D is the answer, I believe.
An isolated system is one that allows neither heat or matter to enter or exit, and since the liquid remained the same temperature, one can conclude that neither energy nor matter is passing through.
Answer:
Could be either spontaneous or nonspontaneous depending on the temperature
Explanation:
For a reaction to be spontaneous, Gibbs free energy must be negative.
The relation between enthalpy, entropy and temperature is as follows:

ΔG is change Gibbs free energy, ΔH is change in enthalpy, ΔS is change in entropy and T is temperature.
In the given condition, ΔH is negative and ΔS is negative. As ΔS is also negative then ΔG cannot be negative at all temperature (Particulary at high temperature) and thus, reaction could be nonspontaneous.
Therefore, in the given the reaction, could be either spontaneous or nonspontaneous depending on the temperature.
Answer: Gas
Explanation:
Gas. The arrows represent direction. They are moving around in the box extremely fast, and are not compact like a solid or liquid.
Answer:
Lithium oxide, Li₂O.
Explanation:
Hello!
In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:
Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:
Thus, we perform the operations in order to obtain:
So we solve for x as shown below:
Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
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