Question

Examine the equation below.

__NaCl + __CaF2 → __NaF +__CaCl2


To adhere to the law of conservation of mass, which set of coefficients must this equation have, in sequence from left to right?

(1 point)
Responses

2, 1, 3, 1
2, 1, 3, 1

2, 1, 2, 1
2, 1, 2, 1

1, 3, 1, 3
1, 3, 1, 3

2, 2, 2, 2

Answer 1

To satisfy the law of conservation of mass, the number of atoms of each element on the reactants side must equal the number on the products side.

Let's analyze the equation:

**Unbalanced equation:**
NaCl + CaF2 → NaF + CaCl2

Now, let's write down the number of each type of atom on both sides.

### Reactants:
- **Na**: 1 (from NaCl)
- **Cl**: 1 (from NaCl)
- **Ca**: 1 (from CaF2)
- **F**: 2 (from CaF2)

### Products:
- **Na**: 1 (from NaF)
- **Cl**: 2 (from CaCl2)
- **Ca**: 1 (from CaCl2)
- **F**: 1 (from NaF)

Now we can see that:
- Sodium (Na): 1 on both sides (balanced)
- Chlorine (Cl): 1 on the reactants side and 2 on the products side (not balanced)
- Calcium (Ca): 1 on both sides (balanced)
- Fluorine (F): 2 on the reactants side and 1 on the products side (not balanced)

To balance this equation, we can use the following coefficients:

- Place **2** in front of NaCl and NaF to balance Na and Cl.
- Place **1** in front of CaF2 and **1** in front of CaCl2, since they are already balanced.

This gives us the balanced equation:

2 NaCl + 1 CaF2 → 2 NaF + 1 CaCl2

Now let's summarize the coefficients:

- Coefficient for NaCl: 2
- Coefficient for CaF2: 1
- Coefficient for NaF: 2
- Coefficient for CaCl2: 1

Thus, the correct set of coefficients in sequence from left to right is:

**2, 1, 2, 1**.

Therefore, the answer is **2, 1, 2, 1**.