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.
18 is the max number of electrons in 1 orbital
Answer:
The mass of gold in crown is 960.61 g.And the volume of gold is
.
Explanation:
Density is defined as mass of the substance present in unit volume of the substance.
Mass of gold in an alloy of crown= m
Mass of silver in an alloy of crown = M
Volume gold in an alloy of crown= v
Volume of silver in an alloy of crown = V
Density of gold = 
Density of silver = 
Volume of the crown = 

..(1)
Mass of eh crown = 1050 g
..(2)
Solving equation (1) and (2):
m = 960.61 g
M = 89.39 g
Volume of the gold = v = 
Volume of silver = V = 
The mass of gold in crown is 960.61 g.And the volume of gold is
.
It would be 1.55x10 to the 9th
hope that helps you
The buoyancy of an object is dictated by its density. So let us calculate for density, where:density = mass / volume
Calculate the volume first of a solid cube:volume = (6 cm)^3 = 216 cm^3 = 216 mL
Therefore density is:density = 270 g / 216 mLdensity = 1.25 g / mL
Therefore this object will float in the layer in which the density is more than 1.25 g / mL.