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When acetylene is combined with bleach, a vigorous addition reaction involving flames occurs.

The largest endemic European hornet species, characterised by its venomous sting and its taste for other insects.

猿猴是灵长目脊椎动物，俗称猴子和猿。

Let's learn more about the fascinating history of computing, which has gone through an unprecedented rapid evolution.

Let's learn more about the fascinating history of computing, which has gone through an unprecedented rapid evolution.

These golden-yellow, though poisonous, flowers turn damp meadows into a sea of yellow.

一种常见的森林动物；它是家猪的祖先。

The ginkgo biloba is an ancient tree species that has been around since prehistoric times.

板塊構造是關於板塊運動的理論。

Examination of filamentous plant and fungus species with an optical microscope.

Slovenia is a former Yugoslav successor state inhabited by merely 2 million people. Despite its size, it offers a diverse range of landscapes and climates.

当从果皮提取的精油接触到蜡烛的火焰时，它会燃烧并生成一个火球。

一种令人着迷的水生昆虫种类，能够利用表面张力在水面上“行走”。

Testing the rules of series circuits by modelling.

Testing the rules of parallel circuits by using modelling.

山毛櫸一詞是指生長於從北美到亞洲，例如，遍佈北温帶的的若干個樹種。

你有沒有想過你丟進垃圾箱裏的垃圾究竟會怎樣？

白鸛是歐洲最著名的候鳥之一。 您對這些鳥瞭解多少呢？

让我们观察淀粉酶在卢戈氏溶液存在下对淀粉溶液的影响。

在此視頻中，您可以看到用曙紅燃料着色過的水是如何在康乃馨中移動的。

當在室温下柔軟的物體冷凍到 零下196°C 時，它們會變脆。

觀察一個放大100倍的天竺葵的表皮細胞和氣孔。

讓我們用鹽酸和胃蛋白酶的混合物模擬胃中蛋白質的消化。

觀察吹奏不同長度的排笛發出的聲音會有什麼不同。