Answer:
The density of Lithium β is 0.5798 g/cm³
Explanation:
For a face centered cubic (FCC) structure, there are total number of 4 atoms in the unit cell.
we need to calculate the mass of these atoms because density is mass per unit volume.
Atomic mass of Lithium is 6.94 g/mol
Then we calculate the mass of four atoms;

⇒next, we estimate the volume of the unit cell in cubic centimeter
given the edge length or lattice constant a = 0.43nm
a = 0.43nm = 0.43 X 10⁻⁹ m = 0.43 X 10⁻⁹ X 10² cm = 4.3 X 10⁻⁸cm
Volume of the unit cell = a³ = (4.3 X 10⁻⁸cm)³ = 7.9507 X 10⁻²³ cm³
⇒Finally, we calculate the density of Lithium β
Density = mass/volume
Density = (4.6097 X 10⁻²³ g)/(7.9507 X 10⁻²³ cm³)
Density = 0.5798 g/cm³
but heres a way to solve it
An athlete takes a deep breath, inhaling 1.85 L of air at 21°C and 754 mm Hg.
T
How many moles of air are in the breath? How many molecules?
Gas constant, R= 8.314 J mol ¹ K-1
PV = nRT
PV
RT
h=
=
P
= 0.08206 L atm mol-1 K-1
= 62.36 L Torr mol-1 K-1 -
1 atm = 760 mm Hg = 760 Torr
754 Forr 1.85€
6236 Jerr 294K
Answer:
A. R represents chemical energy; P represents thermal energy.
Step-by-step explanation:
The molecules in the gas contain chemical energy (R).
When the gas burns, the chemical energy is released as heat, or thermal energy (P).
The answer is letter C. hydrogen bonds. Surface tension in water, which makes water form drops and causes the surface to form a curve above the mouth of a container, results from the water molecules being strongly held by H bonds to those water molecules beside and beneath them. The cohesion among water molecules and the adhesion of water to other materials like rock and soil make capillarity possible.