The correct answer is the Tyndall effect. This is also known as the Tyndall scattering. It is the light scattering by the particles in a colloid or in a suspension. This phenomenon is used to determine size and density of particles in colloidal matter.
Answer: There are 
atoms of hydrogen are present in 40g of urea, 
.
Explanation:
Given: Mass of urea = 40 g
Number of moles is the mass of substance divided by its molar mass.
First, moles of urea (molar mass = 60 g/mol) are calculated as follows.
According to the mole concept, 1 mole of every substance contains 
atoms.
So, the number of atoms present in 0.67 moles are as follows.
In a molecule of urea there are 4 hydrogen atoms. Hence, number of hydrogen atoms present in 40 g of urea is as follows.
Thus, we can conclude that there are atoms of hydrogen are present in 40g of urea, .
Answer:
<em>Lower vapor pressures of a substance has an obvious effect on a</em> <em>boiling point</em>. <em>The</em> <em>freezing point </em><em>the rate at which the solid melts is equal to the rate which freezes. </em>
Explanation:
<em>In practice, small differences between these quantities can be observed. It is difficult, if not impossible, to heat a solid above its melting point because the heat </em>
<em />
<em>Hope this helps (: </em>
773.33 degrees F
F=Fahrenheit
K=Kelvin
F=K x 9/5 - 459.67
773.33 = 685 x 9/5 - 459.67
<span>Because
the early universe was so hot that even tough the conditions to
create heavy elements were there, they will break apart
immediately after their
formation because it was
too hot for the heavy elements to remain stable. It was only later
after the universe cold down that elements weren’t break apart and
the process of forming heavy elements could begin.</span>
