Nikon 50mm F1.8G or Nikon 35mm F1.8g?

I have a Nikon d3100 with the beginners kit 18-55mm
i've been thinking of buying one of those 2 but which one should i buy
i love to do portraits and landscapes
also what's the difference cause i'm still a beginner

You can set your 18-55 lens to 35mm and then to 50mm and check which of these 2 prime lenses do you like more. In terms of quality and optics, I would choose 50mm. It also has a better (less aggressive) bokeh than 35mm 1.8G.

If you are interested in portraits, between these two, 50mm is more suitable. With the crop factor of 1.5 times, it would be like 75mm. However, if you like landscape, probably your 18-55mm lens will do a better job since you mostly will need a wider focal range.

He's right, the 50mm is great for portraits and the short end of your zoom does brilliant landscapes.

The 35mm makes a useful standard lens, but doesn't have the flexibility of the zoom you already have.

Of the two, the 50mm lens would be better for portraiture. For landscapes, your kit lens will be better than the 35mm lens.

One issue with a 35mm lens is that while it "appears" like a 50mm lens on a cropped camera such as your D3100, it retains the perspective distortion of the 35mm lens. The reason is that the lens is still a 35mm lens, whether or not it is cropped.

For that reason, it is not that good for portraiture. Check out this webpage comparing the 35mm and 50mm lenses. Notice the perspective distortion of the 35mm lens. While it is slight, it is still there.

http://www.althephoto.com/lenses/35mmprime.php

Perspective distortion results in the appearance of round faces and big noses, not the best thing for portraiture.

I used to own the 35mm lens, and in my opinion, it is not a lens you would use that much. I also have a 50mm lens (f/1.8 D) and I always used it over the 35mm lens.

I would go for the 50mm lens.

Nikon 50mm will be great for portraits. I do freelance event/portrait/fashion photography as a side job. I currently own and actively use two Nikon D90's (DX crop sensor bodies). I usually have one body with a 35mm f1.8G for landscape or indoor group (close quarters) photography and another body with either a 50mm f1.8G or a 70-200mm f2.8G VR2 depending of the amount of reach I would need during the photo shoot.
That says a lot about the 50mm f1.8G. I get photos with edge to edge sharpness, color and contrast close to my pro-grade tele-zoom lens plus an extra kick on low light and shallow depth of field when it's needed for a fraction of the price. The bokeh and optics is a great improvement from the 50mm f1.8D which I still own and hardly use anymore. For 50mm f1.8D owners, I would recommend upgrading to the G version if you love working around the 50mm focal length and if you hardly use apertures beyond f16.