Surface Chemistry Class 12

Surface chemistry

name of the chapter: Surface chemistry
Content Provider: FIITJEE
Lecturer from FIITJEE

Introduction based on NCERT :

Surface chemistry deals with phenomena that occur at the surfaces or interfaces. The interface or surface is represented by separating the bulk phases by a hyphen or a slash. For example, the interface between a solid and gas may be represented by solid-gas or solid/gas. Due to complete miscibility, there is no interface between the gases. The bulk phases that we come across in surface chemistry may be pure compounds or solutions. The interface is normally a few molecules thick but its area depends on the size of the particles of bulk phases. Many important phenomena, noticeable amongst these being corrosions, electrode processes, heterogeneous catalysis, dissolution, and crystallization occur at interfaces. The subject of surface chemistry finds many applications in industry, analytical work, and daily life situations. To accomplish surface studies meticulously, it becomes imperative to have a really clean surface. Under very high vacuum of the order of 10–8 to 10–9 pascal, it is now possible to obtain ultra-clean surface of the metals. Solid materials with such clean surfaces need to be stored in a vacuum otherwise these will be covered by molecules of the major components of air namely dioxygen and dinitrogen. In this Unit, you will be studying some important features of surface chemistry such as adsorption, catalysis and colloids including emulsions and gels.

Fiitjee content sharing:

preview only available, not able to download
downloaded copy please ask your faculty

Comments

Periodic Table Shortcut

Periodic table shortcut Name of the page: shortcut for periodic table Done by: FIITJEE Student Applicable for all the classes What is a Periodic Table? a table of the chemical elements arranged in order of atomic number, usually in rows, so that elements with similar atomic structure (and hence similar chemical properties) appear in vertical columns. The periodic table, also known as the periodic table of elements, is a tabular display of the chemical elements, which are arranged by atomic number, electron configuration, and recurring chemical properties. The structure of the table shows periodic trends. who invented the periodic table? many collections of scientists invented it. Embedded PDF:

powerpoint metals and non metals

PowerPoint presentation of metals and nonmetals name of the chapter: Metals and nonmetals Content Provider: FIITJEE Lecturer from FIITJEE an intro that just known to us (recall): Metals are described as chemical elements that readily lose valence electrons to form positive ions (cations). Examples : Aluminium, copper, iron, tin, gold. Around 90 of the total 118 elements are metals. To know more about Metals, visit Physical Properties Physical Properties of Nonmetals Occur as solids, liquids, and gases at room temperature Brittle Non-malleable Non-ductile Non-sonorous Bad conductors of heat and electricity Exceptions in Physical Properties Alkali metals (Na, K, Li) can be cut using a knife. Mercury is a liquid metal. Lead and mercury are poor conductors of heat. Mercury expands significantly for the slightest change in temperature. Gallium and cesium have a very low melting point Iodine is non-metal but it has luster. Graphite conducts electricity. Diamond conducts heat

Dark Matter And Dark Energy

Dark matter and dark energy Formation of dark energy – When the universe formed after the big bang theory. It started as a small ball of energy, began expanding, and still continues. – However, the thing that puzzles scientists are that instead of the expansion slowing down its rate is increasing, going against normal physics. Formation of dark energy – This explains the occurrence of energy causing the expansion which scientists term as dark energy. – According to scientists 68% of the universe is dark energy, 27% is dark matter and only 5% is what we currently can observe. – The theory to this was first given by Einstein’s long-forgotten gravity theory which consisted of a cosmological constant. Why is there dark energy? – Scientists have now given 3 explanations for dark energy: – The first is of course Einstein's theory of gravity. – a new theory could include some kind of fi

FIITJEE Chemistry

Search This Blog