常用燃烧法测定有机物的组成．现取3.2g某有机物在足量氧气中充分燃烧，生成4.4gCO2和3.6gH2O，则该有机物中（ ）（相对原子质量：H﹣1；C﹣12；O﹣16）
A．一定含C，H两种元素，可能含氧元素
B．一定含C，H，O三种元素
C．一定含C，O两种元素，可能含氢元素
D．只含C，H两种元素，不含氧元素
B．
题目分析：4.4gCO2中C元素的质量=4.4g×
×100%=1.2g；3.6gH2O中H元素的质量=3.6g×
×100%=0.4g；则3.2g有机物中C、H元素质量和=1.2g+0.4g=1.6g＜3.2g，因此，有机物一定含C、H、O三种元素；
My dad was a fisherman. He worked hard and stayed out until he caught enough ______ to feed the family nearly every day. When the weather was bad he would ______ me to school. An old truck was used in his fishing business. When we got to the school, he would give me a big ________on the face and tell me to be a good _______. It was so embarrassing for me. I was 12 years old, and my dad would still kiss me goodbye! I remember the day when I decided I was too _______for a goodbye kiss. When we got to the school and came to a stop, he had his usual big smile. He started to lean 倾斜 toward me, but I put my hand up and ________, “No, Dad. ” It was the first time I had ever talked to him that way. He had a surprised look on his face for a long time, and his________started to be wet. He turned and looked out of the windshield 挡风玻璃. “You’re ______,” he said. “You are a big boy—a man. I won’t kiss you any more. ” It wasn’t long after that when my dad went out to ______and never came back. It was a day when most of the fishermen stayed at home except Dad. He had a big family to feed How I wish I had been a man then. If I had been a man, I would ________have told my dad I was too old for a goodbye kiss.
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