Answer:
1040%
Explanation:
To solve this question we must convert the mass of Iron to moles in order to find limiting reactant. With limiting reactant we can find the theoretical moles of hydrogen and theoretical mass:
Percent yield = Actual yield (5.40g) / Theoretical yield * 100
<em>Moles Fe -Molar mass: 55.845g/mol-:</em>
10.3g * (1mol / 55.845g) = 0.184 moles of Fe will react.
For a complete reaction of these moles there are necessaries:
0.184 moles Fe* ( 3 mol H2SO4 / 2 mol Fe) = 0.277 moles H2SO4.
As there are 14.8 moles of the acid, <em>Fe is limiting reasctant.</em>
The moles of H2 produced are:
0.184 moles Fe* ( 3 mol H2 / 2 mol Fe) = 0.277 moles H2
The mass is:
0.277 moles H2 * (2.016g/mol) = 0.558g H2
Percent yield is:
5.40g / 0.558g * 100 = 1040%
It is possible the experiment wasn't performed correctly
Remember that:
number of moles = mass/molar mass
First, we get the molar mass of the nitrogen gas molecule:
It is known the the nitrogen gas is composed of two nitrogen atoms, each with molar mass 14 gm (from the periodic table)
Therefore, molar mass of nitrogen gas = 14 x 2 = 28 gm
Second we calculate the mass of the precipitate:
we have number of moles = 0.03 moles (given)
and molar mass = 28 gm (calculated)
Using the equation mentioned before,
mass = number of moles x molar mass = 0.03 x 28 = 0.84 gm
Empirical formula is calculated as follows
calculate the moles of each element, that is % composition/ molar mass
molar masses ( Si= 28.09g/mol , Cl= 35.5 g/mol, I=126.9 g/mol)
moles of silicon = 7.962/28.09g/mol= 0.283 moles
moles of chlorine = 20.10 / 35.5g/mol = 0.566 moles
moles of iodine= 71.94 / 126.9 g/mol= 0.567 moles
divide each mole with smallest mole (0.283)
that is silicon = 0.283/0.283= 1 mole
chlorine = 0.566/0.283= 2 mole
Iodine= o.567/0.283= 2 moles
empirical formula is therefore= SiCl2I2
Answer:
C. 3 and 4
Explanation:
Count H's in formula (each has 4)
- Hope that helped! Please let me know if you need a further explanation.
Answer:
The great confrontation between the two men occurred in 1686 when Newton published the first volume of his Principia and Hooke affirmed that it was he who had given him the notion that led him to the law of universal gravitation. Hooke demanded credit as the author of the idea but Newton denied it
Explanation:
