Chemistry why questions

Do you know how detergents work? Do you know better than to mix bleach and ammonia or bleach and vinegar? What other everyday chemicals pose a hazard when combined? Chlorophyll is the pigment in plants that makes them appear green, but it isn't the only pigment that is present.

Do you know what affects the apparent color of leaves? First, you should know the answer is 'yes' and then be able to explain why it's completely impractical. Does it do any good? How does it work? Are all salts equally effective? Do you know how bleach works? No, you don't need to be able to list every single one. You ought to be able to name the top three without thinking. It's good to know the top six.

Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content. Create a personalised content profile. Note: I had forgotten about a wonderful piece by Philip Ball in the pages of this magazine which expounded on some other fundamental questions of concern to chemists. I thank SeeArrOh for the reminder. The views expressed are those of the author s and are not necessarily those of Scientific American. Ashutosh Jogalekar is a chemist interested in the history, philosophy and sociology of science.

He is fascinated by the logic of scientific discovery and by the interaction of science with public sentiments and policy. He blogs at The Curious Wavefunction and can be reached at curiouswavefunction gmail.

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Go Paperless with Digital. Can we ever beat photosynthesis? How do we make chemistry environmentally friendly? Can we design the perfect drug? How do we sell chemistry to the public? Follow Ashutosh Jogalekar on Twitter Recent Articles by Ashutosh Jogalekar Richard Feynman, sexism and changing perceptions of a scientific icon Gavrilo Princip, conspiracy theories and the fragility of cause and effect New Vertex drug combination for cystic fibrosis represents a triumph of drug discovery research.

Get smart. Sign up for our email newsletter. Sign Up. Read More Previous. Support science journalism. Knowledge awaits. See Subscription Options Already a subscriber? Create Account See Subscription Options. There are two more metals in this group: Caesium and Francium. These both explode on contact with water. Fast Fact: The group I metals are called 'alkali metals'; when they react with water they form an alkali solution.

Glow Sticks are particularly useful when light is needed but sparks could be deadly. The glow in a glow stick is the result of two chemicals reacting together and giving off light energy in a process called chemiluminscence. Inside a glow stick is a glass vial containing different chemicals usually phenyl oxalate and a fluorescent dye.

This sits inside other chemicals usually hydrogen peroxide contained by the plastic tube. When you snap the stick, the glass vial breaks and the two chemicals mix and react. This is a process known as chemiluminescence: when the chemicals mix, electrons in the constituent atoms are raised to a higher energy level.

When these electrons return to their normal state, they release light energy. Glow sticks have a wide variety of applications from military, to diving, to night-time fishing lures. Fireworks are a personal favourite of mine, with firework science being particularly popular amongst my pupils. The different colours are created using different chemicals, and one of two different chemical reactions: incandescence light created through heat and luminescence light without heat.

Fast Fact: The largest single firework to be set off was in Japan in The burst was over 1 kilometre across. Oranges, reds and whites are usually made through incandescence. Blues and greens are usually made through luminescence. Alloys are mixtures containing at least one metal. We use metals for many jobs in our technological world and sometimes a metallic element just won't cut it. Take iron - whilst extremely strong, it is also very brittle Add in a little carbon and you make steel - an alloy with the strength of iron but it not brittle.

Alloys contain atoms of different sizes, which makes it more difficult for the atoms to slide over one another. This makes alloys harder than the pure metal. Certain mixtures are even more impressive. Mix nickel and titanium and you get Nitinol, a smart alloy used to make spectacle frames. If you bend your glasses let's say, by sitting on them Match heads are made using phosphorus - a highly combustible element - that catches fire due to the friction caused when striking the match.

Safety matches are slightly different. They will only light if you strike them using the surface on the side of the box. In this case, the match head contains potassium chlorate - an accelerant that speeds up the reaction. The rough side of the box contains most of the phosphorus. Bring the two together and add the heat generated by friction, and you have a flame. Waterproof matches have a thin coating of wax over the whole match.

This is removed when striking the head against the box, exposing the phosphorus. This allows the match to catch. To give you enough time to move the match to whatever you wish to light, most matchsticks are treated with paraffin candle wax.

The earliest match is thought to have arisen in China in AD. These were nothing more than sticks impregnated with sulphur. Bubbles in fizzy drinks can only form at points called nucleation sites - these are sharp edges or bits of dirt or grime that helps the release of carbon dioxide gas.

A mento is actually not as smooth as it appears. Under a microscope you can see that there are millions of tiny craters on the surface. Each of these provides a nucleation site for carbon dioxide gas to form. Read more here. Fast Fact: Diet coke works best because the surface tension in the drink is much lower than regular coke - this allows bubbles to form more easily.

This is due to the substitution of sugar with the sweetener aspartame. The ozone layer is a massive shield that surrounds the Earth, 50kms above the surface of the planet.