Neon atom can exist freely in nature but sodium atom can't why

Balance this equation co2(g) + h2o (g) show that the balanced equation obeys the law if conversation of mass

Oil rich countries in the middle east cover about 4% of earths total land area but prossess about 48% of the worlds known oil reserves what is the main reason for high concentration of reserves in this part of the world

Which of the following is a physical change? a.burning a piece of wood b.sawing a piece of wood in half c.rust forming on an iron fence d.a copper roof changing color from orange to green