Answer:
Pressure of the gas is greater than the vapor pressure, therefore all the solid will not sublime.
Explanation:
To solve this problem we use ideal gas equation.
PV =nRT
If Presure of the gas (P) is greater than vapor pressure (56.5 atm), all the solid will not sublime. But If P < 56.5 atm, all of it will sublime.
where;
P is pressure of the gas in atm
V is volume of gas in Litre
T is absolute temperature of the gas in Kelvin
n is number of gas moles
R is ideal gas constant or Boltzmann constant = 0.082057 L atm K⁻¹ mol⁻¹
Given T = 20 °C = 273 + 20 = 293K
Volume = 0.25L
n = Reacting mas (m)/Molar mass(M)
Molar mass of CO₂ = 12 + (16X2) = 12+32 = 44g/mol
Reacting mass = 10g
n = m/M ⇒ 10/44
n = 0.2273
PV =nRT ⇒ P = nRT/V
P = (0.2273X0.082057 X293)/0.25
P = 21.8596 atm
Therefore, since Pressure of the gas is greater than the vapor pressure, all the solid will not sublime.
8.6 cm
Explanation:
Step 1:
In this we have to find the focal length of converging lens.
To find focal length we have,

where u = Object distance
v= Image distance
f = Focal length
Step 2:

(1/f) = 0.116
f = 1/0.116
f = 8.6 cm
The closure temperature represents the point when isotopes are no longer free to move out of a crystal lattice.
Answer: Option C
<u>Explanation:</u>
The closure temperature can also be termed as blocking temperature. It is mostly used in radiometric dating. As the temperature decreases, below a certain point the isotopes may get freeze in their lattice positions. And there may be slowing of diffusion.
At the closure temperature, that rate of diffusion will be zero as the isotopes will be no longer free to move out of crystal lattice. So, this is termed as closure or blocking temperature. As the isotopes loose their ability to move, their concentration will remain fixed in their position leading to measurement of radiation dating.