Only if you want salmonella and anal leakage AKA diarrhea
There's no reason why not. Just make sure everything--bowl, beaters, and egg whites--are at room temperature. Some cooks place the bowl of egg whites over the pilot light of a gas stove briefly (a few minutes) to take off the chill from the refrigerator. Be careful when using this method. You don't want to cook the eggs, just bring them to room temperature before beating.
Yes, you do use egg whites
You would use 4 medium egg whites or 5 small egg whites.
Omit the yolks, and try using two egg whites per egg called for. The extra egg white will make up for the moisture lost in the omitted yolk. For instance, if the recipe calls for two eggs, use four egg whites.
if you want to
The most common reason egg whites and sugar will not for stiff peaks is that a bit of egg yolk or oil has come in contact with the egg whites. If the bowl and beaters have a residue of oil from a previous use, that is enough to prevent egg whites from stiffening. Another possibility is that the sugar was added before the whites were partially beaten, or that the sugar was added all at once instead of gradually.
Make merangues.
If a recipe calls for "2 eggs," it means THE WHOLE EGG. If they want you to use the egg yolk only, it will say, "add the yolk of 2 eggs." If they want you to use the egg whites only, it will say, "separate the eggs and beat in the whites." To 'separate' an egg means to separate the yolk from the whites.
Any bowl or utensil that is used when beating egg whites has to be perfectly clean and grease-free. When air is beaten into egg whites, the proteins of the egg white open up, which makes the whites form a semi-solid. If there are any lipids introduced into the egg whites they prevent the whites from forming a semi-solid state by surrounding the proteins of the egg whites and preventing the proteins from opening.
Use the standard flat beater that came with your mixer.
The egg whites don't move and you can make them into peaks. They are very stiff. Make sure you use a metal or glass bowl when beating egg whites they will beat better rather than in plastic.
White? Do you mean egg whites for a meringue icing? If so, you can't substitute for egg whites unless you have purchased powdered egg whites. Do you mean white as a color and flavor? Any color/flavor will do, depending on your taste.