Learn Hardcore Russian: Для зарядки телефона я купил новый кабель.

The preposition для always governs the genitive case in Russian. Here зарядка (“charging”) is a noun, so its genitive singular form is зарядки. This construction literally means “for the charging.”

Is зарядки a verb form (a gerund) or a noun here?

It’s a noun. Russian doesn’t have an English-style gerund. Зарядка is a feminine noun meaning “the act of charging” or simply “charging.” We turn it into genitive (зарядки) to work with для.

Why is телефона also in the genitive case?

We’re saying “charging of the phone.” In Russian, the thing being charged is another noun in genitive. So телефон → genitive singular телефона.

Could I use an infinitive construction instead of для зарядки телефона?

Yes. You can say
• Чтобы зарядить телефон, я купил новый кабель.
Both express purpose, but чтобы + infinitive is more verb-focused, while для + noun is more nominal and sometimes feels more formal or concise.

Why does новый кабель stay in the nominative form even though it’s the object of купил?

Russian inanimate masculine nouns have identical nominative and accusative forms. Since кабель is inanimate and masculine, its accusative looks just like its nominative: кабель. The adjective новый follows the same pattern.

How do I know кабель is masculine?

Most Russian nouns ending in a consonant are masculine. Кабель ends in –ль, so it’s masculine. Adjectives and past-tense verbs will agree with that gender.

Can I place для зарядки телефона at the end of the sentence instead?

Absolutely. Russian word order is fairly flexible.
• Я купил новый кабель для зарядки телефона.
This neutral order puts focus on the purchase first; the original order (with the phrase up front) emphasizes the purpose.

Could I omit телефона and just say для зарядки?

You could, but it would sound vague: “for charging.” Adding телефона clarifies that you mean “for charging a phone.”

Why use купил (perfective) rather than an imperfective like покупал?

Купил is perfective, indicating a completed single action—“I bought (it).” If you said покупал, it suggests an ongoing or repeated process—“I was buying” or “I used to buy.”

If I wanted to talk about multiple phones, would I say для зарядки телефонов?

Yes. Телефон → genitive plural телефонов. Use кабель для зарядки телефонов if you mean “a cable for charging phones” in a general or plural sense.