Answer:
the atomic packing factor of Sn is 0.24
Explanation:
a = b = 5.83A and c = 3.18A.
Volume of unit cell = a²c
= (5.83)² * 3.18 * 10⁻²⁴ cm³
= 1.08 * 10⁻²²cm³
Volume of atoms =
![2 \times \frac{4}{3} \pi r^3](https://tex.z-dn.net/?f=2%20%5Ctimes%20%20%5Cfrac%7B4%7D%7B3%7D%20%5Cpi%20r%5E3)
(∴ BCC, effective number of atom is 2)
Volume of atoms =
![2 * \frac{4}{3} *3.14*(0.145*10^-^7cm)^3](https://tex.z-dn.net/?f=2%20%2A%20%5Cfrac%7B4%7D%7B3%7D%20%2A3.14%2A%280.145%2A10%5E-%5E7cm%29%5E3)
= 2.55*10⁻²³cm³
![\text {Atomic packing factor}=\frac{\text {volume occupied by atom}}{\text {volume of unit cell }}](https://tex.z-dn.net/?f=%5Ctext%20%7BAtomic%20packing%20factor%7D%3D%5Cfrac%7B%5Ctext%20%7Bvolume%20occupied%20by%20atom%7D%7D%7B%5Ctext%20%7Bvolume%20of%20unit%20cell%20%7D%7D)
![=\frac{2.55*10^-^2^3}{1.08*10^-^2^2} \\\\=0.24](https://tex.z-dn.net/?f=%3D%5Cfrac%7B2.55%2A10%5E-%5E2%5E3%7D%7B1.08%2A10%5E-%5E2%5E2%7D%20%5C%5C%5C%5C%3D0.24)
<h3>therefore, the atomic packing factor of Sn is 0.24</h3>
The correct answer is B.
1 mol O2 x 15.999 O2/ 1 mol O2 = 15.999 O2
16 O2 when rounded.
Answer:
The heat of combustion for the unknown hydrocarbon is -29.87 kJ/mol
Explanation:
Heat capacity of the bomb calorimeter = C = 1.229 kJ/°C
Change in temperature of the bomb calorimeter = ΔT = 2.19°C
Heat absorbed by bomb calorimeter = Q
![Q=C\times \Delta T](https://tex.z-dn.net/?f=Q%3DC%5Ctimes%20%5CDelta%20T)
![Q=1.229 kJ/^oC\times 2.19^oC=2,692 kJ](https://tex.z-dn.net/?f=Q%3D1.229%20kJ%2F%5EoC%5Ctimes%202.19%5EoC%3D2%2C692%20kJ)
Moles of hydrocarbon burned in calorimeter = 0.0901 mol
Heat released on combustion = Q' = -Q = -2,692 kJ
The heat of combustion for the unknown hydrocarbon :
![\frac{Q'}{0.090 mol}=\frac{-2,692 kJ}{0.0901 mol}=-29.87 kJ/mol](https://tex.z-dn.net/?f=%5Cfrac%7BQ%27%7D%7B0.090%20mol%7D%3D%5Cfrac%7B-2%2C692%20kJ%7D%7B0.0901%20mol%7D%3D-29.87%20kJ%2Fmol)
Answer:
99.3%
Explanation:
The percent by mass of the solute can be expressed as:
- % mass =
* 100%
And for this problem:
- Mass of Solute = Mass of sodium lithium chloride = 29 g
- Mass of Solvent = Mass of Water
So to calculate the percent by mass first we need to <u>calculate the mass of water</u>, to do so we use its<em> density</em> (1 g/L):
- 202 mL is equal to (202/1000) 0.202 L.
Density water = mass water / volume
- 1 g/L = mass water / 0.202 L
Now we have all the data required to <u>calculate the % mass:</u>
- % mass =
* 100 % = 99.3%