Answer:
8 Silicon atom are present in unit cell.
16 oxygen atoms are present unit cell.
Explanation:
Number of atoms in unit cell = Z =?
Density of silica = tex]2.32 g/cm^3[/tex]
Edge length of cubic unit cell = a = 0.700 nm = 
Molar mass of Silica = 
Formula used :
where,
= density
Z = number of atom in unit cell
M = atomic mass
= Avogadro's number
a = edge length of unit cell
On substituting all the given values , we will get the value of 'a'.
1 silicon is 2 oxygen atoms. then 8 silicon atoms will be 16 oxygen atoms.
The new volume is 330.2 ml
<u><em>calculation</em></u>
The new volume is calculated using the Charles law formula
that is V1/T1= V2/T2
where T1= 25.0 c into kelvin = 25 +273 = 298 K
V1= 300.0 ml
T2 = 55.0 c into kelvin = 273 +55 =328 K
V2 = ? ml
make V2 the subject of the formula by multiplying both side by T2
V2= V1T2/ T1
V2 =[ (300.0 ml x 328 k) / 298 k} = 330.2 ml
Answer : The mole fraction of nitrogen will be 0.4615.
Explanation : When nitrogen (
)and hydrogen (
)are mixed, the mole ratio becomes 1 : 1.5,
Now we know that () is acting as a limiting agent.
So at the time of when 0.4 moles of (
) is been formed it requires 0.4 moles of () and 3.4 moles of ()
So, we find the the remaining () will be 0.6 and
() will be 0.3 mole present in mixture.
So, the mole fraction of () becomes = 0.6 / (0.6 + 0.4 + 0.3) Which becomes = 0.4615
<span>When an ice cube is placed on a kitchen counter, heat will flow from the ice cube to the counter, causing the molecules in the counter to move more slowly. The molecules of the counter move more slowly because the heat transferred to them from the ice has reduced their kinetic energy.</span>
Answer:2.86x10^-7m
Explanation:E=hc/^
E=6.94x10^-19J
c = 2.9979x10^8m/s
h= 6.626x10^-34Js
^ =( 6.626x10^-34)x( 2.9979x 10^8)/ 6.94x10^-19
= 2.86x10^-7m
