问题 问答题

苯的同系物中,有的侧链能被酸性高锰酸钾溶液氧化,生成芳香酸,反应如下:

 (R、R′表示烷基或氢原子)

(1)现有苯的同系物甲、乙,分子式都是C10H14.甲不能被酸性高锰酸钾溶液氧化为芳香酸,它的结构简式是 ;乙能被酸性高锰酸钾溶液氧化为分子式为C8H6O4的芳香酸,则乙可能的结构有 种.

(2)有机物丙也是苯的同系物,分子式也是C10H14,它的苯环上的一溴代物只有一种.试写出丙所有可能的结构简式

 .

答案

能被氧化为芳香酸的苯的同系物都有一个共同点:侧链与苯环相连的碳原子上有氢原子,产物中羧基数目等于苯的同系物分子中能被氧化的侧链数目,若苯的同系物能被氧化为分子式为C8H6O4的芳香酸(二元酸),说明苯环上有两个侧链,可能是两个乙基,也可能是一个甲基和一个丙基,而丙基又有两种结构(-CH2CH2CH3

),两个侧链在苯环上的位置又有邻位、间位和对位3种可能,故分子式为C10H14,有两个侧链的苯的同系物有3×3=9种结构,分子式为C10H14的苯的同系物的苯环上的一溴代物只有一种,其苯环上可能只有2个相同侧链且位于对位,或4个相同的侧链.

故答案为:(1)

9

(2)

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     Shoppers who carefully plan their visit to the grocery store can save money on their grocery bills.

    1   

     Shoppers should visit the grocery store on a full stomach by scheduling their trip immediately after

a large meal. If that's not possible, they should find something healthy to eat while preparing a grocery list.   2  

     Although having a list and sticking to it is the most important  factor  in  saving  money, shoppers  

must prepare lists wisely in order to save.   3   Many special buys are announced through the local

newspapers, so buying the "grocery issue"is worth the investment(投资). However, it's important to

remember that many newer, more expensive products first offered through coupons may not yield enough

savings for shoppers to give up the product they usually buy.

        4    Once at the store, the shopper who wants to save money  should  follow  a  few  more  rules.

The shopper should not stay longer than necessary,because bills go up each minute the shopper is in the

store. So, setting a time limit and a cost limit can hold down the bill.    5   If the grocery list is a short one,

some shoppers choose to use the small handheld basket instead of the roomy grocery cart.

A. A carefully planned list should include in season    produce and any items on sale or discounted

     through  coupons (优惠券).

B. Of course, the shopper should stick strictly to the    shopping list and resist the temptation to buy

     additional items.

C. People who are full are less tired and more likely to    buy what they want.

D. Now that the shopper has completed the grocery list,it's time to leave for the store.

E. You should keep your shopping list carefully in case     you can exchange it for coupons.

F. Most shoppers are less persuaded to buy extra goods     when they are not hungry.

G. Shopping when not hungry, sticking to a grocery list,and following a few simple rules will cut

     down the grocery bill.