问题 选择题

下列离子方程式正确的是

A.Cl2通入水中:Cl2+H2O=2H+ +Cl-+ClO-

B.双氧水中加入稀硫酸和KI溶液:H2O2+2H++2I-=I2+2H2O

C.用铜作电极电解CuSO4溶液:2Cu2++2H2O2Cu+O2↑+4H+

D.钢铁发生吸氧腐蚀时,铁作负极被氧化:Fe - 3e- = Fe3+

答案

答案:B

题目分析:A、次氯酸为弱酸,不能拆开,错误;B、过氧化氢具有氧化性,碘离子具有还原性,在酸性溶液中二者发生氧化还原反应,正确;C、铜作电极电解时阳极是铜放电,生成铜离子,,阴极是铜离子放电生成铜,错误;D、铁作负极被氧化为亚铁离子,亚铁离子再被氧气氧化成铁离子,错误,答案选B。

选择题
阅读理解

A youngster’s social development has a deep effect on his academic(学术的)progress. Kids who have trouble getting along with their classmates can end up behind academically as well and have a high chance of stopping attending school. In the early grades especially, experts say youngsters should be encouraged to work in groups rather than alone so that teachers can spot children who may be having problems making friends. "When children work on a project", says Lillian Kate, an educational professor at the University &Illinois, "they learn to work together, to disagree, to think, to take turns and lighten tensions These skills can’t be learned through lecture. We all know people who have wonderful technical skills but don’t have any social skills.”

At certain age, children are also learning to judge themselves in relation to others. For most children, school marks the first time that their goals are not set by a home clock but by the outside world. Just as the 1-year-old struggles to walk, the 6-year-old is struggling to meet adult expectations. Young kids don’t know how to tell effort and ability apart, says Tynette Hills, coordinator(协调员)of early-childhood education for the state of New Jersey. If they try hard to do something and fail, they may conclude that they will never be able to finish a particular task. The effects of obvious methods of comparison such as posting grades, can be serious. Says Hills, “a child who has had his confidence really damaged needs a rescue operation.”

72.The writer seems to think that a kid’s poor relationship with his classmates would _______.

A.have a lot of side effects on his study 

B、develop his independence but limit his brains

C.certainly lead to his stopping attending school  

D.have nothing to do with his progress in a course

73.The underlined word “spot” means ____________.

A.teach      B.help    C.find   D.treat

74.For most children, school makes them understand_________.

A.that social needs and their own needs have nothing in common

B.how they can meet social needs

C.that one’s effort and ability can be two quite different matters

D.that it is society not they themselves that decides their future

75.Which of the following is most unlikely for the writer to do?_______.

A.To talk to students who have mental problems

B.  To help students develop a feeling of self-respect.

C.To announce a student’s scores in public

D.To keep a student from playing alone

76.Which of the following does a student most need according to the passage? __________.

A.Independence and co-operation.

B.Academic success and independent thought.

C.Ability and self-respect.  

D.Socialization and technical skills.