Importance of chemistry in our daily life
Chemistry is everything around you. You find chemistry in daily life in the foods you eat, the air you breathe, cleaning chemicals, your emotions and literally every object you can see or touch. While some may be obvious, some other might surprise you. Let’s find out the Chemistry in our everyday life:
1. Your body-
Oxygen (O) – 65% – Oxygen together with hydrogen form water, which is the primary solvent found in the body and is used to regulate temperature and osmotic pressure. Oxygen is found in many key organic compounds.
2. Carbon (C) – 18% – Carbon has four bonding sites for other atoms, which makes it the key atom for organic chemistry. Carbon chains are used to build carbohydrates, fats, nucleic acids, and proteins. Breaking bonds with carbon is an energy source.
3. Hydrogen (H) – 10% – Hydrogen is found in water and in all organic molecules.
4. Nitrogen (N) – 3% – Nitrogen is found in proteins and in the nucleic acids that make up the genetic code.
5. Calcium (Ca) – 1.5% – Calcium is the most abundant mineral in the body. It’s used as a structural material in bones, but it is essential for protein regulation and muscle contraction.
6. Phosphorus (P) – 1.0% – Phosphorus is found in the molecule ATP, which is the primary energy carrier in cells. It’s also found in bone.
7. Potassium (K) – 0.35% – Potassium is an important electrolyte. It’s used to transmit nerve impulses and heartbeat regulation.
1. Sulfur (S) – 0.25% – Two amino acids include sulfur. The bonds sulfur forms help give proteins the shape they need to perform their functions.
2. Sodium (Na) – 0.15% – Sodium is an important electrolyte. Like potassium, it is used for nerve signaling. Sodium is one of the electrolytes that helps regulate the amount of water in the body.
3. Chlorine (Cl) – 0.15% – Chlorine is an important negatively-charged ion (anion) used to maintain fluid balance.
4. Magnesium (Mg) – 0.05% – Magnesium is involved in over 300 metabolic reactions. It’s used to build the structure of muscles and bones and is an important cofactor in enzymatic reactions.
5. Iron (Fe) – 0.006% – Iron is found in hemoglobin, the molecule responsible for oxygen transport in red blood cells.
6. Copper (Cu), Zinc (Zn), Selenium (Se), Molybdenum (Mo), Fluorine (F), Iodine (I), Manganese (Mn), Cobalt (Co) – total less than 0.70%
7. Lithium (Li), Strontium (Sr), Aluminum (Al), Silicon (Si), Lead (Pb), Vanadium (V), Arsenic (As), Bromine (Br) – present in trace amounts
• Your emotions- The emotions that you feel are a result of chemical messengers, primarily neurotransmitters. Love, jealousy, envy, infatuation and infidelity all share a basis in chemistry. The sweaty palms and pounding heart of infatuation are caused by higher than normal levels of norepinepherine. Meanwhile, the ‘high’ of being in love is due to a rush of phenylethylamine and dopamine.
• Soaps and detergents- Everyday while washing our clothes we use soaps and detergents. These soaps and detergents are made of chemical ingredients. Soaps are sodium or potassium fatty acids salts, produced from the hydrolysis of fats in a chemical reaction called saponification. Each soap molecule has a long hydrocarbon chain, sometimes called its ‘tail’, with a carboxylate ‘head’. In water, the sodium or potassium ions float free, leaving a negatively-charged head. Soap is an excellent cleanser because of its ability to act as an emulsifying agent.An emulsifier is capable of dispersing one liquid into another immiscible liquid. This means that while oil (which attracts dirt) doesn’t naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.
• Onions- Onions are rich in two health-benefiting compounds: flavonoids and sulfur-containing compounds
• For a long time, it was thought that lachrymatory factor was produced by alliinase, a critical enzyme in a pathway of onion flavor synthesis. (An enzyme is a protein that helps speed up a reaction, in this case a conversion of one compound into another.) However, in 2002, a previously unknown enzyme – not alliinase – was shown to be responsible for synthesizing lachrymatory factor. This new enzyme was termed lachrymatory-factor synthase, a very straightforward name. The discovery was significant because inhibiting alliinase would lead to reduction of both lachrymatory factor and other flavor compounds, whereas inhibition of lachrymatory-factor synthase would only prevent the synthesis of lachrymatory factor, thus making you no longer tearful, while keeping the flavor intact.
• Let’s look at the chemistry of onion flavor synthesis more closely. When an onion is damaged through cutting or crushing, a volatile sulfur compound is released into the air. This compound is broken down into an unstable intermediate with the help of alliinase. This product can then either turn into lachrymatory factor with the help of lachrymatory-factor synthase or spontaneously turn into thiosulfinate. This thiosulfinate is not only responsible for the onion’s distinct odor and flavor, but also gets converted into other sulfur-containing compounds with potential health benefits, namely anti-inflammation, anti-blood clotting, anti-cancer, anti-asthma, and lowering cholesterol levels. Now you see why inhibiting alliinase all together is a bad idea?
• As a matter of fact, inhibiting lachrymatory-factor synthase would not only stop onions from making your eyes water, but would also increase the yield of thiosulfinate because all the sulfur compounds released from onions will be converted into thiosulfinate. So the onions lacking lachrymatory-factor synthase activity would be tear-free but retain that odor and flavor distinct to fresh onions.
Ice floats on water- Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a liter of ice weighs less than a liter water. The heavier water displaces the lighter ice, so ice floats to the top. One consequence of this is that lakes and rivers freeze from top to bottom, allowing fish to survive even when the surface of a lake has frozen over. If ice sank, the water would be displaced to the top and exposed to the colder temperature, forcing rivers and lakes to fill with ice and freeze solid.
Sunscreen- what you need to know is that in the sunscreen world, two labels are used to describe it: “mineral” and “chemical” sunscreen. “Mineral” sunscreens typically refer to zinc oxide and titanium dioxide, which are chemical compounds labeled “inorganic” because they do not contain carbon atoms in their overall structure. Conversely, “chemical” sunscreens are made up of carbon-containing molecules that absorb light, and because they contain carbon, chemists refer to them as “organic.”
Below is the chemical structure for oxybenzone. When an organic molecule has a lot of double bonds like you see below, it’s good at absorbing UV light, the same light that we are trying to block using sunscreen (absorbing in this case means the same as blocking). This is what makes oxybenzone a good sunscreen.
(Drawn using Chemdoodle, http://web.chemdoodle.com)
The green sunscreen shown above is the one given to us by the children’s museum, and it contains zinc oxide (ZnO), and titanium dioxide (TiO2). These are also chemicals, just a different type of chemical. ZnO and TiO2 are not carbon-containing molecules (“organic”), but rather inorganic UV blockers. Many sunscreen brands refer to zinc oxide and titanium dioxide as “mineral” sunscreens. This term evokes thoughts of gathering rocks and grinding them up and plastering the mix on your body. But this actually is a bit of marketing language. Zinc oxide and titanium dioxide are also chemicals.
H. A., V. W. Rodwell, P. A. Mayes, Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.
Onions—A global benefit to health
Burnett, M. E. and Wang, S. Q. (2011), Current sunscreen controversies: a critical review. Photodermatology, Photoimmunology & Photomedicine, 27: 58–67.
2 Schauder, S., Ippen, H. (1997) Contact and photocontact sensitivity to sunscreens. Review of a 15 year experience and of the literature. Contact Dermatitis, 37, 221–232 3 Janjua, N. R., Mogensen, B., Andersson, A., Jørgen, H. P., Henriksen, M., Skakkebæk, N.,E., & Wulf, H. C. (2004). Systemic absorption of the sunscreens benzophenone-3, octyl-methoxycinnamate, and 3-(4-methyl-benzylidene) camphor after whole-body topical application and reproductive hormone levels in humans. The Journal of Investigative Dermatology, 123(1), 57-61.