题目

“You are going abroad and will live there? Oh, wonderful! You are so lucky.”     Perhaps your family and friends said similar things to you when you left home. But is it true all the time? Is your life in the new country always wonderful and exciting? Specialists say that it isn’t that easy to get used to life in a new culture. “Culture shock” (冲击) is the term specialists use when talking about the feelings that people have in a new environment. “There are three stages of culture shock,” say the specialists. In the first stage, the newcomers like their new environme（1）氮肥硝酸铵化学式为NH4NO3．其中N元素的化合价为______，其氮元素、氢元素、氧元素质量比为______．（2）现有一瓶标签如图所示的浓盐酸，请根据标签上的数据回答问题：①要配制165g20%的盐酸，需用该浓盐酸______mL．②为从定量角度认识中和反应，小明同学自行设计并进行了下面实验：（Ⅰ）在小烧杯中倒入8%的氢氧化钠溶液l0g，滴入2滴酚酞试剂后，溶液呈红色；（Ⅱ）另取10%的稀盐酸逐滴滴加到氢氧化钠溶液中，边滴边振荡，随盐酸滴入，溶液颜色逐渐变浅；（Ⅲ）在溶液红色消失瞬间，停止实验．若停止实验时，两溶液恰好反应．请分析小明实验后回答：A、实验中酚酞试剂的作用是______；B、计算出这时共用去稀盐酸的质量是多少？（精确到0.1）