We are provided with the amount of energy released when one mole of carbon reacts. We mus first convert the given mass of carbon to moles and then compute the energy released for the given amount.
Moles = mass / atomic mass
Moles = 23.5 / 12
Moles = 1.96 moles
One mole releases 394 kJ/mol
1.96 moles will release:
394*1.96
= 772.24
The enthalpy change of the reaction will be -772.24 kJ
Answer:
The correct answer will be "4.60 g".
Explanation:
The given values are:
Volume of Butane = 7.96 mL
Density = 0.579 g/mL
As we know,
⇒ 
On putting the estimated values, we get
⇒ 
⇒ 
Answer:
2666.7 hours
Explanation:
The key to solve this problem is that we are given the propane gas consumed in one hour by giving us the information of the volume consumed at 1 atm, 298 K (25 +273). Using the gas law we can calculate the rate of consumption of propane per hour, and from here we can calculate its mass and converting it to gallons and finally diving the 400 gallos by this number.
PV = nRT ∴ n = PV/RT
n = 1 atm x 165 L/ (0.08206 Latm/kmol x 298 K ) = 6.75 mol propane
Mass propane :
6.75 mol x 44 g/mol = 296.88 g
convert this to Kg:
296.88 g/ 1000 g/Kg = 0.30 Kg
calculate the volume in liters this represents by dividing by the density:
0.30 Kg / 0.5077 Kg/L = 0.59 L
changing this to gallons
0.59 L x 1 gallon/3.785 L = 0.15 gallon
and finally calculate how many hours the 400 gallons propane tank will deliver
400 gallon/ 0.15 gallon/hr = 2666.7 hr