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彤彤 發問於 科學及數學化學 · 1 十年前

groups and periods (extremely urgent)

1) would you like to tell me what are the differences between periods and groups? ( properties) and explain one by one!!!!

2) also , tell me the "" characteristics"" of the perodic table!! ____ the teacher said that the elements changed not in a straight line , for example , one the left hand side is more reactive ,,,, but I don't understand

%%% please answer in your own answer and provide a website please

THX *1000000000000

1 個解答

  • 1 十年前

    1)groups is classify by the characteristics of element. For example,group one element are all metal , both of them dissolved in water and form OH- . All of them are lighter them water. And because they can form alkali solution when dissolved in water,so they can alkali metal. But group is classify by the numbers of layer of electron. And there is no same characterstic in group.

    2)Gropu I ,Alkali metal, Any of a group of soft, white, low-density, low-melting, highly reactive metallic elements, including lithium, sodium, potassium, rubidium, cesium, and francium.

    Group II,Alkaline earth metal,Any of a group of metallic elements, especially calcium, strontium, magnesium, and barium, but generally including beryllium and radium. Also called alkaline earth.

    Group VII,all are toxic element,and they less reactivity when under go the group,so F is the most reactivity to gain electron.

    Grop 0,all are noble gases,The periodic table of elements is ordered by the number of protons in the nucleus of an atom for a given element (the atomic number), yet the chart is also arranged in such a way that elements with similar characteristics are grouped together. Such is the case with Group 8, which is sometimes called Group 18, a collection of non-metals known as the noble gases. The six noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Their atomic numbers are, respectively, 2, 10, 18, 36, 54, and 86.

    Several characteristics, aside from their placement on the periodic table, define the noble gases. Obviously, all are gases, meaning that they only form liquids or solids at extremely low temperatures—temperatures that, on Earth at least, are usually only achieved in a laboratory. They are colorless, odorless, and tasteless, as well as monatomic—meaning that they exist as individual atoms, rather than in molecules. (By contrast, atoms of oxygen—another gas, though not among this group—usually combine to form a molecule, O2.)