Calcium metal granules storage, help?

We have had some feedback from the metals and acid practical, and our calcium granules that were really reactive last week, are not as reactive this week. It is from 1997, but worked really well last week. The teacher has said that maybe it is absorbing moisture so that's why it is less reactive. Does anybody have any suggestions?
 

Peter Sigsworth

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We have had some feedback from the metals and acid practical, and our calcium granules that were really reactive last week, are not as reactive this week. It is from 1997, but worked really well last week. The teacher has said that maybe it is absorbing moisture so that's why it is less reactive. Does anybody have any suggestions?
Keep mine in original bottle sealed and in silica gel desiccator. Still shiny metal and very active.
 
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