题目

下列客观事实的微观解释正确的是（ ） 选项客观事实微观解释 A品红在热水中扩散比在冷水中快品红分子在热水中溶解度变大 BH2O在通电条件下产生H2H2O分子中有H2 C搅拌能加快蔗糖在水中的溶解搅拌使蔗糖分子在水中溶解更多 DNaOH溶液能导电溶液中存在自由移动的Na+、OH﹣ A．A    B．B    C．C    D．D完形填空。My grandfather dug water wells in Indiana and started his business during the great depression.Although nearly everyone was out of work, people still needed ______ , so he didn’t lack jobs． ______, in those days, it was awfully hard to get paid for what you did. One morning, a farmer showed up with a ______ —a whole side of fresh beef on his shoulder. “I ______ this ought to make us equal on that digging，”he said to my grandfather. Grandfather ______.It was wintertime, so the beef stayed fresh under damp cloth on the cold back porch(门廊). Each day, Nana stepped out onto the porch, ______ good piece of the meat, and carried it into the kitchen ______ it were pure gold.After a few days. Nana noticed the ______ had been moved．She asked grandfather if he had touched the beef. He hadn’t. “Well, then. ”she said. “somebody’s been eating our meat. Do you always lock the back door?” My grandfather told her not to ______. She probably had moved the cloth herself, and had ______ forgotten.This ______ for many days. Nana was ______ that someone was taking their meat, and grandfather just insisted she was ______ things. It wasn’t until much later that we learned the real story.On the morning after grandfather set the meat out on the back porch door, he ______ some footprints near the door. He ______ followed the footprints to where they began. Soon the footprints in the snow led my grandfather to a house he instantly ______.It was the home of a poor single mother with two young children. Grandfather ______ turned around and walked back home. He didn’t say a word about it to anyone.From then on, Nana would carefully ______ the lock on the porch door each night to make sure it was ______ . Then grandfather, after waiting for Nana to go to bed, would return to the porch and ______ the lock again. Nana never knew about the family they were helping to feed that winter.1.A．beef B．water C．money D．food2.A．Otherwise B．Thus C．However D．Besides3.A．payment B．praise C．delivery D．gift4.A．doubt B．claim C．discover D．expect5.A．suspected B．hesitated C．agreed D．argued6.A．selected B．bought C．preserved D．moved7.A．now that B．even if C．as if D．so that8.A．gold B．cloth C．tool D．porch9.A．disappoint B．forget C．interrupt D．worry10.A．suddenly B．simply C．exactly D．rarely11.A．went on B．went over C．went by D．went up12.A．reliable B．accurate C．strange D．certain13.A．understanding B．remembering C．imagining D．enjoying14.A．noticed B．marked C．guided D．chased15.A．quickly B．finally C．curiously D．coldly16.A．convinced B．recognized C．observed D．removed17.A．hopelessly B．quietly C．gradually D．painfully18.A．watch B．control C．mend D．check19.A．safe B．free C．perfect D．open20.A．exchange B．replace C．release D．adjust