What is the coefficient of Oxygen in the balanced reaction below: __C2H4+ __O2--> CO2+ __H2O

The coefficient of Oxygen in the balanced reaction : 3

Given

Reaction(unbalanced)

C2H4+ O2--> CO2+H2O

Required

The coefficient of Oxygen

Solution

C₂H₄+ aO₂⇒ bCO₂+cH₂O

C, left=2, right=b⇒b=2

H, left=4, right=2c⇒2c=4⇒c=2

O, left=2a, right=2b+c⇒2a=2b+c⇒2a=2.2+2⇒2a=6⇒a=3

The equation becomes :

C₂H₄+ 3O₂⇒ 2CO₂+2H₂O

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g