短周期元素A、B、C、D的原子序数依次增大.A原子的最外层电子数是内层电子数的2倍，元素B在同周期的

您可能感兴趣的试题

• 1规定的观察期内某病患者中因该病而死亡的频率是A.发病率B.患病率C.某病病死率D.某病死亡率E.治愈

  规定的观察期内某病患者中因该病而死亡的频率是

  A.发病率

  B.患病率

  C.某病病死率

  D.某病死亡率

  E.治愈率

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做
• 2The research carried out in eight countries______.A．reveals the relationship between sleep

  The research carried out in eight countries______.

  A．reveals the relationship between sleep problems and age

  B．provides evidence that lack of sleep affects people"s health

  C．puts forward the theory that sleep problems are a kind of disease

  D．proves that sleep problems will lead to smoking and poor diet

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做
• 3求原因.w,x,y,z,是原子序数依次增大的同一短周期元素,w、x是金属元素,y、z是相邻的非金属元
  求原因.w,x,y,z,是原子序数依次增大的同一短周期元素,w、x是金属元素,y、z是相邻的非金属元素,y的低价氧化物通入z单质的水溶液中能发生反应生成两种强酸.w、x、y、z各是什么?w：Na.x：Al.y：S.z：Cl
  
  点击查看答案进入在线练题题不想做，我帮你做
• 4求高中化学常见的方程式
  求高中化学常见的方程式
  
  点击查看答案进入在线练题题不想做，我帮你做
• 5According to the passage, what problem does the recent research find？A．Sleep shortage has

  According to the passage, what problem does the recent research find？

  A．Sleep shortage has become a worldwide problem.

  B．Developed nations don"t pay enough attention to sleep.

  C．Sleep problems are more serious in developing countries.

  D．Lack of sleep is more obvious in developed countries.

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做
• 6American students usually get their high school diploma at the age of______.A．12B．17C．20D．

  American students usually get their high school diploma at the age of______.

  A．12

  B．17

  C．20

  D．24

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做
• 7高中化学所有重点方程式 帮忙写详情点 谢谢!
  高中化学所有重点方程式 帮忙写详情点 谢谢!
  
  点击查看答案进入在线练题题不想做，我帮你做
• 8What responsibilities do states have concerning education？A．They must decide what certific

  What responsibilities do states have concerning education？

  A．They must decide what certificate teachers should have.

  B．They must pick out the suitable textbooks for students.

  C．They must make sure every child can receive education.

  D．They must provide enough funds for their schools.

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做
• 9高中化学最重要的二十个方程式是什么?
  高中化学最重要的二十个方程式是什么?
  
  点击查看答案进入在线练题题不想做，我帮你做
• 10氰化氢中毒的毒作用特点是A、与血液中Hb结合，影响氧的运输B、血液中Hb虽被氧饱和，但不能被组织利用

  氰化氢中毒的毒作用特点是

  A、与血液中Hb结合，影响氧的运输

  B、血液中Hb虽被氧饱和，但不能被组织利用

  C、抑制体内多种酶的活性

  D、抑制胆碱酯酶的活性

  E、降低脑和肝中ATP酶的活性，使细胞缺氧

  请帮忙给出正确答案和分析，谢谢！

  点击查看答案进入在线练题题不想做，我帮你做