Calculate the concentrations of H3O+ and OH- ions in a 0.050 M Ba(OH)2 solution. a. [H3O+ ] = 0.050 M, [OH- ] = 0.050 M b. [H3O+ ] = 1.0 ´ 10-7 M, [OH- ] = 0.10 M c. [H3O+ ] = 2.0 ´ 10-13 M, [OH- ] = 0.050 M d. [H3O+ ] = 1.0 ´ 10-13 M, [OH- ] = 0.10 M e. [H3O+ ] = 0.10 M, [OH- ] = 1.0 ´ 10-13 M

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied