how do i balance the following(fill in the blanks):

1.) __BF3 + __Li2SO3 --> __B2(SO3)3 + __LiF

2.) __CaCO3 + __H3PO4 --> __Ca3(PO4)2 + __H2CO3

3.) __B2Br6 + __HNO3 --> __B(NO3)3 + __HBr

2BF3 + 3Li2SO3 --> B2(SO3)3 + 6LiF

I made a typo. I typed 2,3,1,3 and I SHOULD have typed 2,3,1 6.
In answer to your question, no. The first rule of balancing equations is that you may change ONLY the coefficients. You may NOT change the subscripts. Therefore, placing a 2 as a coefficient for BF3 (2BF3) means you multiply the B and the F by 2 which gives you 2 B atoms and 6 F atoms. And that balances with the B2(SO3(3 (2 B atoms there) and the 6LiF (6 F atoms there).

#1. 2,3,1,3 but check it to make sure.

The others. You need to learn to do these yourself. Tell us what you don't understand about the process and we can help you through it.

if i were to put 2 for the first blank does it go to the B and the F3?

if it does wouldn't that mean the first would be B2F6 and the last would be Li3F3, so the F would be unbalanced?

i don't get that part...

i think im still a little confused

would the next one #2 be 3, 2, 1, 3

absolutely perfect. Want to go for two straight?

ummm 1,6,2,6????

idk haha

B2Br6 + __HNO3 --> __B(NO3)3 + __HBr

You ALWAYS know if the equation is balanced BECAUSE you ALWAYS check it after finishing. That way you will know if you made an error. Let's check this one.
I'll put in your numbers.
B2Br6 + 6HNO3 ==> 2B(NO3)3 + 6HBr

I see 2 B on the left and 2 on the right.
I see 6 Br on the left and 6 on the right.
I see 6H on the left and 6 on the right.
I see 6 NO3^- on the left and 6 on the right.
Looks to me as if you scored again! Good work!

oh alright i get it thanks :)

To balance chemical equations, you need to ensure that the number of atoms of each element is the same on both sides of the equation. Here is how you can balance each of the given chemical equations:

1.) __BF3 + __Li2SO3 --> __B2(SO3)3 + __LiF

To balance this equation, start by counting the number of atoms of each element on both sides of the equation:

On the left side:
B: 1
F: 3
Li: 2
S: 1
O: 3

On the right side:
B: 2
F: 1
S: 3
O: 9
Li: 1

Since the numbers of atoms on each side are not balanced, you need to adjust the coefficients in front of each compound.

By trying different coefficients, you can balance the equation as follows:

2BF3 + 3Li2SO3 --> B2(SO3)3 + 6LiF

Now, recheck the number of atoms of each element:

On the left side:
B: 2
F: 6
Li: 6
S: 3
O: 9

On the right side:
B: 2
F: 6
S: 3
O: 9
Li: 6

The equation is now balanced.

2.) __CaCO3 + __H3PO4 --> __Ca3(PO4)2 + __H2CO3

Start by counting the number of atoms of each element on both sides of the equation:

On the left side:
Ca: 1
C: 1
O: 3
H: 3
P: 1

On the right side:
Ca: 3
P: 2
O: 8
H: 2
C: 1

The numbers of atoms on each side are not balanced.
By adjusting the coefficients, the equation can be balanced as follows:

3CaCO3 + 2H3PO4 --> Ca3(PO4)2 + 3H2CO3

After balancing, recheck the number of atoms of each element:

On the left side:
Ca: 3
C: 3
O: 9
H: 6
P: 6

On the right side:
Ca: 3
P: 6
O: 9
H: 6
C: 3

The equation is now balanced.

3.) __B2Br6 + __HNO3 --> __B(NO3)3 + __HBr

Start by counting the number of atoms of each element on both sides of the equation:

On the left side:
B: 2
Br: 6
H: 1
N: 1
O: 3

On the right side:
B: 1
N: 3
O: 9
H: 1
Br: 1

Since the numbers of atoms on each side are not balanced, you need to adjust the coefficients in front of each compound.

By trying different coefficients, you can balance the equation as follows:

B2Br6 + 6HNO3 --> 3B(NO3)3 + 6HBr

Now, recheck the number of atoms of each element:

On the left side:
B: 2
Br: 6
H: 6
N: 6
O: 18

On the right side:
B: 6
N: 18
O: 54
H: 6
Br: 6

The equation is now balanced.