A sheet of aluminum foil has a total area of 1.000 m2 and a mass of 3.636 g. What is the thickness of the sheet in millimeters?
1 answer:
Answer:
Explanation:
Given that,
Area of sheet of Aluminium foil is 1 m²
Mass of the sheet = 3.636 g
The density of Aluminium,
We need to find the thickness of the sheet in millimeters.
The density of an object is given in terms of its mass and volume as follows :
V = volume, V = A×t, t = thickness of the sheet
So,
Since, 1 cm = 10 mm
So,
t = 0.00134 mm
or
You might be interested in
We have the next % composition:
C. 49.48%
H, 5.19%.
N. 28.85%
0. 16.48%
We assume 100 g of sample
1) As we have 100 g of sample of Caffeine, we calculate the mass of each element involved here.
C. 49.48 g
H, 5.19 g
N. 28.85 g
0. 16.48 g
2) We calculate the number of moles of each element (we need the mass per mole of each element)
For C) 12.01 g/mol
49.48 g x (1 mol/12.01 g) = 4.120 moles
For H) 1.007 g/mol
5.19 g x (1 mol/1.007 g) = 5.154 moles
For O) 15.99 g/mol
16.48 g x (1 mol/15.99 g) = 1.030 moles
For N) 14.00 g/mol
28.85 g x (1 mol/14.00 g) = 2.060 moles
3) We choose the smallest number from 2) and divide the rest of them by it.
For C) 4.120 moles/1.030 moles= 4
For H) 5.154 moles/1.030 moles= 5
For O) 1.030 moles/1.030 moles= 1
For N) 2.060 moles/1.030 moles= 2
4) The numbers in 3) represents the subindex from the empirical formula of caffeine:
5) We calculate the molar mass of our empirical formula, 97.06 g/mol.
We already have the molar mass of the molecular formula, so we proceed like this:
n= the molar mass of the molecular formula/the molar mass of the empirical formula
n = 194.19 g/mol/97.06 g/mol = 2 approx.
We use "n" and we multiply our empirical formula by n = 2:
Therefore, our molecular formula: