welcome to Mumu Math and Science in this video let's take a look at the three states of matter we encounter most often here on Earth and then take a look at plasma a fourth state which makes up the majority of the universe matter normally exists as either a solid a liquid or a gas we call this property of matter the phases of matter the three normal phases of matter have unique characteristic a solid holds its shape and has a fixed volume a liquid takes the shape of the container and has a fixed volume a gas takes the shape of the container but has the volume of the container matter can also change from one phase to another when heat or pressure are applied when matter moves from one phase to another this is considered a physical change this triangle summarizes how matter can move from one phase to another another the plus and minus signs indicate if heat is added or subtracted let's first go over the changes that require heat melting is when you move from a solid to a liquid this ice is a solid but as heat is applied it is slowly becoming a liquid evaporation is when you move from a liquid to a gas as this water is heated it is being converted to a gas sublimation is when a solid goes directly to a gas and skips the liquid phase underneath this smoke is a solid bar of dry ice these next changes result when heat is removed freezing is when you go from a liquid to a solid this snow at one time was a liquid but as as it cooled and became cold it became a solid condensation is when you go from a gas to a liquid when water vapor in the air hits a cold glass it will slowly become a liquid and finally deposition is when you go from a gas to a solid for example this person is scraping ice on his windshield the water vapor in the air went from a gas in the air to a solid on the glass now heat some gases even more like really hot and the electrons may become stripped from the nucleus and you create an ionized gas with free negatively charged electrons and positive ions you now have this fourth state of matter called plasma this ionized gas called called plasma has a neutral charge due to the fact there is an equal amount of positively and negatively charged particles plasma is different than almost all gases and can conduct electricity due to the free electrons present some naturally occurring plasma is lightning and the Northern Lights now plasma may may be rare here on Earth but in the universe the Stars including our sun are huge balls of plasma and 99% of the visible part of the universe is plasma thanks for watching and remember kindness multiplies kindness be kind to someone today