Question

Identify the missing coefficient in the balanced equation and classify the type of reaction.

2H3PO4 +3Ba(OH)2 — Baz(PO4)2 +
H2O
6; Neutralization
3; Combustion
6; Combustion
3; Neutralization

Answer 1

6; Neutralization

Step-by-step explanation:

`2H_3 PO_4+3Ba(OH)_2>Ba_3 (PO_4)_2+H_2 O`

(Unbalanced)

Balancing is making the number of atoms of each element same on both the sides (reactant and product side).

To find the number of atoms of each element we multiply coefficient and the subscript

For example
`5Ca_1Cl_2` contains

5 × 1 = 5 ,Ca atoms and

5 × 2 = 10, Cl atoms

If there is a bracket in the chemical formula

For example
`3Ca_3 (P_1 O_4 )_2` we multiply coefficient × subscript × number outside the bracket to find the number of atoms

(Please note: 3 is the coefficient, and if there is no number given then 1 will be the coefficient )

So

3 × 3 = 9 , Ca atoms

3 × 1 × 2 = 6, P atoms

3 × 4 × 2 = 24, O atoms are present

Reactant side Number of atoms or groups Product side

of each element

3 Ba 3

2
`PO_4` 2

12 H 2

6 O (Exclude O of
`PO_4`) 1

To balance H and O, multiply
`H_2O` by 6 so we have

`2H_3 PO_4+3Ba(OH)_2>Ba_3 (PO_4)_2+6 H_2 O`

Reactant side Number of atoms or groups Product side

of each element

3 Ba 3

2
`PO_4` 2

12 H 12

6 O (Exclude O of
`PO_4`) 6

Balanced!!!!

Acid and base reacts to form salt and water is called a neutralization reaction.

Answer 2

Option 6 ) Neutralization

Step-by-step explanation:

For this case, the missing coefficient would be a "6" before the H₂O, within final products (right side of the equiation), hence, the final reaction should be:

2H₃PO₄ + 3Ba(OH)₂ ------> Ba₃(PO₄)₂ + 6H₂O

You should have in mind that the amount of atoms at each side of the chemical equation should be the same, so as to comply with the principle of mass conservation. If you add "6" on the left side of the H₂O, the equation will be balanced (for each side, lef and right, you will have: 12H, 2P, 14O and 3Ba)

Lastly, this is a chemical neutralization reaction, where an acid (H₃PO₄) is reacting with a base (Ba(OH)₂) in order to finally obtain a neutral salt (Ba₃(PO₄)₂) and water (H₂O)