Nikon 35mm vs 50mm lens for portraits?

I'm 18 and just starting out in photography. I have a Nikon D3100 and am going to take senior pictures for people, because I have a natural ability for that kind of stuff. I had called my local camera store and had them order me the Nikon 35mm 1.8f lens, but was reading online that a lot of people are saying that the 50mm is better? I've seen the 50mm 1.8f retail for $150 and the 50mm 1.4f, for a little more. Around $350.
Can I get some input on what you think is the best for portrait photography? Such as senior pictures? I do have the 18-55 kit lens and a 55-200, but I liked the idea of the different style of lens.

The 35 mm lens is far too wide

You need a medium telephoto lens like the AF-S 50 mm

You can test this by taping your 18-55 mm lens at 35 mm and shooting head and shoulder shots and then tape it at the 50 mm setting and shooting the same head and shoulder shots

You will notice when using the 35 mm setting that the facial features will be slightly distorted, bigger ears, nose etc, but you will have to look closely to see the difference.

50mm is a good portrait length on a crop sensor. 35 would be the equivalent of a "standard" lens. I have the 50mm f/1.4. Be aware of the very thin DoF when wide open. Just an inch can make the difference between being a great shot and not a keeper.

Hummm… "a natural ability for that kind of stuff" but you are having to ask such a basic question as this?

Yes, you need the 50mm lens, not the 35.

With that camera I'd suggest the 50mm f1.4 for what you want to do. The f1.4 is superior lens, get it.