题目

油炸食物不宜多吃，因为食物长时间煎炸后会产生微量的丙烯醛（化学式为 C3H4O）等有毒物质，损 害人体健康。下列有关丙烯醛的说法中，不正确的是（ ）A. 丙烯醛中碳元素的质量分数约为 64.3% B. 一个丙烯醛分子中含有 8 个原子C. 丙烯醛中碳、氢、氧原子的个数比是 3﹕4﹕1 D. 丙烯醛属于氧化物 答案：【答案】D【解析】A、丙烯醛的化学式为C3H4O，碳元素的质量分数=×100%≈64.3%，选项正确；B、丙烯醛的化学式为C3H4O，故一个丙烯醛分子中含有8个原子，选项正确；C、丙烯醛的化学式为C3H4O，故丙烯醛中碳、氢、氧原子的个数比是 3﹕4﹕1，选项正确；D、丙烯醛的化学式为C3H4O，含有碳氢氧三种元素，属 选择正确的词填空。 am    is    are   do    does    can    don't 1. I ______ a student. My name ______ Li Hong. 2. She ______ my friend. Her name ______ Wang Mei. 3. Where ______ your balls? They ______ under the bed. 4. ______ those apples? Yes, they ______. 5. On Sunday, I ______ watch TV. I must do my homework. 6. ______ her daughter have a nice English name? - Yes, she does. 7. ______ you spell the word? - Sorry, I can't8. ______ his grandparents like him? 9. —Where ______ I?     —You ______ in a new place. 10. —What ______ your uncle love?       —He loves sports.