Grams of Phosphorus = 4.14 grams
Grams of white compound = 27.8 grams
Grams of Chlorine would be = 27.8 - 4.14 = 23.66 grams
Calculating moles which would be grams / molar mass
Molar mass of P = 30.97 grams / moles; Molar mass of Cl = 35.45 grams / moles
Moles of Phosphorus = 4.14 grams / 30.97 grams / moles = 0.1337 moles
Moles of Chlorine = 23.66 grams / 35.45 grams / moles = 0.6674 moles
Calculating the ratios by dividing with the small entity
P = 0.1337 moles / 0.1337 moles = 1
Cl = 0.6674 moles / 0.1337 moles = 5
So the empirical formula would be PCl5
Answer:
Percentage lithium by mass in Lithium carbonate sample = 19.0%
Explanation:
Atomic mass of lithium = 7.0 g; atomic mass of Chlorine = 35.5 g; atomic mass of carbon = 12.0 g; atomic mass of oxygen = 16.0 g
Molar mass of lithium chloride, LiCl = 7 + 35.5 = 42.5 g
Percentage by mass of lithium in LiCl = (7/42.5) * 100% = 16.4 % aproximately 16%
Molar mass of lithium carbonate, Li₂CO₃ = 7 * 2 + 12 + 16 * 3 =74.0 g
Percentage by mass of lithium in Li₂CO₃ = (14/74) * 100% = 18.9 % approximately 19%
Mass of Lithium carbonate sample = 2 * 42.5 = 85.0 g
mass of lithium in 85.0 g Li₂CO₃ = 19% * 85.0 g = 16.15 g
Percentage by mass of lithium in 85.0 g Li₂CO₃ = (16.15/85.0) * 100 % = 19.0%
Percentage lithium by mass in Lithium carbonate sample = 19.0%
Answer:
1.387 moles
Explanation:
Step 1:
The balanced equation for the reaction. This is illustrated below:
4Fe + 3O2 —> 2Fe2O3
Step 2:
Determination of the number of mole of Fe in 155.321g of Fe. This can be achieved by doing the following:
Mass of Fe = 155.321g
Molar Mass of Fe = 56g/mol
Number of mole of Fe =?
Number of mole = Mass/Molar Mass
Number of mole of Fe = 155.321/56
Number of mole of Fe = 2.774 mol
Step 3:
Determination of the number of mole of rust (Fe2O3) produced. This is illustrated below:
From the balanced equation above,
4 moles of Fe produced 2 moles of Fe2O3.
Therefore, 2.774 moles of Fe will produce = (2.774 x 2)/4 = 1.387 moles of Fe2O3.
Therefore, 1.387 moles of rust (Fe2O3) is produced from the reaction
Answer:
I believe the answer is B.
Explanation:
I have never heard of it meaning the coldest point in outer space or freezing point of "pure" water at sea level. As for C, substances have a different points where the molecules stop moving. So the answer that makes the most sense is B.