What is a praya a specie of?

A: Anemone
B: Sponge
C: Jelly fish
D: Coral

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

How are isotopes of the same chemical element alike? how are they different?

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