If we randomly sampled *200* Boron isotopes from nature, how many would be Boron-11? 160

How to solve 4 nh3(g) + 5 o2(g) > 4 no(g) + 6 h2o(g) in chemistry

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

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