I burned a candle for 3 minutes. It started with a mass of 38.53g (C25H52). It ended with a mass of 38.48g. What mass of water was produced in three minutes? If I burned the candle all day, what mass of the candle would react?
38.53-38.48 = 0.05 gram of C25H52 that burned.
Convert 0.05 g C25H52 to moles. Moles = grams/molar mass.
Using the coefficients in the balanced equation, convert moles C25H52 to moles H2O.
Convert moles H2O to grams. grams = moles x molar mass.
would the answer for the first question be .06654 g H2O?
I obtained 0.065 g but I think we're allowed only one sig figure.
What would be the answer to the second question then?
To find the mass of water produced, we need to calculate the difference in mass of the candle before and after burning.
The initial mass of the candle is 38.53g, and the final mass is 38.48g. The difference in mass is:
38.53g - 38.48g = 0.05g
This means that 0.05g of the candle was consumed during combustion.
To calculate the mass of water produced, we need to use the balanced chemical equation for the combustion of C25H52 (candle wax):
C25H52 + 38O2 → 25CO2 + 26H2O
From the equation, we can see that for every 1 mole of C25H52 burned, it produces 26 moles of water (H2O). To convert the mass of the candle consumed to moles, we need to determine the molar mass of C25H52.
The molar mass of C25H52 can be calculated by multiplying the atomic masses of carbon (C) and hydrogen (H) and summing them up. The atomic mass of C is approximately 12.01 g/mol, and the atomic mass of H is approximately 1.01 g/mol.
Molar mass of C25H52 = (12.01 g/mol * 25) + (1.01 g/mol * 52) = 300.25 g/mol + 52.52 g/mol = 352.77 g/mol
Now, using the molar mass of C25H52 and the mass consumed (0.05g), we can calculate the number of moles of C25H52 burned:
moles of C25H52 = mass consumed / molar mass = 0.05g / 352.77 g/mol
Next, we can use the mole ratio from the balanced equation to determine the moles of water produced:
moles of H2O produced = moles of C25H52 * (26 moles of H2O / 1 mole of C25H52)
Now, to calculate the mass of water produced, we can multiply the moles of water produced by the molar mass of water (approximately 18.02 g/mol):
mass of water produced = moles of H2O produced * molar mass of H2O = moles of H2O produced * 18.02 g/mol
For the first three minutes, the mass of water produced can be calculated using the above equations.
However, to determine the mass of the candle that would react if burned all day, we need to know the burn rate (mass loss per unit time) of the candle. This information is required to estimate the total mass of the candle that would be consumed in a day.
Without the burn rate, we cannot determine the exact mass of the candle that would react.