Answer:
Atom consist of three particles proton , electron and neutron.
electrical charge on electron= -1.6022 × 10∧-19 C
electrical charge on proton= +1.6022 × 10∧-19 C
electrical charge on neutron= 0
Explanation:
Atoms are the fundamental unit of matter. Every thing in the universe that occupy space and have mass is called matter. we can say that every matter is composed of atoms. while the atom is composed of subatomic particles called electron proton and neutron.
Electron:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol = e-
Mass= 9.10938356×10-31 Kg
electrical charge on electron= -1.6022 × 10∧-19 C
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Proton and Neutron:
An atom consist of positively charged central core (nucleus) that is made up of Proton and neutron. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P+
electrical charge on proton= +1.6022 × 10∧-19 C
Mass of proton=1.672623×10-27 Kg
Symbol of neutron= n0
Mass of neutron=1.674929×10-27 Kg
electrical charge on neutron= 0
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons.
An ice cube when you heat it it can to water and water is liquid of course
The molar mass of Calcium hydroxide is 74 g/mol
To find the percent composition we have to find the number of atoms of each element in the formula .
So there’s
Calcium - 1
Oxygen - 2
Hydrogen - 2
Then have to multiply the relative atomic mass of each element by the number of atoms
Ca - 40 g/mol x 1 = 40
O - 16 g/mol x 2 = 32
H - 1 g/mol x 2 = 2
Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide
Ca - 40 / 74 x 100 % = 54.0%
O - 32 / 74 x 100 % = 43.2 %
H - 2 / 74 x 100 % = 2.7%
From the options given correct answer is 3rd option
54.0% Ca , 43.0% O and 2.7 % H