1. Which of the following does NOT have an electron configuration ending with 3s2 3p6?

a) Cl- (chloride)

b) S2- (sulfide)

c) Al3+ (aluminum ion)

d) Ca2+ (calcium ion)

2. A complete electron configuration is given as: 1s2 2s2 2p6 3s2 3p6. What are 2 DIFFERENT (not the same element) atomic entities that could both have this configuration? Explain using complete sentences.

3. A complete electron configuration is given as: 1s2 2s2 2p5 3s1. Is this configuration possible? Explain using complete sentences AND an electron configuration diagram (upload image into answer).

(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