下列叙述不正确的是（ ）
A．直径介于1nm～100nm之间的微粒称为胶体
B．少量植物油和水的混合物中分散质粒子直径比硫酸溶液中分散质粒子直径大
C．Fe（OH）3胶体具有吸附性，能吸附水中的悬浮颗粒并沉降，因而常用于净水
D．一束光线分别通过溶液和胶体时，后者会出现光亮的通路，前者没有
A、因分散质粒子直径在1nm-100nm之间的分散系称为胶体，故A错误；
B、因浊液中分散质粒子直径大于100nm，溶液中分散质粒子直径小于1nm，少量植物油和水形成的分散系是胶体，故B正确；
C、因Fe（OH）3胶体中胶粒带电，杂质也带电，但电性相反，因而可以吸附杂质来净水，故C正确；
D、因胶体具有丁达尔效应，产生光亮的通路，而溶液没有此性质，故D正确；
故选A．
Getting married can be one of the happiest moments in a person’s life. Throughout the world, weddings are very important events. Let’s look at some interesting wedding customs from different countries. For African Americans, it is tradition for the married couple to jump over a broom covered with flowers. This represents the beginning of family life. It is interesting to note that African slaves who were brought to the USA started this tradition. African American couples were not allowed to have a legal marriage, so instead they had a ceremony where the bride and groom jumped over a broom “into marriage”. Making jokes about the bride and groom is a wedding tradition in both France and Germany. In France, this includes making loud noises with pots; in Germany, wedding guests break dishes. Weddings in Germany often last for three days. On Thursday, there is a simple ceremony at a government office noting the official marriage of the couple. Then the couple will have a dinner with family and close friends. On Friday, there is a party. This is when guests break dishes to represent the start of a new life. Then on Sunday, there is a ceremony in a church. In Greece and Italy, people eat special kinds of sweets at the wedding. Both Greece and Italy also have their own special wedding dances, which all of the guests enjoy. In Russia, couples tie a doll to their wedding car if they want to have a daughter, or a toy bear if they want to have a son. In England, it is tradition for the little girls to throw flowers on the ground on the way to the wedding ceremony. The bride and groom walk on these flowers. This represents the hope that the couples will follow the path that leads to a happy life.
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