Question

fill in the blank 2 points
balance the following equation:
1
al + 2
o₂ --> 3
al₂o₃

Explanation:

Step1: Identify atoms to balance

We need to balance the equation \( \text{Al} + \text{O}_2
ightarrow \text{Al}_2\text{O}_3 \). First, list the number of each atom on both sides. On the left: Al = 1, O = 2. On the right: Al = 2, O = 3.

Step2: Balance oxygen atoms

Find the least common multiple of 2 and 3, which is 6. So, for \( \text{O}_2 \), multiply by 3 (to get 6 O atoms: \( 3\times2 = 6 \)), and for \( \text{Al}_2\text{O}_3 \), multiply by 2 (to get 6 O atoms: \( 2\times3 = 6 \)). Now the equation is \( \text{Al} + 3\text{O}_2
ightarrow 2\text{Al}_2\text{O}_3 \).

Step3: Balance aluminum atoms

Now, on the right, Al atoms are \( 2\times2 = 4 \). So, multiply Al on the left by 4. The balanced equation is \( 4\text{Al} + 3\text{O}_2
ightarrow 2\text{Al}_2\text{O}_3 \).

Looking at the blanks:

• First blank (Al coefficient): 4
• Second blank (O₂ coefficient): 3
• Third blank (Al₂O₃ coefficient): 2 (but the problem shows the third blank as for Al₂O₃, and in the given structure, let's check the positions. Wait, the original blanks: first is Al, second is O₂, third is Al₂O₃. So:

First blank (Al): 4

Second blank (O₂): 3

Third blank (Al₂O₃): 2

Wait, but the user's image shows the blanks as:

1. Al (first blank)

1. O₂ (second blank)

1. Al₂O₃ (third blank)

So let's re-express the balancing:

Start with \( \text{Al} + \text{O}_2
ightarrow \text{Al}_2\text{O}_3 \)

Balance O:

Multiply \( \text{O}_2 \) by 3: \( 3\text{O}_2 \) (gives 6 O)

Multiply \( \text{Al}_2\text{O}_3 \) by 2: \( 2\text{Al}_2\text{O}_3 \) (gives 6 O and 4 Al)

Then balance Al: multiply Al by 4: \( 4\text{Al} \)

So the coefficients are:

4 for Al, 3 for O₂, 2 for Al₂O₃.

But the user's blanks:

First blank (Al): 4

Second blank (O₂): 3

Third blank (Al₂O₃): 2

Wait, but in the image, the third blank is labeled as Al₂O₃, so:

Answer:

First blank (Al): 4

Second blank (O₂): 3

Third blank (Al₂O₃): 2

(But let's check the problem's blank positions. The first blank is before Al, second before O₂, third before Al₂O₃. So:

1. 4

1. 3

1. 2)