According to Google Translate, "yellow" translates to "黄色" (Huáng sè).
What is the meaning of "Huáng" alone? Does it make sense used as a pet name? Or is it silly?
What about the other colors names "red", "green", "blue", "purple", "orange"?
Please consider I know nothing about the language: forgive me if my question is stupid.
黄 has two uses - indicating the color yellow, and the surname of a person. You can give any name to your pet, including 黄, but it sounds odd, and people might miss it for 皇 (emperor).
You can call him "小黄", or "大黄", then it is fine, especially when it matches his color.
You can also nickname your pet "老黄", but better to avoid calling him in crowded public, as everybody will try to figure out who the "person" is. :)
黄 = yellow 色 = colour
So goes all other colours in Chinese.
红色 = red colour
So you can say a red car as 红车 or more lengthily 红色车 or 红色的气车。
Given r13's answer (which is correct) I would definitely find a single Huang to be a weird pet's name. Probably 黄黄 (2 intonation, 4 intonation to call out) is acceptable for pets, kinda like a name you might call a young child at home. Matter of opinion but I'd also find 大黄 a bit suggestive of the pornographic meaning :)
大黄, a widely used name for pet dog.