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化学 高校生

解法が3つあるのですが、これら全てできるようにしておいた方がいいのでしょうか?

例題2 燃焼熱 プロパンCaHaの熱焼熱を求めよ。 ただし, プロパン (気), 水(液), 二酸化炭素(気) の生成熱をそれぞれ105kJ/mol, 286kJ/mol, 394kJ/mol とする。 解法I…熱化学方程式の加減乗除 解法I…生成熱の差が反応熱に等しいことを利用 (解説) 解法I 熱化学方程式をつくり, 加減乗除して解く。 poln/ 解法I…エネルギー図を利用 与えられた生成熱を用いて熱化学方程式をつくる。 プロパンの生成熱 3C(黒鉛)+ 4He (気) =D CaHa (気) + 105kJ 水の生成熱 Ha(気) +-02(気)=DH:0 (液) + 286kJ …2 二酸化炭素の生成熱 C(黒鉛)+ O2(気)=D C02(気) + 394kjJ 求める反応熱を [kJ/mol]として, 熱化学方程式を書く。 プロパンの燃焼熱 CaHe (気)+ 502(気) =D 3C02(気)+4H:0 (液) +Q[kJ] ①~③式を用いて、 ①式を組み立てる。(必要な物質だけを集めていく。) まず、1つだけ出てくる物質に注目して集めるようにする。 CaHa (気)は①式, Ha0 (液夜)は 2式,CO2(気)は③式のみに含まれる。CaHe (気)は①式の右辺に含まれるが, 求める式では 左辺に含まれることになるので, -1倍して加える。なお, 複数の熱化学方程式は, 連立方 程式を解くときと同様に,加減乗除ができる。 0x(-1) -3C(黒鉛)- 4H2(気)= -CaHa (気)- 105kJ 2×4 4H2(気)+ 202(気) =D 4H:0 (液) + 286kJ×4 3C(黒鉛)+ 302(気) = 3C02(気)+ 394kJ×3 502(気)= 3C02 (気)+ 4H:0 (液)- CaHe (気) +(-105kJ) +286kJ×4+394k]×3 3×3 これを整理すると, CaHa(気)+ 502(気) = 3C02(気) + 4H20 (液) + 2221kJ 解法I エネルギー図を用いて解く。 解法Iの0~をエネルギー図で表すと右図のようになる。 したがって, 反応熱Q[kJ/mol]は, Q=394kJ×3+ 286KJ×4-105kJ= 2221 k] 解法I 生成熱と反応 熱の関係式に代入し て解く。 反応熱=生成物の生成熱の総和一反応物の生成熱の総和 の関係を用いると, 高 単体 3C+4H2+502 105kJ 反応物 CaHa+50z 熱化学方程式とエネルギー図は 対応して考えられるようにする。 の×3 394kJ×3 ,3C02+4H2+202 Q[kJ] CaHa(気)+ 502 (気) = 3C02(気) + 4H20 (液) +Q[kJ] 2×4 286KJ×4 Q=394kJ×3+ 286kJ×4-105kJ=2221 kJ (注意)単体の生成熱は、 生成熱の定義から0となる。 生成物 3C02+4H.O 2221kJ/mol HRニサー

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英語 中学生

過去問なんですが答えを貰っておらず分からないので教えてください よろしくお願いします

9 次の英文を読んで、後の問いに答えなさい。 Naln was an 'exchange student from *Tndonesia at Minami High School. Her class was going to nave class activities about Indonesia Nani was asked to introduce some games to play. She thought, “I have an idea. I will introduce a game like Japanese janken. One day after school, Nani was on her way home. It began to rain. She was lucky because she was carrying her pink umbrella with her. She went to a convenience store to buy some "snacks. She Ctered the store and put her umbrella near the door There were some other umbrellas there. When she was looking for some snacks, she saw a tall girl. The girl went out through the door. Nani bought some "pieces of bread and a *pack of orange juice. She found one pink umbrella near the door, but it wasn't hers. She said to herself, "Someone has taken( ). Nani said to the Clerk, "T can't find my umbrella. I put it here but " The clerk thought "for a while and said, "1 guess my daughter, Kumiko, took yours "by mistake. Our shoD is very small, and our “family members Sometimes use that door. Kumiko hurried to her friend's house to return a book. She will be back SOon. Nani said, "No problem." The clerk looked at her uniform and said, "Oh, you are a Minami High School student. Kumiko was a student there, too." Nani said, "My name is Nani. I'm from Indonesia." A few minutes later Kumiko came back and her mother said to her, "Kumiko, this is Nani. You took her umbrella. Both of yours are pink." Kumiko said, "Oh, I'm sorry." Her mother said, "She is an exchange student from Indonesia at Minami High School." Kumiko said, "I was a student there too. Nice to meet you. When I was a student, I was very interested in foreign countries. I wanted to have a friend like you. Did you tell your classmates about your country? Nani said, "Yes, but I want to teach them more. I'm going to introduce Indonesian janken to my classmates. I hope they will enjoy it." Kumiko smiled and said, "A game? That's interestingl I'm interested in it. I'd like to see it. Would you like to come to my room?" Nani said, They went up to Kumiko's room. Nani said, "Ill teach you a game, Suit, from my country. It's like a Japanese janken. This is how to play it. You are three "fingers, a *thumb, a “forefinger and a *little finger. A thumb means an elephant. A forefinger means a man. A little finger means an ant. An elephant is stronger than a man. A man is stronger than an ant. An ant is stronger than an elephant." Kumiko asked, "Why is an ant stronger than an elephant?" Nani answered, "An ant goes into its ear, and the elephant cannot do anything about it. The elephant feels very bad. Do you 1understand?" Kumiko said "Yes, I do. I think it is not difficult to understand this game." Nani was glad to hear that. They played it together. After the first game, they tried it again. Kumiko won the second game. They tried it many times. They had a good time. Kumiko said to Nani. "Thank you for teaching me such an interesting game. Im sure your classmates will be excited too." Two days later, Nani's class had class activities. When Nani introduced the game to her classmates, they were interested in it. I hey enjoyed playing it many times. They had a great time. (注*) exchange student 交換留学生 Indonesia インドネシア snack 軽食 piece 一切れ pack パック for a while しばらくの間 by mistake 間違って family member 家族 thumb 親指 forefinger 人差し指 little finger 小指 finger 指

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