calcium phosphate reacts with aqueous nitric acid to produce phosphoric acid and calcium nitrate Ca3(PO4) 2+6HNO3-2H2PO4+3Xa(NO3)2. (1) a 7.26g sample of calcium phosphate reacted completely when added to an excess of aqueous nitric acid to form 38.0cm3 of solution. Calculate the concentration in moldm^-3 of phosphoric acid in this solution.

(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