Which chemical equation below is balanced to correctly represent the Law of Conservation of Mass?

The 3rd equation.

Cl2 + 2NaBr —> 2NaCl + Br2

Explanation:

The law of conservation of matter (mass) states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another. This implies that unbalanced chemical equation shows that matter (mass) has been created or destroyed.

Now, we shall determine which equation is balanced as follow:

1. 2Cl2 + NaBr —> 2NaCl + Br2

Reactant >>>>>>>> Product

4 Cl >>>>>>>>>>>> 2 Cl

1 Na >>>>>>>>>>>> 2 Na

1 Br >>>>>>>>>>>> 2 Br

Thus, the equation is not balanced.

2. Cl2 + NaBr —> NaCl + Br2

Reactant >>>>>>>> Product

2 Cl >>>>>>>>>>>> 1 Cl

1 Na >>>>>>>>>>>> 1 Na

1 Br >>>>>>>>>>>> 2 Br

Thus, the equation is not balanced.

3. Cl2 + 2NaBr —> 2NaCl + Br2

Reactant >>>>>>>> Product

2 Cl >>>>>>>>>>>> 2 Cl

2 Na >>>>>>>>>>> 2 Na

2 Br >>>>>>>>>>>> 2 Br

Thus, the equation is balanced.

From the illustration made above only the 3rd equation is balanced. And this is in line with the law of the Conservation of matter (mass) as matter (mass) was not created nor destroyed during the chemical reaction but was transferred to other forms.

sry but any answer choices

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.