水素（すいそ、suiso）
- hydrogen

The Japanese word 水素 (すいそ, *suiso*) refers to the chemical element hydrogen. It is a colorless, odorless, tasteless, and highly flammable gas. In chemistry, hydrogen is represented by the symbol H. The word 水素 is used in various contexts, including scientific discussions, environmental studies, and discussions about energy sources.水素 can also refer to any substance consisting mainly of 水素, such as 水素 gas.

⚫︎水素は宇宙で最も豊富な元素です。 Translation: Hydrogen is the most abundant element in the universe. ⚫︎水は水素と酸素でできています。 Translation: Water is made of hydrogen and oxygen. ⚫︎水素エネルギーは環境に優しいエネルギー源として注目されています。 Translation: Hydrogen energy is attracting attention as an environmentally friendly energy source.

You would use the word 水素 in situations where you're discussing the element hydrogen or any substances that primarily consist of 水素. This could be in science classes, when talking about fuel cells, or when discussing the properties of water. It is a technical term, so it is often used in conversations with some scientific background.

The word 水素 is primarily written using kanji and read as すいそ in hiragana. There is no alternative way to write it as the kanji is standard for the element. No variations in the okurigana are used.

There aren't direct synonyms for 水素, as it is a specific scientific term. However, you might use related terms such as: ⚫︎水素ガス (*suiso gasu*): Hydrogen gas.

As 水素 refers to a specific element, it doesn't have a direct antonym.

この実験では、水の電気分解により水素と酸素を生成します。 ・Translation: In this experiment, we will produce hydrogen and oxygen through the electrolysis of water. ・Explanation: This sentence explains how 水素 can be produced through a chemical process.

将来のエネルギー源として、水素燃料電池が期待されています。 ・Translation: Hydrogen fuel cells are expected to be a future energy source. ・Explanation: This sentence illustrates the application of 水素 in the context of energy and technology.

The word 水素 is a compound word in Japanese. It's a combination of: ⚫︎水 (*sui*): Water ⚫︎素 (*so*): Element, or "basic component" Thus, 水素 literally means "water element" or "basic component of water," reflecting the fact that hydrogen is a constituent of water.