Answer:
Solution : Given,
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of Fe = 36.76 g
Mass of S = 21.11 g
Mass of O = 42.13 g
Step 1 : convert given masses into moles.
Moles of Fe =
Moles of S = \frac{\text{ given mass of S}}{\text{ molar mass of S}}= \frac{21.11g}{32g/mole}=0.65moles
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Moles of O = \frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{42.13g}{16g/mole}=2.63[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Fe =
For S =
For O =
The ratio of Fe : S : O= 1 : 1 : 4
Hence the empirical formula is
Answer : The volume of the cube submerged in the liquid is, 29.8 mL
Explanation :
First we have to determine the mass of ice.
Formula used :
Given:
Density of ice =
Volume of ice = 45.0 mL
The cube will float when 40.5 g of liquid is displaced.
Now we have to determine the volume of the cube is submerged in the liquid.
Thus, the volume of the cube submerged in the liquid is, 29.8 mL
Answer:
Explanation:
The chemical expression for the reaction between iron and oxygen is:
4Fe(s) + 3O₂ (g) 2Fe₂O₃ (s)
The number of moles of Fe = mass of Fe/ molecular mass of Fe
The number of moles of Fe = 56 g/ 55.845 g/mol
The number of moles of Fe = 1.002 moles of Fe
The number of moles of oxygen = mass of oxygen/ molecular mass of oxygen
The number of moles of oxygen = 156 g /32 g/mol
The number of moles of oxygen = 4.875 moles of oxygen
Assume that Fe is the limiting reactant, the number of Fe₂O₃ can be calculated as:
moles of Fe₂O₃ = 1.002 mole of Fe × 2 moles of Fe₂O₃/ 4 moles of Fe
moles of Fe₂O₃ = 0.501 mole of Fe₂O₃
Assume that O₂ is the limiting factor, the number of Fe₂O₃ is:
moles of Fe₂O₃ = 4.875 moles of O₂ × 2 moles of Fe₂O₃/ 3 moles of O₂
moles of Fe₂O₃ = 3.25 mole of Fe₂O₃
Thus, after the reaction is complete, Fe and O₂ contain different moles of Fe₂O₃. Only Fe gets consumed in the reaction and it is the limiting factor.