Chemistry is an important part of your everyday life.
1. sky is blue - An object is colored because of the light it reflects. The white light of the sun contains all the wavelengths, but when it hits an object some of its wavelengths are absorbed and some are reflected. The color of the sky can be explained taking into account phenomena called Rayleigh scattering which consists of the scattering of light by particles much smaller than their wavelength. This effect is especially strong when light passes through the gases.
2. Ice Float over water - Ice is less dense than liquid water. The heavier water shifts the ice lighter, so the ice floats on top.
3. How Sunscreen Works - Sunscreen combines organic and inorganic chemicals to filter out sunlight so that less of it reaches the deeper layers of your skin. Reflective particles on the sunscreen generally consist of zinc oxide or titanium oxide.
4. Are meals cooked faster in a pressure cooker? - A pressure cooker has a more elaborate lid that seals the pot completely. When we heat the boiling water and the steam can not escape, so it stays inside and begins to accumulate pressure. Under pressure, cooking temperatures increase much more than under normal conditions, so food is cooked much faster.
5. The chemistry of love: chemistry is at the bottom of every step of a relationship. When we fall in love, our brain undergoes some changes and also certain chemical compounds are released. Love is driven by these hormones: oxytocin, vasopressin, endorphins.
6. Coffee keeps us awake - Coffee keeps us awake due to the presence of a chemical called adenosine in your brain. It binds to certain receptors and slows down the activity of nerve cells when sleep is signaled.
7. Vegetables are colored - Many vegetables and fruits are heavily colored because they contain a special type of chemical compound called carotenoids. These compounds have an area called choromophore, which absorbs and detaches particular wavelengths of light, generating the color we then perceive.
8. How do you clean the soap? - The soap is formed by molecules with a "head" that likes water (hydrophilic) and a long chain that hates it (hydrophobic). Then, when soap is added to the water, the long hydrophobic chains of its molecules bind the oil particles, while the hydrophilic heads enter the water. An oil-in-water emulsion is then formed, which means that the oil particles are suspended in the water and released from the fabric. With the rinse, remove the emulsion.
9. We cry while we cut the onions. The onions make you cry because of the presence of sulfur in the cells that break after cutting the onions. This sulfur mixes with moisture and therefore irritates the eyes.