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but answer is given b i also thing it's wrong

q is not a state function..

Theinternal energy is astate functionof a system, because its value depends only on the currentstateof the system and not on the path taken or processes undergone to prepare it. It is an extensive quantity.

Enthalpyis defined as astate functionthat depends only on the prevailing equilibrium stateidentified by the system'sinternal energy, pressure, and volume. It is an extensivequantity.

Pressurecan also be classically defined as Force per unit Area. The ratio of twoextensive properties is anintensiveproperty.

Hence, pressure is the right answer

q is not a state function

Work is not a state function because it is proportional to the distance an object is moved, which depends on the path used to go from the initial to final state

water turns to steam at 100°Cso the state of water will be gaseous.

273 Kelvin is 0°Cwater is ice at 0°C. so the state of water will be solid.

132.6 * 10^3/ 66 = 2009

hence, option (b)

The standard Gibbs free energy of formation of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of that substance from its component elements, at their standard states (the most stable form of the element at 25 °C and 100 kPa).

(3) system is at equilibrium.At equilibrium, both forward and backward reactions occur at the same rate. So the total energy change is zero.

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Reversible changesA substance can return to its original state.The chemical properties of the substance do not change.Most physical changes are reversible changes.Irreversible changesA substance cannot return to its original state.The chemical properties of the substance change.All chemical changes are irreversible changes.

zerodelta G at equilibrium is zero

no

The equilibrium constant NEVER depends on the type of catalyst used, no matter the nature of the reaction (homogeneous or heterogeneous). The equilibrium constant is a thermodynamic variable that is linked to the free Gibbs energy, and also varies with the temperature according to the Van't Hoff Equation. Catalysts only speed up the reaction rates; they don't have any effect on the equilibrium of the reactions.

thank you

All changes in the world are one of the two types – Reversible changes and irreversible changes. A change which can happen backward, that is, can be reversed is called a reversible change. If you keep water in the freezer for some time, it transforms into ice. But as soon as you take it out of the freezer, it turns into water again. This is a reversible change. Similarly, if you boil water, it evaporates and becomes water vapor. When you cool this vapor down, it turns back to waterA change which cannot happen backward, that is, it cannot be reversed is called an irreversible change.When you burn a piece of paper, it turns to ash. It cannot become paper again. Your height cannot decrease. These are irreversible changes. They cannot be reversed at all.

A metal above hydrogen in reactivity series gives hydrogen with acids

In thermodynamics, a reversible process is a process whose direction can be "reversed" by inducing infinitesimal changes to some property of the system via its surroundings, with no increase in entropy. Throughout the entire reversible process, the system is in thermodynamic equilibrium with its surroundings.

Anisothermal processis achangeof asystem, in which thetemperatureremains constant: ΔT=0. This typically occurs when a system is in contact with an outside thermal reservoir (heat bath), and the change in the system will occur slowly enough to allow the system to continue to adjust to the temperature of the reservoir throughheatexchange. In contrast, anadiabatic processis where a system exchanges no heat with its surroundings (Q=0). In other words, in an isothermal process, the value ΔT=0 and therefore the change ininternal energyΔU=0 (only for an ideal gas) but Q≠0, while in an adiabatic process, ΔT≠0 but Q=0.

Isobaric Process

Anisobaric processis one where the pressure of the system (often a gas) stays constant. 'Iso' means the same, and 'baric' means pressure. Pressure is related to the amount of force that the molecules apply to the walls of the container. Imagine that you have a gas inside a movable piston and you heat that gas up. By heating the gas up you make the molecules move faster, which would normally increase the pressure. But at the same time the piston expands, increasing the volume and giving the molecules more room to move. Since the walls of the container are now bigger, the pressure can stay the same even though the molecules are moving faster. That makes it an isobaric process.

Isothermal Process

Anisothermal processis one where the temperature of the system stays constant.Thermalrelates to heat, which is in turn related to temperature. Temperature is the average heat (movement) energy of the molecules in a substance.

Consider an ideal gas confined in a cylinder with a frictionless piston. The reversibleexpansion of gas takes place in a finite number of infinitesimally small intermediate steps. If the Pextis infinitesimally less than internalpressure of gas ‘P’ by ‘dP’. Then gas expands reversibly and piston moves through a distance ‘dl’.

Since dP is so small, for all practical purposes.

Pext. –Pgas =P.

One work done by gas in one infinitesimal step (dw) can be expressed as;

dw =P´dV.[w = P´DV]

dw= PdV.

If the gas expands from V1to V2during isothermalreversible expansion. The total amount of work done would be equal to

Process of separation of different constituents from petroleum is called refining.

Liquiefing gas means changing of the substances in gaseous states are changed into liquid state.

To liquefy gas we must-

<>Decrease temperature <>Increase pressure

By doing this the molecules of gas will come closer to each other and temperature is reduced so it will remove the enough energy to convert gas into liquid state. Thomas Andrews did work onliquefaction of gases like carbon dioxide.

An ore is a naturally occurring mineral or rock from which a valuable or useful substance, especially a metal, can be extracted at a reasonable cost.

Gangue is a worthless rock or mineral matter of no value occurring with the metallic ore in a vein or deposit.

Flux, in metallurgy, any substance introduced in the smelting of ores to promote fluidity and to remove objectionable impurities in the form of slag

Diffusion is the net movement of molecules or atoms from a region of high concentration to a region of low concentration

A diffusion is a process in physics. Some particles aredissolvedin a glass of water. At first, the particles are all near one top corner of the glass. If the particles randomly move around ("diffuse") in the water, they eventually become distributed randomly and uniformly from an area of high concentration to an area of low concentration, and organized (diffusion continues, but with no netflux).

Diffusion is the net movement of molecules or atoms from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in chemical potential of the diffusing species.

Diffusion is net movement of anything from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in concentration. The concept of diffusion is widely used in: physics, chemistry, biology, sociology, economics, and finance

option Bit doesn't depend on temperature and concentration of reactants

happy environment day

Lensmeter

generator's principle

generator's working

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options (2) matchstick should be correct as when we matchstick burns it turns from red to Black

Churning is the process of shaking up cream or whole milk to make butter, usually using a butter churn. In Europe from the Middle Ages until the Industrial Revolution, a churn was usually as simple as a barrel with a plunger in it, moved by hand.

Hess's law allows the enthalpy change (ΔH) for a reaction to be calculated even when it cannot be measured directly. This is accomplished by performing basic algebraic operations based on the chemical equations of reactions using previously determined values for the enthalpies of formation.

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Ans :- Most of thisair pollutionwecauseresults from the burning of fossil fuels, such as coal, oil, natural gas, and gasoline to produce electricity and power our vehicles. Carbon dioxide (CO2) is a good indicator of how much fossil fuel is burned and how much of otherpollutantsare emitted as a result.

Here are some simplesteps youcan take:

Avoidsmoking indoors (quitting smoking is the best answer for overall health)

Use craft supplies in well-ventilated areas.

Make sure your gas stove is well-ventilated.

Minimize clutter.

Remove carpeting if possible.

Use a dehumidifier and/orairconditioner toreduce moisture.

The standardenthalpy of formationor standardheat of formationof a compound is the change ofenthalpyduring theformationof 1 mole of the substance from its constituent elements, with all substances in their standard states. ... For an element: the form in which the element is most stable under 1 bar of pressure.

obtion b.

As the kinetic energy of the molecules increases, the number of molecules transitioning into a vapor also increases, thereby increasing the vapor pressure. The vapor pressure of any substance increases non-linearlywith temperature according to the Clausius–Clapeyron relation.

DEFINITION: HESS'S LAW

The heat of any reactionΔH∘fΔHf°for a specific reaction is equal to the sum of the heats of reaction for any set of reactions which in sum are equivalent to the overall reaction

Hess's Law of Constant Heat Summation(or justHess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes. This law is a manifestation that enthalpy is astate function.

Introduction

Hess's Law is named after Russian Chemist and Doctor Germain Hess. Hess helped formulate the early principles of thermochemistry. His most famous paper, which was published in 1840, included his law on thermochemistry. Hess's law is due to enthalpy being astate function, which allows us to calculate the overall change in enthalpy by simply summing up the changes for each step of the way, until product is formed. All steps have to proceed at the same temperature and the equations for the individual steps must balance out. The principle underlying Hess's law does not just apply to Enthalpy and can be used to calculate other state functions like changes inGibbs' EnergyandEntropy.

Fermentationis a metabolicprocessthat produces chemical changes in organic substrates through the action of enzymes. ... The science offermentationis known as zymology. In microorganisms,fermentationis the primary means of producing ATP by the degradation of organic nutrients anaerobically.

The carbon compounds, used as a fuel, have high calorific values. Therefore, carbon and its compounds are used as fuels for most applications. Most of the carbon compounds give a lot of heat and light when burnt in air. Saturated hydrocarbons burn with a clean flame and no smoke is produced.

The process in which a substanceloses an electronin a chemicalreactionis called oxidation. ... Oxidation is a combination of elements with oxygen. It's also areactionoflosing electronsandgainingpositive charge. The atoms thatlost electronsare said to be oxidized.

The reaction of Carbon and its compounds with oxygen is a highly exothermic process. The ignition temperature can be attained easily. These fuels are readily available and easy to use. Saturated hydrocarbons burn with a clean flame and do not produce smoke. They have high calorific values.

Two compounds which have different solubilities in a solvent S can be separated from each other by Fractional Crystallisation. The process involves a series of repeated-crystallisations. The mixture of the two compounds in the solvent S is heated so as to make it saturated. When the hot solution is allowed to cool, the less soluble substance crsytallises out first while the more soluble substance remains in the solution. The crystals of first compound are separated from the mother liquor and the mother liquor is again concentrated and allowed to cool when the crystals of the 2nd compound are obtained.

Option d is correct as all of the following are inflammable substances.

Mechanism of the Hell-Volhard-Zelinsky Reaction. Phosphorus reacts with bromine to give phosphorus tribromide, and in the first step this converts the carboxylic acid into an acyl bromide. An acyl bromide can readily exist in the enol form, and this tautomer is rapidly brominated at the α-carbon.