Iron(iii) oxide is formed when iron combines with oxygen in the air. how many moles of fe2o3 are formed when 55.8 g or fe reacts completely with oxygen? 4fe(s)+3o 2(g) --> 2fe2o3(s) a. 0.25 mol b. 0. 50 mol c. o. 75 mol d. 1.00 mol

The correct answer is Option B.

Explanation:

To calculate the number of moles, we use the formula:

Molar mass of iron = 55.8 g/mol

Given mass of iron = 558.8

Putting values in above equation, we get:

For the given chemical equation:

By Stoichiometry,

4 moles of Iron produces 2 moles of Iron(III) oxide

So, 1 mole of Ion will produce = = 0.5 mole of Iron (III) oxide.

Hence, the correct answer is Option B.

(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