试题与答案

身边处处有化学,在我们的日常生活中,许多现象与化学有着密切的关系.请用①盐、②碱

题型:填空题

题目:

身边处处有化学,在我们的日常生活中,许多现象与化学有着密切的关系.请用①盐、②碱、③一氧化碳、④二氧化碳(固)、⑤氧化钙、⑥氢氧化钙、⑦硝酸钠⑧亚硝酸钠的序号选择填空.

(1)可用纯碱除去面团发酵时产生的酸,纯碱属于______类.

(2)据报道,在一些建筑工地食堂由于把______误作食盐用于烹调,多次发生食物中毒事件.

(3)为了防止某些食品受潮,在其包装袋中放人一小袋干燥剂(标有“请勿食用”的警语).这种干燥剂是______.

(4)______可用作致冷剂,用来保藏容易腐败的食物,也可用于人工降雨.

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A, B, C

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