题目

用方框中所给单词的适当形式填空。每词限用一次。 luck whether reduce among tooth 1． Amy usually ________ her pressure by listening to music. 2． Doctors come to school to check students’ ________ and eyes every term. 3． Jack won the first prize in speaking competition. It was his ________ day. 4． Scientists are doing research to find out ________ the medicine is helpful. 5． Spring Festival’s Eve is a time for a special dinner ________ family and friends.16．写出相应的化学反应方程式．（1）铁丝在氧气中燃烧3Fe+2O2$\frac{\underline{\;点燃\;}}{\;}$Fe3O4（2）氯酸钾制取氧气2KClO3$\frac{\underline{\;MnO_{2}\;}}{△}$2KCl+3O2↑（3）电解水2H2O$\frac{\underline{\;通电\;}}{\;}$2H2↑+O2↑（4）碳和水在高温下生成氢气和一氧化碳C+H2O$\frac{\underline{\;高温\;}}{\;}$CO+H2．