<span>0.310 moles
First, look up the atomic weights of the elements involved.
Atomic weight carbon = 12.0107
Atomic weight hydrogen = 1.00794
Atomic weight sulfur = 32.065
Molar mass (C3H5)2S = 6 * 12.0107 + 10 * 1.00794 + 32.065
= 114.2086 g/mol
Moles (C3H5)2S = 35.4 g / 114.2086 g/mol = 0.309959145 mol
Since there's just one sulfur atom per (C3H5)2S molecule, the number of moles of sulfur will match the number of moles of (C3H5)2S which is 0.310 when rounded to 3 significant digits.</span>
Answer:
Kinetic energy: 
Velocity: 
Explanation:
From the equations of the photo-electric effect,
We know:
Where,
1.
is the Planck's constant which is 
2.
are the frequency of light emitted and threshold frequencies respectively.
3.
is the kinetic energy of the electrons emitted.
By fact, we come to know that the threshold frequency of Zn is 300nm
And also 
Where ,
1. 
is the speed of light 
2.
is the wavelength.
Thus,
Now to find velocity:
