These changing quantities are called variables. A variable is any factor, trait, or condition that can exist in differing amounts or types. An experiment usually has three kinds of variables: independent, dependent, and controlled.
The Inland taipan (Oxyuranus microlepidotus) is considered the most venomous snake in the world with a murine LD50 value of 0.025 mg/kg SC. Ernst and Zug et al. 1996 list a value of 0.01 mg/kg SC, which makes it the most venomous snake in the world in their study too. They have an average venom yield of 44 mg.
The world's most venomous snake, based on LD50, is the inland taipan of Australia. LD50, mostly on rodents, is a common indicator of snakes' toxicity with a smaller resultant value indicating a higher level of toxicity. There have been numerous studies on snake venom with a variability of potency estimates.