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Data: 1 nm = 1.10^9m; Speed of light = 3.00.10^8 m.s^-1; Planck\'s constant = 6.

ID: 953985 • Letter: D

Question

Data: 1 nm = 1.10^9m; Speed of light = 3.00.10^8 m.s^-1; Planck's constant = 6.626 10^-3 J-s; Avogadro's number = 6.02.10^23 mol^-1; Mass of electron = 9.11.10^-31 kg 1. A system does 125 J of work on its surroundings. Then the system absorbs 450 J of heat from the surroundings. Next, the surroundings absorb 365 J of heat from the system. Finally, 260 J of work is done by the surroundings on the system. The total change in the internal energy of the system is J. 2. Gasoline is burned in a cylinder equipped with a piston. The initial volume of the cylinder is 5.690.10^-4 m^3 and the final volume is 6.259 10^-3 m^3. The piston expands against a pressure of 1.207-10 Pa. The amount of work done (as applies to the system) is J. 3. The decomposition of liquid hydrogen peroxide into liquid water and oxygen gas can be represented by the following equation: 2 H_2O_(1) rightarrow 2 H_2O(l) + O_2(g) DeltaHdegree = -196.1 kJ The amount of heat absorbed or released when a mass of 652 g of liquid hydrogen peroxide decomposes at a constant pressure according to this equation is:

Explanation / Answer

2)

we know that

for a constant pressure process

work done = P x (V2 - V1)

given

Pressure (P) = 1.207 x 10^6 Pa

V1 = 5.69 x 10-4 m3

V2 = 6.259 x 10-3

so

Work done (W) = 1.207 x 10^6 x ( 6.259 x 10-3 - 5.69 x 10-4)

W = 6867.83

so

amount of work done is 6867.83 J