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The dissolution process causes a drop in pressure, which draws water into the flask, creating a fountain-like effect.

A compound produced from calcium carbide and water, acetylene burns with a sooty flame.

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.

板块构造是关于板块运动的理论。

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.

山毛榉一词是指生长于从北美到亚洲，例如，遍布北温带的的若干个树种。

你有没有想过你丢进垃圾箱里的垃圾究竟会怎样？

白鹳是欧洲最著名的候鸟之一。 您对这些鸟了解多少呢？

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。

在此视频中，您可以看到用曙红燃料着色过的水是如何在康乃馨中移动的。

当在室温下柔软的物体冷冻到 零下196°C 时，它们会变脆。

观察一个放大100倍的天竺葵的表皮细胞和气孔。