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  • 誰能幫我做這兩道英語科學(xué)題?.

    誰能幫我做這兩道英語科學(xué)題?.
    1.explain the layout of the periodic table.includ these words:groups,periods,atomic number,metals non-metals,metalloids and noble gases.
    2.plutonium has an atomic number of 94.explain why there are no naturally occurring deposits of plutonium on earth.
    英語人氣:698 ℃時間:2019-08-27 14:51:48
    優(yōu)質(zhì)解答
    1 :the periodic table are seperated into periods,there are 4 groups metals,non-metals,metalloids and noble gases.each group's elements all have atomic number which is the number of protons found in th...
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