Show i I I WHY I IA WHY DOES HOT WATER CRACK A COLD GLASS Hot water will not always cause a I cold glass to crack but it Is very apt to especially a thick glass The very thin glasses will not crack The test tubes used by chemists are made of very thin glass and will not crack when hot liquids are poured into themI them When a glass cracks after you have poured a hot liquid into it It does I so because as soon as the hot liquid is poured In the particles of or glass which form the Inside of the glass become heated and expand They begin begin begin be be- gin to do this before the particles which form the tho outside of the glass lass become becom be be- com come heated and In their efforts to expand the Inside particles of glass literally break away from the particles parti cles Iles which form the outside causing the crack The same thing happens if you put very cold water into a hot hotI glass excepting in this instance the inside particles of the glass contract I before the particles which form the outside of oC the glass have had time to become cool and do likewise |