Just like how heat moves from a region of higher
temperature to a region of lower temperature, molecules also tend to move from
a region of higher concentration to a region of lower concentration. This is
called natural diffusion and is naturally happening to reach stability.
Explanation:
In any chemical change, one or more initial substances change into a different substance or substances. ... According to the law of conservation of matter, matter is neither created nor destroyed, so we must have the same number and kind of atoms after the chemical change as were present before the chemical change
Example:
The carbon atom in coal becomes carbon dioxide when it is burned. The carbon atom changes from a solid structure to a gas but its mass does not change.
When it is tilted away from the Sun, it is winter in the northern hemisphere. In between we have autumn and spring. The day that the Earth's North Pole is tilted closest to the sun is called the summer solstice. This is the longest day (most daylight hours) of the year for people living in the northern hemisphere.