题目

某探究性学习小组利用H2C2O4溶液与酸性KMnO4溶液之间的反应来探究外界条件改变对化学反应速率的影响。实验如表所示，下列有关说法中正确的是（ ）实验序号实验温度/K酸性KMnO4溶液H2C2O4溶液H2O溶液褪至无色时所用时间/sV/mLc/mol·L-1V/mLc/mol·L-1V/mLA29320.0250.13t1BT120.0230.1V18 C31320.02V20.15t1 A.配制KMnO4溶液时可用稀盐酸酸化B.若t1<8，则可通过控制变量法由实验A、B探究H2C2O4浓度对化学反应速率的影响并得出结论：增大反应物浓度，化学反应速率加快C.若T1=293K38、阅读下面短文，用括号内所给动词的适当形式填空。(必要时可加助动词或情态动词) Many scientists say that the world (1)       (get) hotter and hotter．If they are right, the ice at the North and South Poles (2)       (melt 融化) eventually, if this (3)       (happen), the sea will rise and may cover most or all of Singapore This (4)        (force) everybody to move to a safer country． We know that the sun (5)       (heat) the earth．The heat from the sun hits the ground, and some of it goes back into the sky However, factories and vehicles(车辆) produce a lot of harmful gases．When the gases rise into the sky, heat from the sun (6)       (come) through them but heat from the ground cannot, it stays near us in the sky and makes the air hotter anti hotter every year．       Scientists call this the “greenhouse effect” because a greenhouse is a small glass building which is hot inside．It (7)       (use) for growing plants in cool countries．Many countries are worried about the greenhouse effect．They (8)       (try) to stop factories and vehicles from (9)       (send) harmful gases into the shy．Scientists are not sure when the world much hotter．Some people say that the greenhouse effect(10)       (start) already anti has begun to affect the world’s weather． 评卷人 得分 五、书面表达 （每空？ 分，共？ 分）