The biggest concern is a person using chemistry for negative means. Basically, the amount of energy is constituent atoms, which can help build things, help destroy things faster. I will outline 3 principal concerns below:
The first one is the obvious one – Nuclear Power. There are two basic nuclear reactions: Fission and Fusion, involving breaking up or fusing of atomic nuclei. When nuclei fuse or break apart, they turn into other elements, giving out Energy. This can be related to Einstein’s famous equation where the “Mass” from the nuclei is converted into pure “Energy.” This principle can be used to power a generator to produce, in a sense, a LOT of electricity. But a fateful day in Japan, 1945 reminds us the vicious power of Nuclear Fission, where the Atomic Bomb, caused devastation, and still affects the area today. Also, incidents at Chernobyl and more recently, the Fukushima nuclear meltdown tell us that if not controlled, the vicious energy can destroy the entire planet.
My own take on the Nuclear theme is – Right now, we are at the brink of mastering Fusion Power – although complete mastery is still decades away. After Nuclear Fission is mastered, we may ‘export’ the Sun to Earth and start a Nuclear Fusion reactor. Nuclear Fusion is far better than Fission, and also does not produce waste by-products. So, until we master Nuclear Fusion, this is an intermediate step.
The second one is – Biological Terror Attacks. Although the name tells us its got something to do with Biology and Diseases, but advances in chemistry can mean terrorists deliberately spreading toxins, harmful gases, viruses and likewise among the masses. The 2001 US Anthrax attacks, where letters were laced with infectious material, are a prime example.
... from atoms in one of two ways: nuclear fusion or nuclear fission. In nuclear fusion, energy is released when atoms are combined or ... the sun produces energy. In nuclear fission, energy is released when atoms are split apart. Nuclear power plants use nuclear fission to produce electricity. ... an atom, there is a nucleus. The plural of nucleus is nuclei. Around the nucleus is a cloud of moving ...
The third is the hot issue – found everywhere in science – Global Warming. The CFCs, Carbon Monoxide, Carbon Dioxide were all, in the respective eras, were found as solutions to certain problems. The Greenhouse Effect, a beneficial natural cycle, due to over’grazing’ of industries and careless waste disposal techniques, is turning the planet into a death chamber. The Ozone ‘Hole’ above Antarctica is the cause of ice melting in polar regions, and due to the gaping hole, harmful radiations from the Sun are permeating Earth’s atmosphere. One day, our planet may look like distant Mars. The solution for this, however, may lie, ironically, in Chemistry. Better techniques to flush out the CO2 may be developed, and the new field of ‘Bioplastics’ may yield a biodegradable plastic.
All in All, the Pros of Chemistry far outweigh the cons. The only thing that researchers have to care of is, misusing chemical power.