Compounds are substances made of at least 2 different elements. Molecules have at least 2 atoms, doesn't have to be different elements. Compounds and molecules both work.
The reaction 
→ 
is best classified as double displacement reaction.
Those reaction in which two compounds react by exchanges of ions to form two new compounds is called double displacement reaction. The easiest way to identify double displacement reactions is to check to see whether the cations exchanged anions with each other or not . Always balanced chemical equation is used to determine.
There are three types of double displacement reaction which is given as,
- Precipitation
- Neutralization
- Gas formation
The real world example of double displacement reaction is combining vinegar and baking soda to create homemade volcano.
learn more about double displacement reaction
brainly.com/question/13870042?
#SPJ4
C( n)H(2n) is the general formula, eg: Cyclohexane is C6H12
Earth contains huge quantities of water in its oceans, lakes, rivers, the atmosphere, and believe it or not, in the rocks of the inner Earth. Over millions of years, much of this water is recycled between the inner Earth, the oceans and rivers, and the atmosphere. This cycling process means that freshwater is constantly made available to Earth's surface where we all live. Our planet is also very efficient at keeping this water. Water, as a vapor in our atmosphere, could potentially escape into space from Earth. But the water doesn't escape because certain regions of the atmosphere are extremely cold. (At an altitude of 15 kilometers, for example, the temperature of the atmosphere is as low as -60° Celsius!) At this frigid temperature, water forms solid crystals that fall back to Earth's surface.
Many people live faraway from freshwater sources. They need to carry their water home.
While our planet as a whole may never run out of water, it's important to remember that clean freshwater is not always available where and when humans need it. In fact, half of the world's freshwater can be found in only six countries. More than a billion people live without enough safe, clean water.
Also, every drop of water that we use continues through the water cycle. Stuff we put down the drain ends up in someone or something else's water. We can help protect the quality of our planet's freshwater by using it more wisely.
