Answer:
The answer to your questions is Cm = 25.5 J/mol°C
Explanation:
Data
Heat capacity = 0.390 J/g°C
Molar heat capacity = ?
Process
1.- Look for the atomic number of Zinc
Z = 65.4 g/mol
2.- Convert heat capacity to molar heat capacity
(0.390 J/g°C)(65.4 g/mol)
- Simplify and result
Cm = 25.5 J/mol°C
11.2L/22.4L (STP value) x 1 mol of CH4 x 16.04 g of CH4 = 8.2 g
<span>Let's assume
that the F</span>₂ gas has ideal gas behavior.
<span>
Then we can use ideal gas formula,
PV = nRT
Where, P is the pressure of the gas (Pa), V is the volume of the gas
(m³), n is the number of moles of gas (mol), R is the universal gas
constant ( 8.314 J mol</span>⁻¹ K⁻<span>¹) and T is temperature in Kelvin.</span>
Moles = mass / molar mass
Molar mass of F₂ = 38 g/mol
Mass of F₂ = 76 g
Hence, moles of F₂ = 76 g / 38 g/mol = 2 mol
<span>
P = ?
V = 1.5 L = 1.5 x 10</span>⁻³ m³
n = 2 mol
R = 8.314 J mol⁻¹ K⁻<span>¹
T = -37 °C = 236 K
By substitution,
</span>
P x 1.5 x 10⁻³ m³ = 2 mol x 8.314 J mol⁻¹ K⁻¹ x 236 K
p = 2616138.67 Pa
p = 25.8 atm = 26 atm
Hence, the pressure of the gas is 26 atm.
Answer is "a".
<span>
</span>
Explanation:
Half life is simply the amount of time it takes for half of a substance to decompose.
Options;
- Carbon-14 has a half-life of 5,730 years. A 30 gram sample will be 10 grams after 5,730 years. This is incorrect. After 5730 years, 15g of the sample ought to remain.
- Nickel-59 has a half-life of 76,000 years. A sample would go through 3 half-lives in 228,000 years. This is correct. 3 * 76000 = 228,000
- Hafnium-182 has a half-life of 9 million years. A 38 gram sample would be 4.75 grams in 27 million years. This is incorrect. Mass after 3 half lives (27/9) = 9.5 (38 / 2 / 2)
- Iron-60 has a half-life of 1.5 million years. In 6 million years a 40 gram sample would be reduced to 10 grams. This is incorrect. Mass after 4 half lives (6 / 1.5) = 2.5 gram (40 / 2 / 2 /2 / 2)
- Lead-202 has a half-life of 52,500 years. The original sample must have been 120 grams if you have a 60 gram sample after 105,000 years. This is incorrect. Original sampe = 240 gram. So after 2 half lives (105,000/52500), mass left = 60 (240 / 2 /2)
Explanation:
For AX type ceramic material, the number of formula per unit cells is as follows.
or, 
where, n' = no. of formula units per cell
= molecular weight of cation = 90.5 g/mol
= molecular weight of anion = 37.3 g/mol
= volume of cubic cell = 3.55 
a = edge length of unit cell = 
= Avogadro's number = 
= density = 3.55
Now, putting the given values into the above formula as follows.
= 
= 0.9
= 1 (approx)
Therefore, we can conclude that out of the given options crystal structure of cesium chloride is possible for this material.
