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How many grams of 02 are needed to completely burn 26.2 g of C3H8

User Zorgbargle
by
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2 Answers

2 votes
Molar mass :

O2 = 31.99 g/mol

C3H8 = 44.09 g/mol

C3H8 + 5 O2 = 3 CO2 + 4 H2O

44.09 g ---------------- 5 x 31.99 g
26.2 g ----------------- ?? ( mass of O2)

26.2 x 5 x 31.99 / 44.09 =

4190.69 / 44.09 => 95.04 g of O2

hope this helps!


User Disper
by
7.8k points
5 votes

Answer:

We need 95.0 grams of O2

Step-by-step explanation:

Step 1 :Data given

Mass of C3H8 = 26.2 grams

Molar mass C3H8 = 44.1 g/mol

Step 2: The balanced equation

C3H8 + 5O2 → 3CO2 + 4H2O

Step 3: Calculate moles C3H8

Moles propane = mass / molar mass

Moles propane = 26.2 grams / 44.1 g/mol

Moles propane = 0.594 moles

Step 4: Calculate moles O2

For 1 mol propane we need 5 moles O2 to produce 3 moles CO2 and 4 moles H2O

For 0.594 moles propane we need 5*0.594 = 2.97 moles O2

Step 5: Calculate mass O2

Mass O2 = moles * molar mass

Mass O2 = 2.97 moles * 32.0 g/mol

Mass O2 = 95.0 grams

We need 95.0 grams of O2

User Dragos
by
7.7k points