meaning of sponge and piston

why methane is in compressible?

What is mass of on object?

What is difference between evaporation nad vapourisation?

burns caused by steams are more severe tan those caused by boiling water

naphthalene balls disappeare when exposed to air

properties of matter

explain the termcrystal lattice

What is mant by Diffusion?

What is meant by Fusion?

what is mean by world of matter?

which are the four characteristics of particles of matter?

Is matter continous or paticulate?

what is the photoelectric effect ?

what is meant by rubidium atoms

what is meant byS.I unit C.G.S

unit. explain me clearly.