Month: December 2016

Burettes

Burettes

Burettes

10/09/16

“How can we  save headaches with precise pouring in chemistry labs?”

 

Doing labwork in chemistry can be very taxing on one’s patience. For example, we might have to pour a solution up with a high decimal value of precision, and even a slight spill can lead to disaster in an experiment! But how can we simplify this? Well, let’s use our engineering mindset to solve this scientific problem. What if we were to create a hyper-accurate glass tube that had a cork on the bottom, which when pulled, would release all of the solution? Wouldn’t this allow for a complete transfer of the liquid that we are working with?  This is the operating principle behind a Burette. Burettes are used widely in chemistry labs for their dual accuracy in measurement and safety.

Topsoil

Topsoil

Topsoil

12/12/16

“What does the upper layer of soil do?”

 

Even though humanity is becoming more urbanized every year, soil is still one of the strongest underpinnings of human civilization. However, what exactly about soil causes it to be so important? Well, it all has to do with the uppermost layer, known as the topsoil. The topsoil  is the top 5-20 centimeters of the Earth’s soil contains all of the essential nutrients for vegetation. Topsoil is filled with life microbial life which can break down dead organic matter present on the surface.

Organic chemistry functional groups

Organic chemistry functional groups

Organic chemistry functional groups

12/11/16

“What causes Organic molecules to have special properties?”

 

Organic compounds are some of the most peculiar forms of nature, making up much of the natural world that we observe. But what makes organic chemicals even more important is that they can be divided into components called functional groups. Functional groups are portions of organic molecules that can be classified into different parts. For example, the thiol chain can be thought of as one such functional group. The composition of functional groups within an organic molecule can change the properties of said molecule, such as the boiling point or smell. There are over 20 functional groups currently identified by Chemists (and for all we know there could be more to come!)

Thiol

Thiol

Thiol

12/10/16

“Why do skunk odors smell so bad?”

 

Have you ever had the misfortune to smell skunk odor? It’s a really bad experience, one that I can thankfully say that I never had. But with a little bit of science, we can all understand why skunk can produce such bad smells.  When a skunk releases its odors, the resulting gas will contain an organic chemical with a most peculiar part known as thiol. Thiol is an organic functional group with an -SH for one of its branches. The sulfur component of thiol is what causes its bad smell. But thiols are not limited exclusively to skunk scents,but can be found in recently chopped onions and even jet fuel!

Quasars

Quasars

Quasars

12/09/16

“What are the things that cause intense streams of energy from far away?”

 

Something interesting seems to be happening. During the dawn of radio astronomy, Scientists noticed very intense signals of electromagnetic radiation. To their surprise, after observing the signals with more traditional telescopes, they found that there were no other forms of visible light surrounding the region. These scientists had termed these objects “quasi-stellar radio sources” or “quasars” for short. After many decades of hard research, Astronomers now hypothesize the light from quasars is the results of matter being ejected by black holes near the speed of light, resulting in energy outputs equivalent to trillions of suns! This high energy is what allows for these quasars to bee seen from so far away, often outshining surrounding it’s surrounding galaxy. Since the light from quasars has to travel a voluminous distance, it could be billions of years by the time we observe it, allowing us to study images of the ancient universe more in depth.

Internal energy

Internal energy

Internal energy

12/08/16

“How can we quantify the energy of internal molecules in a system?”

 

There seems to be a problem. Scientists and engineers often need to analyze the energies associated with objects. However, the atoms of all material are not contiguous with one another but are moving in many directions, each with their own potential and kinetic energy. So how can we quantify such system? Thankfully, after many decades of long research, a most useful concept known as internal energy has been developed. The internal energy of a system is defined by the summation all of the energies arising from the microscopic components of a system, which is often summarized symbolically by the equation U_internal = U_potential+U_kinetic, with U standing for energy

Engineering tolerancing

Engineering tolerancing

Engineering tolerancing

12/07/16

“How do engineers specify the accuracy of their measurements?”

 

One of the most unfortunate aspects of the real world is that there will always be inefficiency, weather it be with the amount of energy available in a system or the weight distribution. One of the inefficiencies include the physical dimensions of an object. Specifically, material parts have small fluctuations in their sizes as a result of the manufacturing process so parts that should measure 5.1 meters in length can come out to be 5.143 or 5.102 meters. For a mass-produced machine, this could be an opprobrium, as the differences in physical size could lead to malfunctioning, which would causally prove disastrous. Luckily, engineers tend to be a very clever people, and they have invented something called engineering tolerancing to solve this issue. When giving off designs to a machinist, engineers will use significant figures to specify the tolerance that part can have. To illustrate a machine such as a cheap toy would not require a high precision, while something like a jet engine will!

Greenhouse gases

Greenhouse gases

Greenhouse gases

12/06/16

“What causes global warming in our atmosphere?”

 

On the news and social media, you will probably hear much discussion relating to a planet destroying phenomena called “global warming” which raises the temperatures of the Earth’s atmosphere. However, what exactly causes this malignant circumstance? As scientific thinkers, let’s get to the bottom of this. To start with, it would be rational to understand what keeps heat on our planet in the first place. In our atmosphere, there are components known as greenhouse gases (namely carbon dioxide, methane, and others) which are capable of absorbing infrared radiation, thereby trapping the warmth emitted by our sun on to our terrestrial home. Before the beginning of the industrial revolution, the levels of greenhouse gases present were just enough to keep the Earth in a temperature equilibrium. However, the many fuel sources used by humanity such as coal, petroleum, and natural gas emit greenhouse gases themselves, therefore adding to this stockpile, and causally a higher amount of heat will be trapped. This rising buildup is most worrying to the future of humanity, with the amount of  CO2 in the atmosphere being over double pre-industrial levels and the average temperature rising over 2 degrees celsius! However, with the use of non-greenhouse gas emitting technology such as solar power and wind turbines, humanity can finally get of this trepidation-filled trend.

Hess’s law

Hess’s law

Hess’s law

12/05/16

“How can we find the change in enthalpy for a chemical reaction without actually performing the reaction?”

Finding the change in enthalpy for a chemical reaction is a rather straightforward procedure, one simply carries forward with the necessary steps and measures the temperature before and after the reaction took place. However, some reactions take an extraordinary long time to perform, or their process is highly volatile. So how can we find the change in enthalpy for such reactions? Well let’s think about it. We know that if we were to take one chemical reaction and reverse it, then the resulting change in enthalpy would reverse in sign. And we know that if we add one element of a chemical equation to the opposite side of an equation containing that element, then they would cancel out. So what if were to take the results of some reactions that we already know, modify them if necessary, and then add them together to fashion the equation of the reaction that we desire? This is the operating principle behind Hess’ law.

To illustrate, let’s examine the reaction Mg(s) + H2O(l) → MgO(s) +H2(g). Since Mg does not react with water, completing this experimentally would be a nightmarish process. However, we can easily obtain the results for Mg(s) +2HCL(aq) → MgCl2(aq) + H2 and MgO(s) + 2HCl(aq) → MgCl2(aq) + H2O. If we were to take the former equation and subtract the latter from it, we would be able to obtain our desired equation. All we need to do is obtain the change in enthalpies for these reactions, and then proceed forward with the mathematics, and next thing you know we would obtain our necessary results!