Answer:
KOH
Explanation:
Chemical reaction:
2K + 2H₂O → 2KOH + H₂
Element ratio of K.
K = 1
Because only potassium is present.
Element ratio of H₂O.
2 : 1
in water ratio of element is 2 : 1 because two hydrogen and one oxygen atom present.
Element ratio of KOH
1 : 1 : 1
in KOH elemental ratio is 1 : 1 : 1 because one potassium one hydrogen and one oxygen atom are present.
Element ratio of H₂.
2
Just two atoms of hydrogen are present.
Answer:
1. d. The reaction is spontaneous in the reverse direction at all temperatures.
2. c. The reaction is spontaneous at low temperatures.
Explanation:
The spontaneity of a reaction is associated with the Gibbs free energy (ΔG). When ΔG < 0, the reaction is spontaneous. When ΔG > 0, the reaction is non-spontaneous. ΔG is related to the enthalpy (ΔH) and the entropy (ΔS) through the following expression:
ΔG = ΔH - T. ΔS [1]
where,
T is the absolute temperature (T is always positive)
<em>1. What can be said about an Endothermic reaction with a negative entropy change?</em>
If the reaction is endothermic, ΔH > 0. Let's consider ΔS < 0. According to eq. [1], ΔG is always positive. The reaction is not spontaneous in the forward direction at any temperature. This means that the reaction is spontaneous in the reverse direction at all temperatures.
<em>2. What can be said about an Exothermic reaction with a negative entropy change?</em>
If the reaction is exothermic, ΔH < 0. Let's consider ΔS < 0. According to eq. [1], ΔG will be negative when |ΔH| > |T.ΔS|, that is, at low temperatures.
Answer:
B. 4 Fe + 3 0₂---> 2 Fe₂O3
Explanation:
(A) Ir + O₂--> IrO₂ No: Ir is iridium
(B) 4 Fe + 3 0₂---> 2 Fe₂O3 Yes: Fe is iron and O is oxygen, and the equation is balanced.
(C) I+ 0₂ ---> 10₂ No: I is iodine
(D) 3 Ir + 0₂ -> 6 Ir₂03 No: I is iodine