Which of the following chemical equations follows the law of conservation of mass?

The third choice

Explanation:

The law of conservation of mass tells us that the mass of the reactants and products in a chemical reaction will be equal to one another. Equations follow the law of conservation of mass when they are balanced, which means that they have the same number and type of atoms on each side.

When individual atoms are counted, the third choice has the same number and type of atoms on each side: 1 gallium, three cesium and three fluorine.

Explanation:

Hello.

In this case, since the chemical reaction is:

We can write the rate ratio between N2O5 and NO2 as shown below:

Since N2O5 is consumed and NO2 produced at a rate of 8.00 mol/s, therefore, the rate of disappearance is N2O5 is:

Which is negative since N2O5 is a reactant.

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