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

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

c is the answer because when something is left after something evaporates that shows the chemical change.