Explanation:
<u>Moles is denoted by given mass divided by the molecular mass , </u>
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
For example ,
For a compound X ,
The given mass i.e. w = 20 g
and the molecular mass ,i.e. , m = 10 g / mol
Then the moles can easily be calculated by using the above formula ,
n = w / m
n = 20 g / 10 g/mol = 2 mol
Hence , answer = 2 mol.
Charged particles or ionic particles?
# of atoms per mol = Avogadro’s # (6.022 x 10^23)
Number of mols = mass of substance / molar mass
73 g / 40.08 g = 1.8 mols of Ca in 73 grams
1.8 mols x avagadro’s # = 1.1 x 10^24 atoms in 73 grams of Ca
Answer:
The mass of silicon in kilograms in Earth's crust is
.
Explanation:
Mass of Earth =
(1 ton= 2000 lb)
(1 lb =453.6 g)
1 ton = 2000 × 453.6 g =907,200 g
Mass of Earth =
Percentage of earth crust = 0.50%
Mass of earth crust = M
Percentage of the silicon in Earth's crust = 27.2 %
Mass of silicon in in Earth's crust = m
1000 g = 1 kg
The mass of silicon in kilograms in Earth's crust is.
Answer: A. The free-moving electrons transmit heat quickly.
Explanation:
