. How much time would it take for a 25.2 gram sample of Technetium-99 (half life = 2.13 x 105 years) to contain 3.15 grams of Technetium-99?

Which one of the following gases is not an important component of soil?

Asa choose the correct set of reaction coefficients to properly balance the following chemical equation according to the law of conservation of mass: __s8 + __o2 ==> __so2 1, 1, 8 1, 8, 1 1, 8, 8 8, 1, 1

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture