a. An oxidation reaction. An oxidation reaction is a type of chemical reaction that involves a transfer of electrons between two species.
The nonmetal elements have a negative charge.
<u>Answer:</u>
<em>The system is the Answer
</em>
<em></em>
<u>Explanation:</u>
System is the region which is taken into consideration.
While we perform a chemical reaction the system is the substance taken in the container.
So, A thermodynamic system is the amount of matter or the region in universe which is under the study.
The region outside the beaker are called as surroundings.
The beaker (the surface which separates the system from its surroundings) is said to be the boundary
System + surroundings = universe
<h2>Hey There!</h2><h2>_____________________________________</h2><h2>Answer:</h2>
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<h2>_____________________________________</h2><h2>CALORIMETER:</h2>
Calorimeter is device used for the measurement of heat. In a calorimeter we can use the temperature change of water to quantify an amount of heat. A calorimeter just captures all the energy released (or absorbed) by a reaction in the water. So Option A and B are wrong as calorimeter don't have anything to do with providing the heat or letting the the heat in, as it is the insulated calorimeter too.
<h2>_____________________________________</h2><h2>Energy in the reaction:</h2>
In the formation of any bond there is equal amount of heat required as to break that bond. It means Energy released in the making of bond is equal to the energy required in the breaking of the bond. So Option D is wrong as it says we need more energy in making then breaking.
<h2>_____________________________________</h2><h2>Enthalpy:</h2>
Enthalpy is the total heat content of the system. As we provide energy to the reactants and the product is formed, so The enthalpy(heat content) of product is more than the Enthalpy of the reactant, Thus Option C is correct.
Enthalpy is denoted by H or Q, its formula is,
H = U + PV
Where,
U is internal energy
PV is equals to Work done ; P = Pressure, V = Volume
<h2>_____________________________________</h2><h2>Best Regards,</h2><h2>'Borz'</h2><h2> </h2>