I replaced the hot water heater to my house and I now have hot water everywhere in the house except the kitchen sink. All of the other faucets are separate (one hot, and one cold) but the kitchen is a dual (one handle does both). No water comes out of it at all when I turn it to hot. I didn't turn off the shut off to that sink before I started.

Sounds like the valve gate gave way on you. You can see by losing the water line on the hot side under the sink. Make sure you have a pan there. Loosen it just enough to see if you acturally have any water coming to the valve, if you do then time to replace the faucet handle if no water there then it's going to be the valve. Good Luck

Who replaced the water heater? Do you have cold water at the kitchen faucet? What brand is the kitchen faucet? If you do not have cold water at the kitchen remove the aerator and clean. If you have cold water, turn the hot off at the stop valve under the sink off. Remove the supply tube, open valve slightly to see if you have water. If you have water at the valve the blockage will have to be in the faucet itself. Post back for help in disassembly and cleaning of faucet.