题目

日常生活中许多现象与氧化还原反应有关，下列现象与氧化还原反应无关的是A. 钢铁生锈 B. 充有H2的“喜羊羊”娃娃遇明火发生爆炸C. 食物腐败变质 D. 大理石雕像被酸雨腐蚀毁坏 答案：【答案】D【解析】由发生的化学的反应可以知道，若存在元素的化合价变化，与氧化还原反应有关；若不存在元素的化合价变化，与氧化还原反应无关，以此来解答。A. 钢铁生锈生成氧化铁，Fe、O元素的化合价变化，为氧化还原反应，故A不选；B.氢气爆炸生成水，H、O元素的化合价变化，为氧化还原反10．Freedom means many things to many people．When we spoke to some children in the age group of 8to 12，we were amazed to learn the different meanings they gave to that one word"freedom"．Here they put their ideas exactly the way their thoughts arose in their minds…I don't have to study．There's no homework over the weekend and on vacation．""Being able to watch my favorite channel Star Plus，Cartoon Network whenever I like．""Eating as many ice creams as I want．""Going for school tours．Only 4th and 5th class students go for tours．We 3rd class students are not allowed．""Not getting up early in the morning．""Doing what I like but should be right …""I will never do anything bad against rules like corruption．""I won't go against the government rules only of the rules are right．Out of 100 percent if 80 percent say a rule is bad then it is bad．""We can do anything we want，like not going to school．""Everything should be free．We should not pay money to buy anything．""Can go anywhere I want …to the playground when exams are on．""Chatting on phone with classmates or friends as long as I want．""In school being able to play sports and not study．""Flying kites．"50．What does Radhika want for freedom？DA．Studying at home．B．Doing homework．C．Going sightseeing．D．Eating more ice creams．51．From the passage we knowC don't want to study．A．Radhika Jain，Arihant Jain and SaloniB．Arihant Jain and SaloniC．Radhika Jain and Arihant JainD．Saloni and Radhika Jain52．What might be the best title for the passage？BA．Speaking for All YourselvesB．Different Ideas about FreedomC．Freedom Is Everything You LikeD．What Are You Thinking about．