下列叙述正确的是（ ）
【分析】A、根据高锰酸钾在加热条件下生成锰酸钾、二氧化锰和氧气，进行分析判断。
B、工业上分离液态空气制取氧气的原理，进行分析判断。
C、根据自然界中植物通过光合作用的原理，进行分析判断。
D、根据人体呼出的气体的成分，进行分析判断。
【解答】解：A、该化学方程式缺少反应条件，正确的化学方程式为
故选项说法错误。
B、工业上分离液态空气得到O2，利用的液态氮和液态氧沸点的不同，没有新物质生成，属于物理变化，故选项说法错误。
C、自然界中植物通过光合作用吸收CO2，释放O2，故选项说法正确。
D、人体呼出的气体中CO2的含量占4.5%左右，氧气含量为16%左右，人体呼出的气体中CO2的含量比O2低的多，故选项说法错误。
故选：C。
【点评】本题难度不大，了解氧气的工业制法、光合作用的原理、人体呼出的气体的成分等是正确解答本题的关键。
Is this factory ______you visited last week?
They won`t allow us ________ at this beach.
We need fifteen more people_____our team to do the job.
He _________ Alice for tenyears.
He lives in a village _____thereare a lot of trees.
The teacher told us that the sun____in the east.
In the past ，he often made his sister____, but now he is often made ___by his sister.
What do you think ______solvethe problem ?
Jack has something important to do this afternoon . so he can’t attend the meeting____.
—How do you study _______ a test?
—I study by working _______ my partner.
