I’m so sorry about the other guy! The answer is A. Infertile soil honey
God Bless!! <3
Physical change because it's only changing the shape of the gold.
Answer:
Option 3. The catalyst does not affect the enthalpy change (
) of a reaction.
Explanation:
As its name suggests, the enthalpy change of a reaction () is the difference between the enthalpy of the products and the reactants.
On the other hand, a catalyst speeds up a reaction because it provides an alternative reaction pathway from the reactants to the products.
In effect, a catalyst reduces the activation energy of the reaction in both directions. The reactants and products of the reaction won't change. As a result, the difference in their enthalpies won't change, either. That's the same as saying that the enthalpy change of the reaction would stay the same.
Refer to an energy profile diagram. Enthalpy change of the reaction measures the difference between the two horizontal sections. Indeed, the catalyst lowered the height of the peak. However, that did not change the height of each horizontal section or the difference between them. Hence, the enthalpy change of the reaction stayed the same.
The pressure of the oxygen gas collected : 718 mmHg
<h3>Further explanation</h3>
Given
P tot = 748 mmHg
P water vapour = 30 mmHg
Required
P Oxygen
Solution
Dalton's law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases
Can be formulated:
P tot = P1 + P2 + P3 ....
The partial pressure is the pressure of each gas in a mixture
P tot = P H₂O + P Oxygen
P Oxygen = 748 mmHg - 30 mmHg
P Oxygen = 718 mmHg
