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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The temperature change of a 36-gram sample of water is <u>4.61 K</u>
Temperature is the degree of the average kinetic energy of the debris in an item. while the temperature will increase, the movement of this debris additionally will increase. Temperature is measured with a thermometer or a calorimeter.
heat = msΔt
695 Joule = 36 × 4.186 × Δt
Δt = 695/ 36 × 4.186
= <u>4.61 K</u>
Temperature is just a dimension that indicates the common kinetic energy of 1 atom or molecule. as a result, when we are saying something is warm or bloodless, we're generally using any other reference point to define the hotness and coldness of a frame.
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The ccorrect answer is C a generator tubrine
a mole is defined as the amount of substance that contains as many atoms, molecules, icons, electron or any other elementary entities as there are exactly 12 gm of. of carbon atoms. the number of 12 gm of. Is called Avogadro's number