194: SCIENCE OF COMMON THINGS. 



Vaporization. Why heat converts water into eteam. 



IS 81 Why will alcohol and ether dissolve oil f 



Because the attraction or affinity between the alco- 

 hol or ether and the oil is sufficient to enable them to 

 effect a solution. 



1S8S What effect has heat upon the dissolving power of liquids! 



In most cases the addition of heat to a liquid greatly 

 increases its solvent properties. Hot water will dissolve 

 much more sugar than cold water, and hot water will 

 also dissolve many things which cold water is unable 

 to affect. 



1583 Why does not wood melt like metal ? 



Because the heat of the fire decomposes the wood into 

 gas, smoke, and ashes, and the different parts separate 

 from each other. 



1584 What is meant by vaporization? 



The conversion of a solid or liquid into vapor / as 

 snow or water is converted into vapor by the heat of 

 the sun. 



IS 85 Why is water converted into steam by the heat of the fire f 



Because, when the heat of the fire enters the water, 

 it separates its substance into very minute particles, 

 which (being lighter than air) fly off from the surface 

 in the form of steam. 



1S86 Why do doors swell in rainy weather ? 



Because the air is filled with vapor, w r hich (pene- 

 trating into the pores of the wood) forces its particles 

 farther apart, and swells the door. 



1SS7 Why do doors shrink in dry weather? 



Because the moisture is absorbed from the wood, and, 

 as the particles are brought closer together, the size of 

 the door is lessened / in other words, the wood shrinks. 



1SSS Why does a drop of water sometimes roll along a piece of hot 

 iron without leaving the least trace f 



Because the bottom of the drop is changed into vapor, 

 which buoys the drop up, without allowing it to touch 

 the iron. 



1SS9 Whydoesitrott? 



