Answer:
Carbon dioxide
Explanation:
Neither helium nor carbon dioxide has a molecular dipole, so their strongest van der Waals attractive forces are London forces.
Helium is a small spherical atom with only a two electrons, so its atoms have quite weak attractions to each other.
CO₂ is a large linear molecule. It has more electrons than helium, so the attractive forces are greater. Furthermore, the molecules can align themselves compactly side-by-side and maximize the attractions (see below).
For example. CO₂ becomes a solid at -78 °C, but helium must be cooled to -272 °C to make it freeze (that's just 1 °C above absolute zero).
Answer: Equilibrium constant for this reaction is
.
Explanation:
Chemical reaction equation for the formation of nickel cyanide complex is as follows.
We know that,
K =
We are given that,
and,
Hence, we will calculate the value of K as follows.
K =
K = 
= 
Thus, we can conclude that equilibrium constant for this reaction is
.
Answer:
b) The molecule has a molecular weight under 200 g/mole
Explanation:
The molecule has a molecular weight under 200 g/mole is the primary requirement for a molecule to be analyzed by Gas Chromatography.
Answer: The sample that contains the greater number of molecules is water.
Explanation: To calculate the number of molecules, it is used the Avogadro's number (
particles/molecules). So, considering that the mass to water and carbon dioxide is 1g (it can be any other number), the relationship between moles and molar weight is:

To water:
= 0.05 moles.
Therefore,
1 mol ----
molecules
0.05 moles ---- x
x =
molecules of water.
To carbon dioxide:
= 0.02 moles.
Therefore,
1 mol ----
molecules
0.02 moles ---- y
y =
molecules of carbon dioxide.