[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-112-1-fire-science-037":3},{"subject":4,"subjectSlug":5,"subjectKicker":6,"subjectShort":7,"question":8,"related":27,"sameNumber":52,"hasEssay":26},"火災學概要","fire-science","火災學 · Fire Science","火災學",{"id":9,"webId":10,"year":11,"session":12,"subject":4,"number":13,"stem":14,"options":15,"answer":20,"answerNote":21,"images":22,"imagesPending":23,"lawTimestamp":11,"explanation":24,"explanationDeep":25,"freq":12,"indexable":26},"fire-112-1-火災學概要-037","fire-112-1-fire-science-037",112,1,37,"升高環境溫度對於環氧乙烷的分解爆炸有何影響？",{"A":16,"B":17,"C":18,"D":19},"提高分解爆炸的起爆能量","擴大可發生分解爆炸的濃度範圍","提高可發生分解爆炸的濃度上限","提高可發生分解爆炸的濃度下限","B",null,[],false,"本題考點：環境溫度上升對環氧乙烷分解爆炸濃度範圍的影響，兼辨分解爆炸與氧化爆炸的差別。\n【正解理由】環氧乙烷屬三員環的環醚，環張力使分子不安定，在無氧狀態下即可自行分解放熱而爆炸，此即分解爆炸；乙炔、聯胺、有機過氧化物與臭氧亦屬具分解爆炸性的物質。依爆炸界限隨溫度變化的通則，溫度升高使分子平均動能增加，反應鏈的起始與傳播更容易，能維持分解火焰傳播所需的最低濃度隨之下降，可發生分解爆炸的濃度範圍因而向低濃度側擴大，故選 B。\n【逐項排除】\n(A) 溫度升高等於預先提供部分活化能，起爆所需能量下降，並非提高。\n(B) 正確：下限下降使可爆濃度範圍變寬，這是溫度升高最直接的效果，同一通則亦適用於一般可燃氣體的爆炸界限。\n(C) 分解爆炸不需氧氣，純環氧乙烷本身即可分解，上限已在純物質端而無上調空間。\n(D) 溫度升高使下限下降而非提高，方向相反。\n【記憶點】溫度上升＝爆炸範圍變寬；環氧乙烷連純物質都能自行分解，關鍵在下限往下掉。","一般所稱的爆炸多指可燃物與氧化劑反應的氧化爆炸；分解爆炸則是物質本身在無氧狀態下自行分解、放出大量熱與氣體所致，常見於乙炔、環氧乙烷、聯胺、有機過氧化物與臭氧等分子內能較高的不安定物質。環氧乙烷的分子式為 C2H4O，三員環的鍵角受迫使其熱力學上不穩定，受熱或受激後可分解為甲烷、一氧化碳等產物並放熱，因此即使在完全沒有空氣的容器內，只要達到起爆條件仍可能爆炸，這是它與一般可燃氣體最大的差別。\n爆炸界限隨環境條件變動的通則為：溫度上升時分子平均動能增加，較低濃度即足以維持火焰傳播，爆炸下限下降，上限亦略為上升，整體範圍變寬；壓力上升時，上限的擴張通常比下限明顯。對環氧乙烷而言，因分解反應不需氧氣，可爆濃度的上端可延伸至純物質，溫度升高後主要表現為下限往低濃度側移動，因而「範圍擴大」是最完整的描述，「上限提高」則無從發生。\n易混淆概念可對照記憶：氧化爆炸需要氧化劑，以惰性氣體稀釋、降低氧濃度即可抑制；分解爆炸不需氧化劑，單靠降低氧濃度並不足以保證安全，還須控制溫度、壓力與可能具觸媒作用的雜質。乙炔即為典型例子，鋼瓶內以多孔物質與丙酮溶解乙炔，正是為了避免高壓下的分解爆炸；同理，環氧乙烷的危險性也不會因為容器內抽真空或以氮氣置換而完全消失，溫度與壓力才是決定其是否達到起爆條件的主要變數。\n延伸考點包括：爆炸界限受溫度、壓力、惰性氣體含量影響的方向；勒沙特列公式用於混合可燃氣體爆炸界限的計算；以及分解爆炸、氧化爆炸、粉塵爆炸與蒸氣爆炸在成因分類上的差異。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-112-1-fire-science-036","下列那一種措施有助於提高粉塵爆炸的防護作用以增加其安全性？",36,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-112-1-fire-science-038","當外部風的風向不變而風速加倍時，對處於煙囪效應下的大樓而言，下列敘述何者正確？",38,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-112-1-fire-science-035","相較於氣體爆炸，一般的粉塵爆炸具有下列那種性質？",35,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-112-1-fire-science-039","假設定量乙醇(C2H5OH)與理論空氣量混合後產生完全燃燒，其後將燃燒廢氣冷卻至常溫，則其中二氧化碳的濃度約為多少%？",39,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-112-1-fire-science-034","對於具有分解爆炸性質的可燃性氣體，下列敘述何者錯誤？",34,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-112-1-fire-science-040","已知距離光源 2 公尺處的減光率為 20%，則當與光源的距離加倍時，其減光率約為多少%？（提示：log(80)≒ 1.903，log(64)≒ 1.806）",40,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-113-1-fire-science-037",113,"主成分為碳酸氫鉀的乾粉滅火藥劑不適用下列何種火災？",{"webId":58,"year":59,"stem":60,"number":13},"fire-111-1-fire-science-037",111,"存放乙醇倉庫發生火災，下列那一種泡沫滅火劑較適當？",{"webId":62,"year":63,"stem":64,"number":13},"fire-110-1-fire-science-037",110,"有關電氣火災防範對策中，電器設備之正確使用非常重要，在潮濕場所使用電器時，插頭應加裝何種裝置以防止感電發生？",{"webId":66,"year":67,"stem":68,"number":13},"fire-109-1-fire-science-037",109,"D 類火災可使用的滅火劑，何者適合？",{"webId":70,"year":71,"stem":72,"number":13},"fire-108-1-fire-science-037",108,"下列有關 GHS 制度之說明，何者錯誤？",1785129966639]