So our atoms of neon consist of a nucleus with a plus charge surrounded by 10 electrons in an electron cloud. Ionic bonds are electrostatic attractions between positively and negatively charged ions.
Atoms can lose or gain electrons to form positive or negative ions. We need to look at the five statements and find the one that accounts for the fact that atoms of neon do not form ionic bonds. The first thing it will be helpful to remember is that neon is one of the noble gases, which are well-known for not forming any bonds at all, with some exceptions.
However, generally speaking, neon goes around as single atoms. Statement A suggests that atoms of neon have delocalized electrons. When considering bonding, we generally think about metallic bonding when we consider delocalized electrons.
The next statement says that atoms of neon must gain or lose four electrons to form a stable octet in their outer shell. The outer shell is sometimes also known as the valence shell. The word octet in this statement should hint towards the octet rule, which tells us that atoms tend to react to acquire eight electrons in their outer shell. Do you think it will lose seven electrons or gain one electron to obtain an octet in its outermost electron shell? The octet rule is the concept that atoms tend to have eight electrons in their valence electron shell.
Ionic bonds are formed by the attraction between oppositely charged ions. Positive charges repel each other, so an ionic compound is not likely between two positively charged ions. Selenium is more likely to gain two electrons. Iodine is more likely to gain one electron. Learning Objectives Define the octet rule. Describe how ionic bonds are formed.
Solution Although either event is possible, a sodium atom is more likely to lose its single valence electron. Answer The process that involves less number of electrons is more favorable.
Key Takeaways Atoms have a tendency to have eight electrons in their valence shell. The attraction of oppositely charged ions is what makes ionic bonds. Exercises 1. What is the octet rule?
How are ionic bonds formed? Why is an ionic compound unlikely to consist of two positively charged ions? Why is an ionic compound unlikely to consist of two negatively charged ions? Answers 1. Negative charges repel each other also. Helium liquefies at 4. Some materials become superconductors when immersed in liquid helium; in these materials, there is no resistance to the flow of electricity.
Superconducting magnets are used for an important medical imaging technology called Magnetic Resonance Imaging MRI , which allows images of tissues and organs to be obtained. A related technology is used by chemists to obtain information that can be used to deduce the structures of molecules; this technique is called Nuclear Magnetic Resonance NMR ; the two technologies are basically the same, but the term "nuclear" is avoided in the medical application because of its unpleasant associations even though there is no nuclear radiation involved.
Helium is also used in blimps, where the combination of being lighter than air and nonflammable makes it much safer than hydrogen as demonstrated in the explosion of the Hindenburg.
It is also used in deep-sea diving, since helium is less soluble in the bloodstream than nitrogen, and reduces the risk of the diver suffering nitrogen narcosis, high pressure nervous syndrome HPNS , or the bends.
Breathing helium gas causes the voice to become higher pitched because helium is less dense than air, changing the frequency of the sound waves generated in the larynx. Neon is a colorless, odorless, unreactive gas which liquefies at Neon was discovered in by Sir William Ramsay see entry on Argon below and his assistant Morris Travers while working with a sample of krypton. The name comes from the Greek word for "new," neos. It is found in the Earth's crust at a concentration of 70 ppt, making it the 80th most abundant element; it is found in the atmosphere at a concentration of 18 ppm by volume.
Neon which is used commercially is extracted from liquid air by fractional distillation. Neon is used primarily in neon lights ; stimulating neon with electricity causes it to emit an intense red light. Other noble gases are used in "neon lights" as well, to produce different colors. Neon is also used in some underwater breathing mixtures; liquid neon is used in low-temperature cooling.
Argon is a colorless, odorless, unreactive gas which liquefies at It is found in the Earth's crust at a concentration of 1. Argon which is used commercially is extracted from liquid air by fractional distillation.
Argon had been observed before by Henry Cavendish in , but it had not been identified as an element. Because of its unreactivity, it was named for the Greek word for "idle," argos. When argon was discovered, it didn't fit with the reactivities of any other element on the periodic table, and chemists realized that there might be a whole family of previously-unrecognized elements, which we now recognize as Group 8A.
Argon is used in light bulbs because it is inert to the hot metal of the bulb filament; the filament would burn out much faster in air or even pure nitrogen. It is also used in metal refining, some "neon" lights argon produces a blue light , some food packaging to provide an inert atmosphere to reduce spoilage , in the tires of some luxury cars in place of air, and in lasers used in eye surgery.
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