Answer:
The percent yield of this reaction is 70%
Explanation:
The reaction is: N₂ + 3H₂ → 2NH₃
We only have the mass of H₂, so we assume that N₂ is in excess
We convert the mass to moles, to work with the reaction:
450 g . 1mol / 2 g = 225 moles
Ratio is 2:3. 3 moles of H₂ can produce 2 moles of ammonia
Therefore 225 moles of H₂ will produce (225 .2)/ 3 = 150 moles
This is the 100% yield reaction → We convert the moles of NH₃ to mass
150 mol . 17g /1mol = 2550 g
Percent yield = (Produced yield/Theoretical yield) .100
Percent yield = (1575g/2550g) . 100 = 70%
Answer:
0.74 grams of methane
Explanation:
The balanced equation of the combustion reaction of methane with oxygen is:
it is clear that 1 mol of CH₄ reacts with 2 mol of O₂.
firstly, we need to calculate the number of moles of both
for CH₄:
number of moles = mass / molar mass = (3.00 g) / (16.00 g/mol) = 0.1875 mol.
for O₂:
number of moles = mass / molar mass = (9.00 g) / (32.00 g/mol) = 0.2812 mol.
- it is clear that O₂ is the limiting reactant and methane will leftover.
using cross multiplication
1 mol of CH₄ needs → 2 mol of O₂
??? mol of CH₄ needs → 0.2812 mol of O₂
∴ the number of mol of CH₄ needed = (0.2812 * 1) / 2 = 0.1406 mol
so 0.14 mol will react and the remaining CH₄
mol of CH₄ left over = 0.1875 -0.1406 = 0.0469 mol
now we convert moles into grams
mass of CH₄ left over = no. of mol of CH₄ left over * molar mass
= 0.0469 mol * 16 g/mol = 0.7504 g
So, the right choice is 0.74 grams of methane
Answer:
PV=nRT
n = PV/RT
n = m/Mm
m/Mm = PV/RT
m = MmPV/RT
T in kelvin = T Celsius + 273.15 = 293.15 K
m = (26.04 x 1.39 x 55)/(0.08206 x 293.15)
mass in grams = 82.8 grams
Explanation:
Ideal gases formula is PV=nRT, where:
P is the pressure (1.39 atm in this case)
V is the volume (55.0 L in this case)
R is the gas constant (0.08206 L.atm/K.mole)
T is the temperature (20.0C) should be converted to Kelvin
all the unit should correspond to the one in the R.
we also know that to find the mass, we can use number mole with the formula number of mole(n) = mass (m) divided by the molar mass (Mm). therefore we substituted that in the formula and make (m) the subject of the formula.
we found the mass to be 82.8 grams
Answer: Aluminum, 
Explanation:
Density is defined as the mass contained per unit volume. It is characteristic of a substance.
Given : Mass of object = 8.44 grams
Volume of object=
Putting in the values we get:
Thus density of the object will be which matches that of aluminium.
