What is as big as a castle but lighter then air?

Is splitting wood chemical or physical change? What chemical do you put in water to make it drinkable? How are flame test used in astronomy science? What does palladium look like? Is there any difference between compound microscope and inverted microscope? What gives transport facility to cell? Where was the film red planet filmed? What is the function of a leaf pore guard cell? Why do more males experience serious injuries than females? Some plants attract only one type of pollinator describe an advantage and a diadvantage of having only one type of pollinator? What have people done to solve global warming? What are Inputs transformation process and uses of maize? How many ml in g soup? Which atoms never join groups and are considered monoatomic? What has more bacteria toilet water or water fountain water? Do All biochemical pathways have the same number of enzymatic reactions? What is ssd super solution? Why have geographers created ecozones? What is the volcano called in Iceland? What are some stress resistant traits?