a mixture that can be separated by magnetic attraction
One example of a mixture that can be separated by magnetic attraction is a mixture of iron filings and sand. Iron is a magnetic substance, while sand is not. To separate the mixture, a magnet can be passed over it. The iron filings will be attracted to the magnet and can be pulled away from the sand.
if you dissolve sugar into water until you can no longer see it is the sugar still there or has a new substance been created
When you dissolve sugar into water, the sugar molecules separate and disperse throughout the water. At a microscopic level, the sugar molecules are still present in the solution, but they are no longer visible to the naked eye. The sugar has not transformed into a new substance; it has only dispersed and mixed with the water molecules. If you were to evaporate the water, the sugar molecules would come together again and reappear.
why is water known as a universal solvent
Water is known as a universal solvent because it has the ability to dissolve a wide variety of substances. This is due to its unique molecular structure. Water molecules are polar, meaning they have a slightly positive charge on one end and a slightly negative charge on the other. This polarity allows water molecules to attract and surround other charged or polar molecules, effectively dissolving them.
Many compounds and substances, such as salts, sugars, and certain gases, have polar or ionic bonds, making them water-soluble. However, water can also dissolve nonpolar substances to some extent, like certain oils and fats.
Because of its ability to dissolve a wide range of substances, water plays a crucial role in many biological and chemical processes, making it essential for life as we know it.
what does it mean that water is a polar compound
When we refer to water as a polar compound, it means that the distribution of electrons within the water molecule is uneven. Water molecules consist of two hydrogen atoms bonded to one oxygen atom, forming an "M" shape. The oxygen atom attracts electrons more strongly than the hydrogen atoms, resulting in a partial negative charge (δ-) on the oxygen atom and partial positive charges (δ+) on the hydrogen atoms.
This unequal sharing of electrons creates a polar covalent bond, with the oxygen atom being partially negative and the hydrogen atoms being partially positive. This polarity gives water its unique properties, such as its ability to dissolve other polar or charged substances, its high surface tension, and its capability for hydrogen bonding.