An investigator can collect hairs they observe visually (with tweezers or by hand), and they can also use clear tape to lift non-visible hair from a variety of surfaces, such as clothing. Other methods of hair sample collection include combing and clipping methods.
Hydrogen gas is produced when dilute hydrochloric acid is added to a reactive metal.
Balanced molecular equation of sodim metal with hydrochloric acid:
2Na(s) + 2HCl(aq) → 2NaCl(aq) + H₂(g).
Ionic equation: 2Na(s) + 2H⁺(aq) + 2Cl⁻(aq) → 2Na⁺ + 2Cl⁻(aq) + H₂(g).
Net ionic equation: 2Na(s) + 2H⁺(aq) → 2Na⁺(aq) + H₂(g).
Sodium is oxidized from oxidation number 0 (Na) to oxidation number +1, hydrogen is reduced from oxidation number +1 to oxidation number 0 (hydrogen gas H₂).
Another example:
Balanced chemical equation: Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g)
Word equation: zinc + hydrochloric acid → zinc chloride + hydrogen gas
More about hydrogen gas:brainly.com/question/24433860
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The two main types of bonds formed between atoms are ionic bonds and covalent bonds. An ionic bond is formed when one atom accepts or donates one or more of its valence electrons to another atom. A covalent bond is formed when atoms share valence electrons.
Answer:
The statement describes a process involved in the evolution of Earth’s early atmosphere would be:
Cyanobacteria transformed carbon dioxide in the atmosphere into oxygen during photosynthesis
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