The first law of thermodynamics is only
First low of thermodynamics is also known as Law of conservation of mass and energy.
Practice free NEET NEET multiple-choice questions online with instant answers and detailed explanations. No login required.
The first law of thermodynamics is only
First low of thermodynamics is also known as Law of conservation of mass and energy.
A mixture of two moles of carbon monoxide and one mole of oxygen, in a closed vessel is ignited to convert the carbon monoxide to carbon dioxide. If ΔH is the enthalpy change and ΔE is the change in internal energy, then [KCET 2005]
Formation of CO2 from CO is an exothermic reaction; heat is evolved from the system, i.e., energy is lowered. Thus, exothermic reactions occur spontaneously on account of decrease in enthapy of system. Thus, ΔE > ΔH.
The relation between ΔE and ΔH is [MP PET 1992; MP PMT 1996; MP PET/PMT 1998]
ΔH = ΔE + PΔV.
At constant T and P, which one of the following statements is correct for the reaction, [AIIMS 1982, 83; KCET 1988; BHU 1995; MP PET 1997, 99]
, As is negative, thus ΔH < ΔE.
For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, ΔU and w correspond to [AIIMS 2005]
Bomb calorimeter is commonly used to find the heat of combustion of organic substances which consists of a sealed combustion chamber, called a bomb. If a process is run in a sealed container then no expansion or compression is allowed, so w = 0 and ∆U = q.
∆U < 0, w = 0
If ΔH is the change in enthalpy and ΔE the change in internal energy accompanying a gaseous reaction [KCET 1989; CBSE PMT 1990]
If Δn = –ve than ΔH < ΔE.
Enthalpy for the reaction C + O2 → CO2 is [DPMT 1987, 91]
It is a combustion reaction, ΔH = –ve.
The work done in ergs for the reversible expansion of one mole of an ideal gas from a volume of 10 litres to 20 litres at 25°C is
.
In a reversible isothermal process, the change in internal energy is
ΔE = 0 for reversible isothermal process.
The enthalpy of neutralization of which of the following acids and bases is nearly –13.6 Kcal [Roorkee 1999]
Heat of neutralisation of a strong acid and strong base is equal to –13.7 kcal.
Ready to ace NEET?
Free access · No credit card required
Yes. You can attempt every NEET question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.
No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.
The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.