Answer:
The atom is divisible particle and can be subdivided into smaller particles proton, neutron and electrons was not stated by John dalton.
Explanation:
The postulate of Dalton's atomic theory that atom is indivisible particle and can not be subdivided into smaller particles was later changed because atom can be divided into neutrons, protons and electrons.
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
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Proton and neutron:
While neutron and proton are present inside the nucleus. 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⁺
Symbol of neutron= n⁰
Mass of proton=1.672623×10⁻²⁷ Kg
Mass of neutron=1.674929×10⁻²⁷ Kg
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron.
Answer:
If the moles of gas are tripled, the volume must also triple.
Explanation:
According to Avogadro law,
Equal volume of all the gases at same temperature and pressure have equal number of molecules.
The number of moles and volume are directly related to each other. By increasing the number of moles volume also goes to increase with same ratio.
When number of moles decreases the volume also goes to decrease at constant temperature and pressure.
Mathematical expression:
V ∝ n
V = Kn
V/n = k
When volume is changed from V₁ to V₂ by changing the number of moles from n₁ to n₂. Then expression will be,
V₁/n₁ = V₂/n₂
An anion has a negative charge, while a cation has a positive charge.
Answer: conversion of ice to steam
Explanation: Endothermic process is one in which energy is absorbed by the system.
Conversion of ice to steam is change of solid phase to gaseous phase, thus energy is required to break the strong inter molecular forces of attraction in solids to convert it into gaseous phase.
Conversion of steam to ice, conversion of steam to water and conversion of water to ice releases energy and are examples of exothermic processes.
