What is the hydrogen ion concentration of a solution ph’s being 4.18??? pls help!!!

Smog is the term used to describe the combination of fog and smoke

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?