Answer:
The final temperature is 20.3 °C
Explanation:
Considering that:-
Heat gain by water = Heat lost by brass
Thus,
Where, negative sign signifies heat loss
Or,
For water:
Mass = 300.0 g
Initial temperature = 20.0 °C
Specific heat of water = 4.184 J/g°C
For brass:
Mass = 19.0 g
Initial temperature = 81.7 °C
Specific heat of water = 0.375 J/g°C
So,
<u>Hence, the final temperature is 20.3 °C</u>
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
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.
