Note that aluminium can be difficult to place in the correct position in the reactivity series during these experiments. This is because its protective aluminium oxide layer makes it appear to be less reactive than it really is. When this layer is removed, the observations are more reliable. It is useful to place carbon and hydrogen into the reactivity series because these elements can be used to extract metals.
Here is the reactivity series including carbon and hydrogen:. Note that zinc and iron can be displaced from their oxides using carbon but not using hydrogen.
However, copper can be extracted using carbon or hydrogen. The reactivity series In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. Category: science chemistry. Answer and Explanation: The noble gas group is the group of elements that are the least reactive. The noble gases are the last column on the right side of the periodic.
Which is the least reactive metal? What is the 2nd most reactive metal? What is the least reactive element in Group 2? What metals are most reactive? What is the most reactive element in Group 1? Which element reacts most vigorously with water?
What makes an element reactive? How can you tell which element is more reactive? What is the least reactive element? Is iodine more reactive than chlorine? Is potassium more reactive than sodium?
What is the least reactive element in Period 4? What is the least reactive element in Group 7? Reactions with water. Which element is the most reactive out of the list below? Reactivity of Group 1 Elements. Which element is more reactive lithium or beryllium?
The skeleton of the average adult contains about a kilogram of calcium. Because calcium—like barium—absorbs x-rays, bones show up white in x-ray images. Calcium is an important component of a healthy human diet. Good food sources of calcium are pictured in Figure below.
People with osteoporosis are at high risk of bone fractures. Strontium is a silver-colored alkaline Earth metal that is even softer than calcium.
Strontium compounds are quite common and have a variety of uses—from fireworks to cement to toothpaste. In fireworks, strontium compounds produce deep red explosions.
In toothpaste, like the one pictured in the Figure below , the compound strontium chloride reduces tooth sensitivity. They are silvery or gray in color. They are also relatively soft and low in density. Reactivity increases from the top to the bottom of the group.
At the following URL, observe how four different alkaline Earth metals react with water. After you watch the video, answer the questions below.
Observe the reactions in the video, and then rank the alkaline Earth metals from most to least reactive with water. Predict the reactivity of beryllium with water. Where would it fit in your ranking? What substances are produced in each reaction that you observed in the video? What are alkaline Earth metals? What are their physical properties? Compare and contrast the reactivity of beryllium Be and barium Ba.
This fanciful picture serves to make the point that helium is one of the lightest elements. Helium belongs to a group of elements called the noble gases. Noble gases are nonreactive, nonmetallic elements in group 18 of the periodic table. As you can see in the periodic table in Figure below , noble gases include helium He , neon Ne , argon Ar , krypton Kr , xenon Xe , and radon Rn.
All noble gases are colorless and odorless. They also have low boiling points, explaining why they are gases at room temperature. Radon, at the bottom of the group, is radioactive, so it constantly decays to other elements. For an excellent overview of the noble gases, watch the video at this URL:. Q: Based on their position in the periodic table Figure above , how many valence electrons do you think noble gases have?
A: The number of valence electrons starts at one for elements in group 1. It then increases by one from left to right across each period row of the periodic table for groups 1—2 and 13— Therefore, noble gases have eight valence electrons. Noble gases are the least reactive of all known elements. The only exception is helium, which has just two electrons. But helium also has a full outer energy level , because its only energy level energy level 1 can hold a maximum of two electrons.
A full outer energy level is the most stable arrangement of electrons. As a result, noble gases cannot become more stable by reacting with other elements and gaining or losing valence electrons. Therefore, noble gases are rarely involved in chemical reactions and almost never form compounds with other elements.
Noble Gases and the Octet Rule. Because the noble gases are the least reactive of all elements, their eight valence electrons are used as the standard for nonreactivity and to explain how other elements interact.
According to this rule, atoms react to form compounds that allow them to have a group of eight valence electrons like the noble gases. For example, sodium with one valence electron reacts with chlorine with seven valence electrons to form the stable compound sodium chloride table salt.
In this reaction, sodium donates an electron and chlorine accepts it, giving each element an octet of valence electrons. Did you ever get helium balloons like those in the opening picture? A: Helium atoms have just two protons , two neutrons , and two electrons, so they have less mass than any other atoms except hydrogen.
As a result, helium is lighter than air, explaining why a helium balloon floats up into the air unless weighted down. The filaments quickly burned out.
Oxygen in the small amount of air remaining inside the light bulb reacted with the metal filament. This corroded the filament and caused dark deposits on the glass.
Filling a light bulb with argon gas prevents these problems. This protects the filament and keeps the glass blub free of deposits.
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