Answer:
Density of unit cell ( rhodium) = 12.279 g/cm³
Explanation:
Given that:
The radius (r) of a rhodium atom = 135 pm
The atomic mass of rhodium = 102.90 amu
For a face-centered cubic unit cell,
where;
a = edge length.
Making "a" the subject of the formula:
a = 381.8 pm
to cm, we get:
a = 381.8 × 10⁻¹⁰ cm
However, recall that:
where;
mass of unit cell = mass of atom × numbers of atoms per unit cell
Also;
Recall also that number of atoms in a unit cell for a face-centered cubic = 4
So;
mass of unit cell = 6.83380375 × 10⁻²² g
Density of unit cell ( rhodium) = 12.279 g/cm³
Answer: Out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
Explanation:
A change that leads to the change in chemical composition of a substance is called a chemical change.
For example, 
Here, bond between the reactant atoms nitrogen and hydrogen is broken down.
On the other hand, bond connecting the products that is 
and 
is formed.
Thus,, we can conclude that out of the given options bonds connecting atoms in reactants break, and bonds connecting atoms in products form are the changes which takes place when a chemical change occurs.
Frequency = speed of light/ wavelength of photon. wavelength = speed of light/frequency = 3 x 10^8 / 2.43 x 10^8= 1.23m
