% Composition = ?
no atom in 2 g of styrene =?
molar mass of strene =104.15
% composition of c= 12/13.008 =.922*100=92.2
% composition of h =1.008/13.008=0.0774*100= 7.74
no gram atom=mass in kg /molar mass=2/104.15 =0.01920 mol
no of gram atom * avogadro's number = 0.0192*6.02 *10( exponent 23) =1.15584
Answer:
Explanation:
Information given about the element:
Number of protons = 74
Number of neutrons = 110
For the atomic number:
Neutral atoms such as this one would have their atomic number to be the same with their number of electrons and protons:
atomic number = number of protons = number of electrons
The atomic number would therefore be 74
For the mass number:
The mass of an atom is centrally concentrated within the tiny nucleus. The mass number is the sum of protons and neutrons in an atom. Protons and neutrons are nuclear particles and are called nucleons:
Mass number = number of protons + number of neutrons = 74+110=184
Is this a new element?
From the peroidic table, tungsten(W) perfectly fits this description of the atom. It has an atomic number of 74 and a mass number of approximately 184. The element is not a new element.
Is it solid, liquid, or gas?
The element is a hard metallic solid. It is a classified as a transition metal on the periodic table. Transition metals have very unique metals and are mostly solids.
Answer : The rate of change of the total pressure of the vessel is, 10.5 torr/min.
Explanation : Given,
![\frac{d[NO]}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BNO%5D%7D%7Bdt%7D)
=21 torr/min
The balanced chemical reaction is,
The rate of disappearance of 
= ![-\frac{1}{2}\frac{d[NO]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B2%7D%5Cfrac%7Bd%5BNO%5D%7D%7Bdt%7D)
The rate of disappearance of 
= ![-\frac{d[Cl_2]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BCl_2%5D%7D%7Bdt%7D)
The rate of formation of 
= ![\frac{1}{2}\frac{d[NOCl]}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%5Cfrac%7Bd%5BNOCl%5D%7D%7Bdt%7D)
As we know that,
=21 torr/min
So,
![-\frac{d[Cl_2]}{dt}=-\frac{1}{2}\frac{d[NO]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BCl_2%5D%7D%7Bdt%7D%3D-%5Cfrac%7B1%7D%7B2%7D%5Cfrac%7Bd%5BNO%5D%7D%7Bdt%7D)
![\frac{d[Cl_2]}{dt}=\frac{1}{2}\times 21torr/min=10.5torr/min](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BCl_2%5D%7D%7Bdt%7D%3D%5Cfrac%7B1%7D%7B2%7D%5Ctimes%2021torr%2Fmin%3D10.5torr%2Fmin)
And,
![\frac{1}{2}\frac{d[NOCl]}{dt}=\frac{1}{2}\frac{d[NO]}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%5Cfrac%7Bd%5BNOCl%5D%7D%7Bdt%7D%3D%5Cfrac%7B1%7D%7B2%7D%5Cfrac%7Bd%5BNO%5D%7D)
![\frac{d[NOCl]}{dt}=\frac{d[NO]}=21torr/min](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BNOCl%5D%7D%7Bdt%7D%3D%5Cfrac%7Bd%5BNO%5D%7D%3D21torr%2Fmin)
Now we have to calculate the rate change.
Rate change = Reactant rate - Product rate
Rate change = (21 + 10.5) - 21 = 10.5 torr/min
Therefore, the rate of change of the total pressure of the vessel is, 10.5 torr/min.
Rutherford's atomic structure model was revolutionary. Contrary to J.J. Thompson's "plum pudding" model (which consisted of a solid, even mixture of protons and electrons), Rutherford's model consisted of one small, positively charged, dense nucleus, a layer of empty space, and a layer of negatively charged electrons. He came to this conclusion through his gold-foil experiment. He shot a ray of alpha particles towards the thin gold foil, and to Rutherford's surprise, some of the rays reflected back instead of going straight through the foil as he originally thought.
