Physical Properties Of Gallium: The Wonder Metal

Physical Properties of Gallium: The Wonder Metal

Gallium does not crystallize in any of the simple crystal structures. The stable phase under normal conditions isorthorhombic with 8 atoms in the conventional unit cell. Within a unit cell, each atom has only one nearest neighbor (at a distance of 244 pm). The remaining six unit cell neighbors are spaced 27, 30 and 39 pm farther away, and they are grouped in pairs with the same distance. Many stable and metastable phases are found as function of temperature and pressure.

The bonding between the two nearest neighbors is covalent, hence Ga2 dimers are seen as the fundamental building blocks of the crystal. This explains the drop of the melting point compared to its neighbor elements aluminium and indium.

The physical properties of gallium are highly anisotropic, i.e. have different values along the three major crystallographical axes a, b, and c (see table); for this reason, there is a significant difference between the linear (α) and volume thermal expansion coefficients. The properties of gallium are also strongly temperature-dependent, especially near the melting point. For example, the thermal expansion coefficient increases by several hundred percent upon melting.

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Hogwarts Houses as Van Gogh Quotes

Hufflepuff: “How wonderful the color yellow is. It stands for the sun.”

Ravenclaw: “I don’t know anything with certainty, but seeing the stars makes me dream.”

Gryffindor: “What would life be if we had no courage to attempt anything?”

Slytherin: “I put my heart and soul into my work, and I have lost my mind in the process.”

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ship-happenss

6 years ago

“Es ist nur EIN Strohhalm”, sagten 8 Milliarden Menschen.

Genauso ist es mit jeder anderen scheinbar unbedeutenden Entscheidung in unserem Alltag.

Actual advice on how to study for engineering courses from a first year student

Okay so I just finished my first semester in university and lets just say I’ve got to change my whole learning/studying style to be able to survive here. Here are some of the things I’ve learnt to do and will be doing in second semester:

1. Start backwards:

Actual Advice On How To Study For Engineering Courses from A First Year Student

I highschool, you try to learn the subject by going to class, listening to the teacher, then going home, reading the textbook, then doing the homework, then making notes, then studying for the final. In engineering, you have to do this backwards: You will realize that you are going to be basically teaching yourself the content one way or another soon before the finals, so better start now. First, go through the past exams and past papers - make a list of all the major topics covered (example: if in an electrical circuits course, a question on a past final exam is “find the equivalent circuit using thevenin’s theorem” then write Thevenin’s theorem as a topic to be learned). Then go on youtube and find videos that explain each of these topics to you and make rough notes on these topics. (Reblog if you want me to make a master list of all the youtubers that teach engineering really well). Then go through he textbook and find sample questions not he theorem/topic you learnt off of youtube, and solve them. Then write your doubts in a notebook. Then go to class and have two notebooks open : one where you are taking notes of what the prof is saying, and one which has your practice problems solved, and see if the prof clarifies your doubts in the lecture. The lecture should be review of what you learnt at home!!!! Then, after class go to the prof and clarify any doubts. Then go home and make final notes on the topic. I like to make notes on cue cards (more on this later). Then go back to the final exam and see if you can solve the problem.

2. Make cue cards:

I like to get index cards and write a short note on how to solve each type of question I am likely to see on a final exam on each question card. Example: one cue card for “how to find resistance using wheatstone bridge” . I link the cue cards with a clip and its easier to carry the around and study.

3. Get pretty notebooks and organize your stationary. Its easier to stay focused when everything is pretty.