阅读短文，下列问题。

      Helen Keller lived in the US. She was a great woman. When Helen was a baby, she often got ill. After a few years, she heard nothing, she saw nothing, and she couldn’t speak to other people.

     When one day, a teacher came to live with Helen and her family. The teacher helped Helen learn about words. Helen was a bright child and soon she learned to spell her first word. When she was older, she went to college（大学）.

     Helen was very famous. She helped many blind and deaf people. She went around the world and helped many people.

Helen was a very old woman when she died. Today, the world remembers her. She was blind and deaf, but she found a way to see and to hear.

下面句子中加横线的词语，使用不恰当的一项是（）

某学习小组在做氢气还原氧化铜的实验时，在试管内加入氧化铜固体10克，通入氢气一会儿后再给氧化铜加热，反应完全后撤去酒精灯并停止通入氢气，在空气中将试管冷却，发现部分红色团体又变回黑色.称得试管中剩余固体质量为8.4克。