I would say the first three. But I'm not 100% sure. I'm truly sorry if it's wrong
Answer:
b. ΔE rxn is a measure of heat
Explanation:
a. ΔHrxn is the heat of reaction. <em>TRUE. </em>ΔHrxn or change in enthalpy of reaction is per definition the change in heat that is involved in a chemical reaction.
b. ΔErxn is a measure of heat. <em>FALSE. </em>Is the change in internal energy of a reaction
c. An exothermic reaction gives heat off heat to the surroundings. <em>TRUE</em>. An exothermic reaction is a chemical reaction that releases heat.
d. Endothermic has a positive ΔH. <em>TRUE. </em>When a process is exothermic ΔH<0 and when the process is endothermic ΔH>0
e. Enthalpy is the sum of a system's internal energy and the product of pressure and volume. <em>TRUE. </em>Under constant pressure and volume the formula is ΔH = ΔE + PV
I hope it helps!
All Elements are obtained in the periodic table & water is Not an element it is a compound.
Answer: Revoke the driver's license for at least 12 months
Explanation:
Chemical tests are used in order to measure the amount of drugs or alcohol that is in the body of a person when the person was arrested. To do this, samples of the urine or blood of the person can be taken and the result will be used to know if the person was driving under the influence of alcohol or not.
If the person refuse a legal chemical test issued by a law enforcement officer, the Division of Motor Vehicles is required to revoke the the driver's license of the person for at least 12 months.
Answer:
The correct answer is B. It is spontaneous only at low temperatures.
Explanation:
In thermodynamics, the Gibbs free energy is a thermodynamic potential that can be used to calculate the maximum of reversible work that may be performed by a thermodynamic system at a constant temperature and pressure.
The spontaneity of a reaction is given by the equation:
ΔG = ΔH - TΔS
where:
ΔH: enthalpy variation
T: absolute temperature
ΔS: entropy variation
As the reaction is exothermic, ΔH<0
As the reaction order increases (the reagents are solid and gas and their product is solid), ΔS<0
Therefore, the reaction will be spontaneous when ΔG is negative.
ΔG = ΔH - TΔS
That is, the entropy term must be smaller than the enthalpy term.
Hence, the reaction will be spontaneous only at low temperatures.
