57
the amount of oxygen in the reactants is 4 atoms. in the products, the oxygen is distributed to water (h20) and oz gas.
which coefficients would be placed in front of water and oxygen?
o
2 in front of water and 2 in front of oxygen
1 in front of water and 2 in front of oxygen
1 in front of water and 1 in front of oxygen
2 in front of water and 1 in front of oxygen
o

2 in front of water and 1 in front of oxygen

Explanation:

Chemical equation:

H₂ + O₂  → H₂O + O₂

Balanced chemical equation:

2H₂ + 2O₂  → 2H₂O + O₂

In order to balance the equation we should put the coefficient 2 in front of water and one in front of oxygen.

There are four hydrogen and four oxygen atoms on both side of equation so it is balanced. The balanced equation also follow the law of conservation of mass.

According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.

This law was given by french chemist  Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.