Short answer. Yes. Article 1562 provides that where goods are bought by description from a seller who deals in goods of that description, there is an implied warranty that the goods shall be of merchantable quality — this applies independently of the separate warranty tied to a stated special purpose.
What the law says
Where the goods are brought by description from a seller who deals in goods of that description (whether he be the grower or manufacturer or not), there is an implied warranty that the goods shall be of merchantable quality.
Civil Code, Article 1562 — Implied Warranty of Fitness and Merchantability. Read the full provision →
A separate warranty from the special-purpose one
Article 1562 sets out two distinct implied warranties, not one. The first applies where the buyer, expressly or by implication, makes known to the seller the particular purpose for which the goods are acquired, and it appears that the buyer relies on the seller's skill or judgment — that one requires you to have communicated a purpose and relied on the seller's judgment. Your question is about the second, separate warranty, which does not carry that same requirement.
The warranty for goods bought by description
The second warranty is the one that answers your question directly: where the goods are brought by description from a seller who deals in goods of that description (whether he be the grower or manufacturer or not), there is an implied warranty that the goods shall be of merchantable quality. Buying goods by description from a seller who deals in that kind of goods is, on its own, enough to trigger this warranty — no special purpose or reliance on the seller's judgment needs to be shown.
Why no special purpose is needed for this one
The two warranties in Article 1562 are framed as separate clauses precisely because they cover different situations. The merchantable-quality warranty is tied to the ordinary transaction of buying described goods from a seller who deals in them — it exists to ensure the goods are of a saleable standard for that description, independent of whatever the buyer's own particular use for them might be.
What merchantable quality generally means
Merchantable quality broadly refers to goods being fit for the ordinary purposes for which goods answering that description are commonly bought and used, and free of defects that would make them unfit to be sold under that same description. Since you bought based only on the seller's description, this is the warranty your purchase falls under — you do not need to have mentioned any special use to be covered by it, and the seller cannot avoid the warranty simply by pointing out that you never described your intended use of the goods.