Granted. Everything in the universe disappears, except for you. You now have absolutely nothing.

I wish for a large solid block of neutrinos.

Wish granted but as neutrinos being a subatomic partical the "large" is very small so you can't really see it.

I wish for something that will not kill me.

You get nothing at all.

I wish for a kilogram block of pure sodium chloride on the ground in front of me.

Sodium chloride does not react with chlorine. The worst that could happen is that it dissolves and makes the water salty.

Granted. I kill you by filling your body with plutonium salts. As a result, you die very slowly and painfully by radiation poisoning.

I wish for a kilogram of depleted uranium metal. It is not radioactive enough to cause harm, and is in a solid block form, so there is no danger from a dust cloud.

Wish granted but someone crashed into your home propelled the depleted uranium metal onto your bed while you were sleeping crushing your body.

I wish for a picture that isn't important.

It's a picture, all right, but it is made of plutonium, uranium and paper.

I wish for ASCII.

All of your computer's text is replaced permanently with hexadecimal ASCII codes.

I wish for a beluga whale.

While you were swimming in the Artic Ocean I deleverd your robotic space beluga whale which ate you. You never did mention what kind.

I wish for a picture that is important. Just to make sure I passed it through a scanner to detect any harmfull elements or weapons or WMD's.

However, what your scanner did not detect was that the picture was printed on a piece of paper that contained a thin sheet of elemental sodium, which was hidden from the scanner by the paper. When you touched the picture, the sodium reacted with moisture from your hands causing the paper to ignite and set you on fire.

I wish for a kilogram of osmium and iridium.