Firstly the limiting reactant should be identified. Limiting reactant is the reactant that is in limited supply, the amount of product formed depends on the moles present of the limiting reactant.
the stoichiometry of x to y = 1:2
1 mole of x reacts with 2 moles of y
if x is the limiting reactant, there are 3 moles of x, then 6 moles of y should react, however there are only 4 moles of y. Therefore y is the limiting reactant and x is in excess.
4 moles of y reacts with 2 moles of x
since there are 3 moles of x initially and only 2 moles are used up, excess amount of x is 1 mol thats in excess.
Combustion can be defined as the reaction of a compound with oxygen. The enthalpy of combustion of octane is 
for 
.
<h3>What is the enthalpy of reaction?</h3>
The enthalpy of reaction is the amount of heat energy absorbed or lost by the molecules in the chemical reaction.
The enthalpy of combustion is the amount of heat energy released by the compound in the reaction with oxygen.
The reaction in which heat is liberated with the reaction of a compound with oxygen has an enthalpy of combustion, equivalent to the enthalpy of reaction.
The combustion of octane can be given as:
Thus, the reaction has combustion energy equivalent to the enthalpy of the reaction is . Thus, option B is correct.
Learn more about enthalpy of reaction, here:
brainly.com/question/1657608
During endothermic phase change, the potential energy of the system always increases while the kinetic energy of the system remains constant. The potential energy of the reaction increases because energy is been added to the system from the external environment.
<u>Explanation</u>:
- Those are three distinct methods for demonstrating a specific energy condition of an object. They don't affect one another.
- "Potential Energy" is a relative term showing a release of possible energy to the environment. If we accept its pattern as the overall energy state of a compound, at that point, an endothermic phase change would infer an increase in "potential" as energy is being added to the compound by the system.
- A phase change will display an increase in the kinetic energy at whatever point the compound is transforming from a high density to a low dense phase. The kinetic energy will decrease at whatever point the compound is transforming from a less dense to high dense phase.
Answer:
[Cr(NH3)6.]C13
Explanation:
Alfred Werner's coordination theory (1893) recognized two kinds of valency;
Primary valency which are nondirectional and secondary valency which are directional.
Hence, the number of counter ions precipitated from a complex depends on the primary valency of the central metal ion in the complex.
We must note that it is only these counter ions that occur outside the coordination sphere that can be precipitated by AgNO3.
If we consider the options carefully, only [Cr(NH3)6.]C13 possess counter ions outside the coordination sphere which can be precipitated when treated with aqueous AgNO3.
