Considering the reaction of hydrogen and oxygen to produce water. If 24.6 g of water is produced and 2.9 g of hydrogen is used, the amount of oxygen needed is 21.87 grams
The best way to solve this question is to write out the reaction between hydrogen and oxygen that resulted in the formation of water.
So, we have:

From the above reaction;
2 moles of hydrogen gas reacted with 1 mole of oxygen to produce 2 moles of water.
If;
- 1 mole of O₂ = 32 grams of O₂
- 2 mole of H₂O = 2 × 18 grams of H₂O
- 2 mole of H₂O = 36 grams of H₂O
We can deduce that since 1 mole of O₂ produced 2 moles of H₂O;
Thus, 32 grams of O₂ is needed to produce 36 grams of H₂O.
∴
To produce, 24.6 grams of H₂O, we have:

= 21.87 grams of oxygen.
Therefore, we can conclude that the amount of oxygen needed is 21.87 grams.
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Answer:
O-18 is used as a tracer in many hydrologic studies. It is most often used as a component in a mixing-model and hydrograph separation, as O-18 acts conservatively and is applied naturally and uniformly over broad areas. O-18 can be used when different sources (old water/new water) have different isotopic values.
Answer:
Put the soil in one area and keep the water heated so the water can evaporate.
Explanation:
Answer : The correct expression for equilibrium constant will be, ![K=[O_2]^5](https://tex.z-dn.net/?f=K%3D%5BO_2%5D%5E5)
Explanation :
Equilibrium constant : It is defined as the equilibrium constant. It is defined as the ratio of concentration of products to the concentration of reactants.
The equilibrium expression for the reaction is determined by multiplying the concentrations of products and divided by the concentrations of the reactants and each concentration is raised to the power that is equal to the coefficient in the balanced reaction.
As we know that the concentrations of pure solids are constant that is they do not change. Thus, they are not included in the equilibrium expression.
The given equilibrium reaction is,

The expression of
will be,
![K=[O_2]^5](https://tex.z-dn.net/?f=K%3D%5BO_2%5D%5E5)
Therefore, the correct expression for equilibrium constant will be, ![K=[O_2]^5](https://tex.z-dn.net/?f=K%3D%5BO_2%5D%5E5)