The radioisotope radon-222 has a half-life of 3.8 days. How much of a 65-g sample of radon-222 would be left after approximately 15 days?

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  14. Chemistry

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  23. chemistry

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    The radioisotope radon-222 has a half-life of 3.8 days. How much of a 98.4 g sample of radon -222 would be left after approximately 19 days?

  27. Chemistry

    The half-life of radon-222 is 3.82 days. If a sample of gas contains 4.38ug of radon-222, how much will remain in the sample after 15.2 days?

  28. Algebra

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  29. physics

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  30. Chemistry

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  31. science

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  32. Math

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  33. nuclear chem

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  35. Chemistry

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  36. chemistry--please check

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  37. half-life

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  38. math

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  39. Chemistry

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  40. physics-Radioactivity

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  41. Physical Science

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  42. physical science

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    The radioisotope radon-222 has a half-life of 3.8 days. How much of a 65-g sample of radon-222 would be left after approximately 15 days?

  47. Chemistry

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  55. chemistry

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  63. chemistry

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  64. Chemistry

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  65. chemistry

    how many half-lives of radon-222 have passed in 11.46 days?

  66. science

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  67. physics

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  68. Chemistry

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  69. Chemistry

    A 1.50- gas sample at 722 and 25.0 contains 7.56 radon-220 by volume. Radon-220 is an alpha-emitter with a half-life of 55.6s

  70. chemistry

    The disintegration of a radioisotope, such as I-131 to Xe-131, is another example of a first-order reaction. It has a half-life of 8.0 days. I-131 -> Xe-131 + e If you start with 1.40 g I-131, how many grams of I-131 will be left after the following days?

  71. Chemistry

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  72. modern physics

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  73. Science

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  74. chem

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  76. physics

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  77. Chemistry

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  78. Chemistry

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  79. chemistry

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  80. Chemistry

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  81. Chemistry

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  82. engineering

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  83. physics

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  84. Math

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  90. earth science

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  91. earth science

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  96. Ap chemistry

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  99. Math

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