The water molecule is a very special molecule. It has a small positive charge on one end and a small negative charge on the other end. Because of this it has the ability to dissolve many substances.
We can demonstrate this by using a charged balloon. View the video on the right. See how a charged object attracts the column of water.

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The water molecules are attracted to the individual salt particles forming the crystal. As water molecules approach the crystal they surround each particle and separate it from the rest of the salt crystal. Individual salt particles now surrounded by water molecules float freely in the water. A salt solution is formed.

The salt is said to be soluble in water, in other words, water can move in and surround each particle thus breaking up the crystal into individual particles.

Sugar is also soluble in water and yes water also disrupts the sugar crystals by surrounding each particle of sugar and causing to float freely in the solution.



Salt dissolves quicker in hot water than in cold water. The reason is that in hot water, water molecules have more energy and travel faster than in cold. They have more energy to disrupt the salt crystal.

A liquid that is used to dissolve another substance is given the general term of solvent, while he substance being dissolved is known ans the solute. In this case salt is the solute and wate ris the solvent.

Some substances are insoluble. That is, water molecules cannot dislodge the particles that make up the crystal. The particles of an insoluble substance are held too tightly to the other particles in the crystal.
1) Which word best describes sand in water?
2) Explain how water molecules dissolve salt?
3) What makes water molecules able to dislodge the particles of a soluble substance?
4) Water is made up of
5) In a solution of water and sugar sugar is
Continue with separating mixtures