（3分）宇宙飞船内，宇航员所呼出的气体要通过盛有氢氧化锂的过滤网，以除去所含的二氧化碳，其反应的化学方程式为：2LiOH+CO2=Li2CO3+H2O。计算吸收44 g二氧化碳需要氢氧化锂的质量。
48克
题目分析：根据化学方程式计算即可。
解：设吸收44 g二氧化碳需要氢氧化锂的质量是X。
2LiOH+CO2=Li2CO3+H2O
48 44
X 44g
48：44=X：44g
X=48g
答：吸收44 g二氧化碳需要氢氧化锂的质量是48g。
点评：根据化学方程式计算，要注意解题的步骤，设、写、找、列、解、答。
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