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00:00hi kids today we will learn about various properties of matter so let's
00:08get started luster we can say this monument is lustrous
00:17but why we will call it lustrous because it has a quality of shining or reflecting
00:26light from its surface so luster is a quality of shining by reflecting light
00:34all the objects with shiny surfaces are called lustrous objects luster is a
00:42physical property of metals mainly iron copper aluminum nickels and steel but
00:52nonmetals can also have this quality light diamond graphite are nonmetals but
00:59highly lustrous now let's learn another property that is malleability
01:07malleability is a property that tells whether something can be molded or
01:13deformed without breaking that is how flexible or easily shaped something can
01:21be without breaking more specifically it is the characteristics of metal that
01:29allows it to be beaten or rolled into very thin sheets without cracking or
01:36rupturing malleability is also called plasticity example aluminum is capable
01:46of being extended or shaped by hammering or by pressure from rollers
01:52into very thin sheets without breaking aluminum foil that we all use
01:59demonstrates the ability of aluminum to be compressed into very thin flat
02:05sheets gold silver aluminum copper are some of the highly malleable metals very
02:15beautiful and exquisite designs of jewelries are made with gold and silver
02:21because of this malleable property now let's have a look at another property
02:28which is ductility of metals this property is known as ductile ductility
02:37is a solid materials ability to deform under tensile strength tensile strength
02:44is a maximum stress a metal can withstand before breaking more
02:51specifically ductility is this materials ability to be stretched into a wire
02:58metals like copper iron nickel manganese silver iridium osmium tungsten tantalum
03:08hafnium rhenium tin and zirconium can be drawn into very long wires ductility
03:16is opposite of rittleness where a metal breaks suddenly without any deformation
03:23in its shape when a metal or any matter is put under maximum pressure and it
03:31breaks suddenly without much deformation or change in shape of the matter it's
03:37called brittle fracture and such matter or a metal is not at all ductile but
03:46such metal is called brittle metal now let's learn some differences between
03:54malleability and ductility ductility is the ability of a material to be stretched
04:04into a wire and malleability is a property of material where it can be
04:13stretched into thin sheets both these mechanical properties are aspects of
04:19plasticity that is the extent to which a solid material can be plastically
04:26deformed without fracture for example gold is a highly ductile and malleable
04:34metal that is gold can be stretched into wires also and it can be stretched into
04:41thin sheets too but not all metals may depict ductility and malleability at the
04:50same time for instance lead has low ductility but high malleability now
05:00let's learn another property of matter which is hardness hardness is the
05:07measure of how resistant solid matter is to various kinds of permanent shape
05:13changes some materials such as metal are harder than others the greater the
05:22hardness of the metal the greater is its resistance to any deformation we have a
05:30lot of hard materials which are naturally present in our environment and
05:35some are man-made most often diamond is considered to be the hardest material
05:42ever known but scientists have found two more minerals that are even harder
05:50than diamond word site boron nitride and Lons delight they exist in nature but
05:58can also be made artificially Lons delight is sometimes formed when
06:04meteorites containing graphite hit the earth while word site boron nitride is
06:10formed during volcanic eruptions that produce very high temperatures and
06:15pressures now let's learn another property of matter it is texture texture
06:26is the feel appearance or consistency of a surface or a substance it's the
06:34physical feel of something it can be smooth rough slimy and spiky or even
06:42something in between for example sandpaper is very rough it has a gritty
06:50rough texture so friends today we learned some properties of matter now
07:00you may go ahead and take a quiz to learn more bye-bye