InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
a twalenă¤pipe-autawaln at thiof a house i 4X10t.CXplain |
| Answer» <p>Detergent is different. The surfactants it contains are made of molecules that have two different ends. One end is strongly attracted to water; the other is attracted to oily substances like grease. ... During the final spin, the dirty water flushes away, leaving your jeans clean again!The cleverest part of a washing machine isn't the drum or the drive belt, the electric motor that spins it around or the electronic circuit that controls the program: it's the detergent (soap powder or liquid) you put in right at the start. Water alone can't clean clothes because it won't attach to molecules of grease and dirt. Detergent is different. The surfactants it contains are made of molecules that have two different ends. One end is strongly attracted to water; the other is attracted to oily substances like grease.</p><p>Suppose you got some grease on your favorite jeans. No problem! Throw them into the washing machine with some detergent and this is what happens:</p><p>During the wash cycle, the surfactant (represented here by the orange blob) mixes with water.The grease-loving ends of the surfactant molecules start to attach themselves to the dirt on your jeans (shown by the brown blob on the leg). The tumbling motion beats your jeans about and breaks the dirt and grease into smaller, easier-to-remove pieces.During the rinse cycle, water molecules (blue blob) moving past attach themselves to the opposite, water-loving ends of the surfactant molecules.The water molecules pull the surfactant and dirt away from the jeans. During the final spin, the dirty water flushes away, leaving your jeans clean again!This is why soap and water clean better than either one of these things alone.</p> | |