Alexa, the voice service that powers Echo, provides capabilities, or skills, that enable customers to interact with devices in a more intuitive way using voice. Examples of these skills include the ability to play music, answer general questions, set an alarm or timer and more.
1 Water can dissolve salt because the positive part of water molecules attracts the negative chloride ions and the negative part of water molecules attracts the positive sodium ions. 2  The amount of a substance that can dissolve in a liquid (at a particular temperature) is called the solubility of the substance.
Dissolving salt. 1  When salt crystals are placed in water, the positive ends of the water molecules attract the negative chloride ions. 2  The negative ends of the water molecules attract the positive sodium ions. 3  When attraction between the water and the ions overcomes the attraction the ions have for each other, the salt dissolves.