Arrange Boron, Nitrogen and Aluminium in increasing order of atomic radius and explain​

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

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?

Consider the reduction reactions and their equilibrium constants. cu+(aq)+e−↽−−⇀cu(s)pb2+(aq)+2e−↽−−⇀pb(s)fe3+(aq)+3e−↽−−⇀fe(=6.2×108=4.0×10−5=9.3×10−3 cu + ( aq ) + e − ↽ − − ⇀ cu ( s ) k =6.2× 10 8 pb 2 + ( aq ) +2 e − ↽ − − ⇀ pb ( s ) k =4.0× 10 − 5 fe 3 + ( aq ) +3 e − ↽ − − ⇀ fe ( s ) k =9.3× 10 − 3 arrange these ions from strongest to weakest oxidizing agent.