Solid elements,coded as G,J and Q,belong to the same period of the periodic table,and form oxides with the following properties:GO3 reacts with water to form a strongly acidic solution,J2O3 reacts with strong acids and strong alkalis,Q2O reacts with water to form a strongly alkaline solution.(a)State which oxide would be described as amphoteric.(1 mark)(b)State,giving reasons,which of G,J or Q is most electronegative.(2 mark)(c)State,giving reasons,which oxide is molecular.(3 mark)解答:G为S(硫),J为Al(铝),Q为Na(钠)。(a)Al2O3为两性氧化物,既可与强酸反应,又可与强碱反应。(b)一般来说,周期表从左到右,元素的电负性逐渐变大,而从上到下,元素的电负性则逐渐变小,所以电负性最大的是硫元素,其次是铝,最小的是钠。(c)常温下SO3为气体,Al2O3为固体,Na2O为白色略黄状粉末,所以分子型氧化物是SO3。备注:原来经历过的事情都不会忘记;说忘记的,是一时半会记不起罢了,但仔细去回想却还是能想起来的,比如曾学到的知识、遇过的人以及此时囊中羞涩,兜里没钱,穷到吃土。