Estimate the enthalpy change (J/g) for air being heated from 250 C to 350 C. At 300 K the specific heat at constant pressure, cp, is 1.005 J/g/K and this value does not change much for temperatures surrounding 300K. Give 1 decimal in your answer.

The enthalpy change is 10.1 J/g.

Explanation:

∆H = Cp(T2 - T1)

∆H is the enthalpy change of air

T2 is the final temperature of air = 35 °C = 35+273 = 308 K

T1 is the initial temperature of air 25 °C = 25+273 = 298 K

Cp is the specific heat at constant pressure at and surrounding 300 K (T2 and T1 surrounds 300 K) = 1.005 J/gK

∆H = 1.005(308 - 298) = 1.005×10 = 10.05 = 10.1 J/g

∆H = 10.1 J/g (in one decimal place)

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.