Answer:
The ancient Greeks believed that there were four elements that everything was made up of earth, water, air, and fire.
Los antiguos griegos creían que había cuatro elementos y que todo estaba compuesto de tierra, agua, aire y fuego.
Explanation:
How does one determine the identity and structure of an unknown compound? This is not a trivial task. Modern x-ray and spectroscopic techniques have made the job much easier, but for some very complex molecules, identification and structure determination remains a challenge. In addition to spectroscopic information and information obtained from other instrumental methods, chemical reactions can provide useful structural information, and physical properties can contribute significantly to confirming the identity of a compound.
In this experiment, you will be asked to identify an unknown liquid, which will be either an alcohol, aldehyde, or ketone. Identification will be accomplished by carrying out chemical tests, called classification tests, preparing a solid derivative of the unknown and determining its melting point (MP), making careful observations, and analyzing the NMR spectrum of the unknown.
OO
Answer:
Half-reactions:
Cr³⁺ + 1e⁻ → Cr²⁺; Zn → Zn²⁺ + 2e⁻
Net ionic equation:
2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺
Explanation:
The Cr³⁺ is reduced to Cr²⁺:
<h3>
Cr³⁺ + 1e⁻ → Cr²⁺ -Half-reaction 1-</h3>
Zn is oxidized to Zn²⁺:
<h3>
Zn → Zn²⁺ + 2e⁻ -Half-reaction 2-</h3>
Twice the reduction of Cr:
2Cr³⁺ + 2e⁻ → 2Cr²⁺
Now this reaction + Oxidation of Zn:
2Cr³⁺ + 2e⁻ + Zn → 2Cr²⁺ + Zn²⁺ + 2e⁻
<h3>2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺ - Net ionic equation</h3>
Because the ring is hollow
