题目

The Red Cross is an international organization which cares for people who are in need of help. A man in a Paris hospital who needs blood, a woman in Mexico who was injured in an earthquake, and a family in India that lost their home in a storm may all be aided by the Red Cross.   The Red Cross exists in almost every country around the world. The world Red Cross organizations are sometimes called the Red Crescent, the Red Mogen Daid, the Sun, and the Red Lion. All of these agencies share a common goal of trying to help people in need.   The idea of forming an organization to help the s科学家发现，食用虾类等水生甲壳类动物的同时服用维生素C容易中毒。这是因为对人体无害的+5价砷类化合物在维生素C的作用下，能够转化为有毒的+3价的含砷化合物。通过以上信息填空：（1）维生素C具有 （填“氧化性”或“还原性”）。（2）上述过程中+5价砷类物质作为 （填“氧化剂”或“还原剂”），+5价砷元素发生 反应（填“氧化”或“还原”）；2mol +5价砷完全转化为 +3价砷，共转移 个电子（用NA表示阿伏加德罗常数）。