Answer:
Atom is the smallest particle of matter.
Elements are made up of same atoms.
Atom consist of electron, proton and neutron.
Explanation:
Atom was first discovered by John Dalton.
word "Atom" came from Greek word, that means something that could not split. he explained that atom is indivisible particle.
In the end of 18th century J.J. Thomson put forward a new concept of atom. he said that atom have negative charged particles called electrons but overall atom is neutral.
In 1909 Rutherford with his students discovered positive charged particles and nucleus and said that it is in the center of atom.
He explain a model of atom and said that electrons revolve around a hard core in the center called nucleus.
In 1913 Niels Bohr explains the atomic spectra and put forward the concept of shells and sub-shells.
So overall Structure of an Atom is
- consist of Neutrons in nucleus
- +ve charged protons in nucleus
- A -vely charged electrons revolving around the nucleus
- the electron revolve in shells i.e. K, L, M, and N
- Each shell divide in sub-Shell such as s, p,d and f.
Atom has a specific atomic mass and atomic number
Atomic number = number of protons or electron
Atomic mass = number of protons + number of neutrons in nucleus.
An electron beam makes the object become larger.
answer
Avogadro's law states that, at constant temperature and pressure, the volume of a gas is directly proportional to the number of moles present. In other words, equal volumes of gases at the same pressure and temperature contain the same number of molecules - this is true regardless of their physical properties or chemical nature.
This number of molecules is
6.022
⋅
10
23
and is known as Avogadro's number,
N
A
.
Matematically, Avogadro's law can be written like this
V
n
=
c
o
n
s
t
, or, better yet,
V
1
n
1
=
V
2
n
2
.
Avogadro's law, as well as Boyle's law and Charles' law, are special cases of the ideal gas law,
P
V
=
n
R
T
. If temperature and pressure are kept constant, and knowing that
R
is of course constant, then
P
V
=
n
R
T
→
P
V
n
=
R
T
→
V
n
=
R
T
P
=
c
o
n
s
t
, which represents Avogadro's law.
The ideal gas law can also be written to incorporate
N
A
, since the number of moles are actually the number of molecules divided by Avogadro's number
P
V
=
N
N
A
⋅
R
T
, where
N
represents the number of molecules.