Hydrazoic acid was originally prepared by the reaction of aqueous hydrazine with nitrous acid. Other oxidizing agents, such as hydrogen peroxide, nitrosyl chloride, trichloramine or nitric acid, can also be used. In its properties hydrazoic acid shows some analogy to the halogen acids, since it forms poorly soluble (in water) lead, silver and mercury(I) salts. The metallic salts all crystallize in the anhydrous form and decompose on heating, leaving a residue of the pure metal. It is a weak acid (p"K" = 4.75.) Its heavy metal salts are explosive and readily interact with the alkyl iodides. Azides of heavier alkali metals (excluding
Metal Gear Acid a trading card-based system to control the main character's movements and actions. "Acid" in the name stands for "Active Command Intelligence Duel". The cards are not truly collectible, as the game is complete with a single purchase. However, the game does feature deck design and deck optimization elements. The game allows for multiplayer gameplay by wireless ad-hoc connections of two PSPs. Before each round, the player can customize the deck of cards used by the main characters. The majority of the cards are based upon elements spanning the entire "Metal Gear" series, such as weaponry, characters, and even the Metal