國中 解答

將一個陶瓷材質的碗放入水槽中,碗內裝有水,碗體為實心,右圖中甲、乙分別為靜止平衡時的假想剖面示 意圖。已知此種陶瓷的密度大於水,根據「碗內外的水面高度」,判斷甲、乙兩張示意圖是否合理?

下列實驗探討鹼的濃度對皂化反應的影響,步驟如下: (1) 準備四份 30 g 的酪梨油。 (2) 配製四杯同體積、不同濃度的氫氧化鈉溶液。 (3) 將四份酪梨油分別都和固定量的乙醇混合,再加入上述的鹼,邊加熱邊攪拌直到溶液出現黏稠狀態為 止,並停止實驗。 (4) 將產物分離出來並測量其質量,結果如表(一): 表一 NaOH(aq)濃度(%) 10 20 30 40 肥皂質量(g) 5.1 20.4 19.8 19.2 從上述資訊,是否可知道鹼的濃度與反應速率之關係?

關於塑膠下列敘述何者正確?

已知聚合物是由數千個以上原子組成的巨大分子,依來源又可分為天然聚合物和合成聚合物。下列關於聚合物的敘述,何者最為合理?

乙醇和甲醚的化學式皆為 C2H6O,但兩者的物理及化學性質皆不相同,請選出正確的敘述:

棉質衣料是由棉花果莢內的纖維素所製得,而絲綢衣料則是抽取蠶絲後編織而得。關於棉質衣料與絲綢衣料的比較, 下列敘述何者正確?

阿哲在老師的引導下探究常見有機化合物的性質。他將裝有酒精、醋酸、乙酸乙酯的三支試管,依序進行 下列步驟,觀察三支試管的反應,設計實驗記錄如下表。試根據本章節所學,判斷下列表格中的紀錄或分 析,何項正確? 甘油 醋酸 乙酸乙酯 各加入 5mL 的水,以玻棒攪拌,充分混合後靜置一段時間,觀察水溶液外觀 甲 以藍色石蕊試紙檢驗 乙 查找課本,寫出化學式 丙 生活應用舉例 丁

關於乾餾,下列何者錯誤?

Who made ORNILUX glass?

What do spiders use to keep birds away from their webs?

Why do birds often fly into glass?

According to the reading, why do people like glass?

What should you NOT do when you see squirrels in school.

What does forgetfulness most likely(可能)mean?

What do squirrels love to do?

There are three dresses here. The pink one is more beautiful than the blue ________

The students listened to their teacher ________ a story about Australia. It was interesting.

________ Judy knows ice cream is not healthy for her, she still buys it.

We felt the house when the strong wind blew last night.

Some of my pocket money from my grandparents.

Sue will pass the test easily if she harder.

There is no TV in my grandma’s house. We plan to get ________ for her.

of the gifts under the Christmas trees are for my family.

The doll is my sister's. It doesn't me.