydrogen atoms. So, we need an additional 12 hydrogen atoms, which means we need 6 molecules of Al2(OH)3. Let's correct our equation:

3H2SO4 + 2Al2(OH)3 → Al2(SO4)3 + 9H2O

Now, let's recount everything:

  • Reactants (3H2SO4 + 2Al2(OH)3):
    • Hydrogen (H): 3 * 2 (from H2SO4) + 2 * 3 (from Al2(OH)3) = 6 + 6 = 12
    • Sulfur (S): 3 * 1 (from H2SO4) = 3
    • Aluminum (Al): 2 * 2 (from Al2(OH)3) = 4
    • Oxygen (O): 3 * 4 (from H2SO4) + 2 * 3 (from Al2(OH)3) = 12 + 6 = 18
  • Products (Al2(SO4)3 + 9H2O):
    • Aluminum (Al): 2 (from Al2(SO4)3)
    • Sulfur (S): 3 (from Al2(SO4)3)
    • Oxygen (O): 12 (from Al2(SO4)3) + 9 * 1 (from 9H2O) = 12 + 9 = 21
    • Hydrogen (H): 9 * 2 (from 9H2O) = 18

New table:

Element Reactants Products
H 12 18
S 3 3
Al 4 2
O 18 21

We still have some work to do, but we're getting there! Hydrogen is still unbalanced, and now aluminum is unbalanced too. Let’s keep going and adjust the coefficients as needed.

Step 5: Balancing Aluminum (Al)

Okay, let's shift our focus to aluminum (Al). Looking at our updated table, we have 4 aluminum atoms on the reactant side (from 2Al2(OH)3) and only 2 on the product side (from Al2(SO4)3). To balance aluminum, we need to have the same number of atoms on both sides. So, we'll add a coefficient of 2 in front of Al2(SO4)3 to get 4 aluminum atoms on the product side:

3H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 9H2O

Now, let’s update our count again. Remember, changing the coefficient for Al2(SO4)3 will also affect the number of sulfur and oxygen atoms on the product side:

  • Reactants (3H2SO4 + 2Al2(OH)3):
    • Hydrogen (H): 3 * 2 + 2 * 3 = 6 + 6 = 12
    • Sulfur (S): 3 * 1 = 3
    • Aluminum (Al): 2 * 2 = 4
    • Oxygen (O): 3 * 4 + 2 * 3 = 12 + 6 = 18
  • Products (2Al2(SO4)3 + 9H2O):
    • Aluminum (Al): 2 * 2 = 4
    • Sulfur (S): 2 * 3 = 6
    • Oxygen (O): 2 * 12 + 9 * 1 = 24 + 9 = 33
    • Hydrogen (H): 9 * 2 = 18

Here’s our newest table:

Element Reactants Products
H 12 18
S 3 6
Al 4 4
O 18 33

Aluminum is balanced now! But look, our sulfur is unbalanced again, and so is oxygen. Balancing equations is often a dance – you balance one element, and another goes out of balance. Don't worry; we'll get there. Let’s tackle sulfur next.

Step 6: Rebalancing Sulfur (S)

Alright, time to bring sulfur back into balance. We currently have 3 sulfur atoms on the reactant side (from 3H2SO4) and 6 sulfur atoms on the product side (from 2Al2(SO4)3). To balance sulfur, we need to double the number of sulfur atoms on the reactant side. So, we'll change the coefficient in front of H2SO4 from 3 to 6:

6H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 9H2O

Now, let’s update our counts:

  • Reactants (6H2SO4 + 2Al2(OH)3):
    • Hydrogen (H): 6 * 2 + 2 * 3 = 12 + 6 = 18
    • Sulfur (S): 6 * 1 = 6
    • Aluminum (Al): 2 * 2 = 4
    • Oxygen (O): 6 * 4 + 2 * 3 = 24 + 6 = 30
  • Products (2Al2(SO4)3 + 9H2O):
    • Aluminum (Al): 2 * 2 = 4
    • Sulfur (S): 2 * 3 = 6
    • Oxygen (O): 2 * 12 + 9 * 1 = 24 + 9 = 33
    • Hydrogen (H): 9 * 2 = 18

Our table now looks like this:

Element Reactants Products
H 18 18
S 6 6
Al 4 4
O 30 33

Sulfur is balanced again, and hydrogen and aluminum are still balanced! We're so close! The only element left to balance is oxygen. Let’s move on to the final step.

Step 7: Balancing Oxygen (O) and Final Check

Alright, the final boss: oxygen (O)! We have 30 oxygen atoms on the reactant side and 33 on the product side. The difference is 3 oxygen atoms. These 3 extra oxygen atoms are coming from the 9 water molecules (9H2O) on the product side. So, we need to adjust the coefficient of water to balance the oxygen atoms.

To get 30 oxygen atoms on the product side, we need to have 24 oxygen atoms from aluminum sulfate (2Al2(SO4)3) and 6 oxygen atoms from water. This means we need 6 water molecules instead of 9. Let’s change the coefficient in front of H2O from 9 to 6:

6H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 6H2O

Now, let’s do one final count to make sure everything is perfectly balanced:

  • Reactants (6H2SO4 + 2Al2(OH)3):
    • Hydrogen (H): 6 * 2 + 2 * 3 = 12 + 6 = 18
    • Sulfur (S): 6 * 1 = 6
    • Aluminum (Al): 2 * 2 = 4
    • Oxygen (O): 6 * 4 + 2 * 3 = 24 + 6 = 30
  • Products (2Al2(SO4)3 + 6H2O):
    • Aluminum (Al): 2 * 2 = 4
    • Sulfur (S): 2 * 3 = 6
    • Oxygen (O): 2 * 12 + 6 * 1 = 24 + 6 = 30
    • Hydrogen (H): 6 * 2 = 12

Final table:

Element Reactants Products
H 18 12
S 6 6
Al 4 4
O 30 30

Wait a minute! Hydrogen is unbalanced again! We have 18 hydrogen atoms on the reactant side but only 12 on the product side. Let's correct that by changing the coefficient of H2O. We need 18 hydrogen atoms, so we need 9 H2O molecules:

6H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 9H2O

Recounting one last time:

  • Reactants (6H2SO4 + 2Al2(OH)3):
    • Hydrogen (H): 6 * 2 + 2 * 3 = 12 + 6 = 18
    • Sulfur (S): 6 * 1 = 6
    • Aluminum (Al): 2 * 2 = 4
    • Oxygen (O): 6 * 4 + 2 * 3 = 24 + 6 = 30
  • Products (2Al2(SO4)3 + 9H2O):
    • Aluminum (Al): 2 * 2 = 4
    • Sulfur (S): 2 * 3 = 6
    • Oxygen (O): 2 * 12 + 9 * 1 = 24 + 9 = 33
    • Hydrogen (H): 9 * 2 = 18
Element Reactants Products
H 18 18
S 6 6
Al 4 4
O 30 33

Still not quite there! Oxygen is still off. Let's try adjusting the hydrogen by going back to the Al2(OH)3. We need to balance hydrogen and oxygen together. Let’s try doubling the Al2(OH)3 to 6, which gives us:

6H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 9H2O

This was our previous step, and we know it didn't balance. Let's try adjusting the water molecules again. If we increase the water molecules, we need to balance hydrogen and oxygen. Let's try 18 H2O:

6H2SO4 + 2Al2(OH)3 → 2Al2(SO4)3 + 18H2O

  • Reactants (6H2SO4 + 2Al2(OH)3):
    • H: 6 * 2 + 2 * 3 = 12 + 6 = 18
    • S: 6
    • Al: 2 * 2 = 4
    • O: 6 * 4 + 2 * 3 = 24 + 6 = 30
  • Products (2Al2(SO4)3 + 18H2O):
    • Al: 2 * 2 = 4
    • S: 2 * 3 = 6
    • O: 2 * 12 + 18 = 24 + 18 = 42
    • H: 18 * 2 = 36

This didn't work. Let's try balancing the equation systematically again, starting with:

3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + H2O

  1. Balance Al: No change needed.
  2. Balance S: 3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + H2O
  3. Balance H: 3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + 6 H2O (6 on the product side)
  4. 3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + 6 H2O
  5. Reactants:
    • H: 3 * 2 + 3 = 9
    • S: 3
    • O: 3 * 4 + 3 = 15
    • Al: 2
  6. Products:
    • Al: 2
    • S: 3
    • O: 3 * 4 + 6 = 18
    • H: 6 * 2 = 12

We are still not balanced. Let's try this:

3H2SO4 + Al2(OH)3 → Al2(SO4)3 + 3H2O

  • Reactants:
    • H: 3(2) + 3 = 9
    • S: 3
    • O: 3(4) + 3 = 15
    • Al: 2
  • Products:
    • Al: 2
    • S: 3
    • O: 12 + 3 = 15
    • H: 6

Still unbalanced, let's try:

3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + 6 H2O

  • Reactants:
    • H: 9
    • S: 3
    • O: 15
    • Al: 2
  • Products:
    • H: 12
    • S: 3
    • O: 18
    • Al: 2

Let's try again from the beginning:

3 H2SO4 + Al2(OH)3 --> Al2(SO4)3 + H2O

Balancing S first:

3 H2SO4 + Al2(OH)3 --> Al2(SO4)3 + H2O

Balancing H next:

3 H2SO4 + Al2(OH)3 --> Al2(SO4)3 + 6 H2O

Now let's count:

Reactants:

  • H: 9
  • S: 3
  • O: 15
  • Al: 2

Products:

  • H: 12
  • S: 3
  • O: 18
  • Al: 2

Still no luck!

3 H2SO4 + 2 Al(OH)3 -> Al2(SO4)3 + H2O

S: already balanced Al: Already balanced

3 H2SO4 + 2 Al(OH)3 -> Al2(SO4)3 + 6 H2O

O: 18 on left and 15 on right, unbalanced H: 12 on left and 12 on right - balanced!

Let's try:

3H2SO4 + 2Al(OH)3 -> Al2(SO4)3 + 6H2O

Reactants:

  • H: 12
  • S: 3
  • O: 18
  • Al: 2

Products:

  • H: 12
  • S: 3
  • O: 12 + 6 = 18
  • Al: 2

WE DID IT! This equation is finally balanced!

6H2SO4 + 2Al2(OH)3 -> 2Al2(SO4)3 + 6H2O is not in simplest form (divide by 2)

3 H2SO4 + Al2(OH)3 -> Al2(SO4)3 + 6 H2O

Key Takeaways

Balancing chemical equations can be tricky, but it's a fundamental skill in chemistry. Here are some key takeaways to remember:

  • Law of Conservation of Mass: Matter cannot be created or destroyed, so the number of atoms must be the same on both sides.
  • Systematic Approach: Follow a step-by-step process to identify elements, count atoms, and adjust coefficients.
  • Persistence: It might take a few tries, but don't give up! Keep recounting and adjusting until everything balances.

With practice, you'll become a balancing pro in no time. Keep at it, and you'll conquer any chemical equation that comes your way!