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What is the relationship between enthalpy and temperature?
Enthalpy is the amount of energy in a system and when this changes (when a reaction happens), the energy is either released (exothermic) or absorbed (endothermic) and this energy is usually released or absorbed as heat. Therefore when the enthalpy decreases, heat is released from the system making it exothermic. In contrast, when the enthalpy increases, heat is absorbed making it endothermic.
What is the difference between path function and state function?
state function did not depend on the path , it depends on the initial and final point of the system where as path function depends on the path of the reaction.
What is the difference between state table and truth table?
A state table defines the behaviour of the of the sequantial function
Internal energy and enthalpy how differ and relate to each other?
Enthalpy mathematically is the sum of the internal energy and work done in a process.internal energy is the sum of the kinetic energy,potential energy,vibrational energies etc
What is the difference between pure and impure function in computer language?
A pure function is one function that has no side effects or output and doesn't depend on any state beyond its local state's means it can be replaced by any other pure function which returns same result given the same inputs.This property is often referred as referential transparency
What is one reason to use Hess's law?
Hess's law allows you to calculate the enthalpy change of a reaction by using the enthalpy changes of other reactions. This is particularly useful when direct measurement of the desired reaction is not feasible.
Why absolute value of enthalpy of system cannot be measured?
The absolute value of enthalpy cannot be measured because enthalpy is a state function, which means its value depends on the initial and final states rather than the absolute value. Only changes in enthalpy can be measured experimentally through processes like calorimetry.
Does the overall enthalpy change of a chemical reaction depend on the reaction pathway?
No, the overall enthalpy change of a chemical reaction is independent of the reaction pathway. This is because enthalpy is a state function, meaning it only depends on the initial and final states of the system, not on how the system reached those states.
When does enthalpy become zero?
Enthalpy can be zero for a pure substance at its standard state, where it is defined as the enthalpy of formation. This typically occurs at a reference temperature and pressure specified for the substance.
What Thermodynamic state function measures the maximum electric work in a fuel cell?
Gibbs free energy is the thermodynamic state function that measures the maximum electrical work that can be obtained from a fuel cell at constant temperature and pressure. It represents the balance between the system's enthalpy, entropy, and temperature.
What is meant by state function?
A state function is one that depends only on the state of the system, not on how it got there. In quantum mechanics the states of interest are usually energy states. In the formalism of quantum mechanics, the state of a system at a given time is described by a complex wave function, also referred to as state vector in a complex vector space. This abstract mathematical object allows for the calculation of probabilities of outcomes of concrete experiments. For example, it allows one to compute the probability of finding an electron in a particular region around the nucleus at a particular time. Some of the states of interest are electron spin, electron energy level, harmonic oscillation frequencies, and the energy of individual particles, atoms, and molecules. Note that state functions are particularly appropriate for quantum mechanics where changes occur in discrete quanta rather than as a continuous path.
Why is the enthalpy of sublimation is equal to the sum of enthalpy of fusion and enthalpy of vaporization?
The enthalpy of sublimation is equal to the sum of the enthalpy of fusion (solid to liquid) and the enthalpy of vaporization (liquid to gas) because sublimation is the direct transition from solid to gas phase without passing through the liquid phase. This means that the energy required to break the bonds in the solid and to overcome the intermolecular forces in the liquid are added together to give the total energy needed for sublimation.
What do the symbols mean Delta Hr Hf Hc Hn Ha in chemistry btw i know theyre enthalpy changes?
ΔH: Represents the change in enthalpy of a reaction. ΔHf: Standard enthalpy of formation, which is the enthalpy change when one mole of a substance is formed from its elements in their standard states. ΔHc: Standard enthalpy of combustion, which is the enthalpy change when one mole of a substance is completely burned in oxygen. ΔHn: Standard enthalpy of neutralization, which is the enthalpy change when an acid and a base react to form one mole of water under standard conditions. ΔHa: Standard enthalpy of atomization, which is the enthalpy change when one mole of gaseous atoms is formed from an element in its standard state.
Why does oxygen gas not have an enthalpy of formation but ozone does?
Oxygen gas (O2) does not have an enthalpy of formation because it is an element in its standard state, which has an enthalpy of formation of zero by definition. Ozone (O3), on the other hand, is a compound and has a defined enthalpy of formation because it is formed from its elements in their standard states.
What kind of energy of water increases as the water is heated by the coal?
As water is heated in a coal-fired boiler, the enthalpyof the water increases. Note that enthalpy is defined as:H = U + pVwhereH is the enthalpy of the systemU is the internal energy of the systemp is the pressure at the boundary of the system and its environmentV is the volume of the system.Also note that as a state function, enthalpy is expressed as a value relative to some reference state. For water, this is typically liquid water at the triple point, although other conventions are used such as liquid water at the normal freezing point.
What does Hesses law state?
The enthalpy of a reaction is the sum of the enthalpies of intermediate reaction.
Are enthalpy changes accompanying a change of state are smaller or larger than the heating substance at each state?
Larger.
