小明在“探究平面镜成像的特点”的活动中所选用的器材和活动过程．

    My name is Sam. I am a junior high school student. My school is close to my home, so I always go to school on foot. Classes start at 8 a.m., and I am seldom late. I like Geography best. I enjoy learning about different places in the world.

    In the morning, we usually study Chinese, Maths and English. We have our morning break at 9:50 a.m..  When the bell rings, I run to the playground with my best friends Tom and Jack. We often play games. Break ends at 10:10 a.m..

Lunch is from 11:50 a.m. to 12:30 p.m.. Afternoon classes end at 3:30 p.m. Then Tom, Jack and I take part in the school bank practice. We make great music together.

    I always have a good time at school.

①酸碱中和反应生成盐和水，所以生成盐和水的反应一定是中和反应；

②氧化物中含有氧元素，所以含有氧元素的化合物一定是氧化物；

③金属铝与盐酸反应生成AlCl₃和H₂，所以金属铁与盐酸反应生成FeCl₃和H₂；

④浓硫酸具有吸水性，所以浓盐酸也具有吸水性．

⑤溶液中有晶体析出，其溶质质量减小，所以溶质的质量分数一定减小．