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deff fn [24]
2 years ago
10

Which of the following is an example of a safe laboratory procedure?

Chemistry
2 answers:
vitfil [10]2 years ago
5 0

Answer:a. tying back long hair and loose clothing

Explanation:

ollegr [7]2 years ago
3 0
<span>A is the correct answer. Tying back long hair and loose clothing is important so they don’t dangle in flames or liquids that could dissolve or bleach them, for example. The other choices - consuming food and drink from lab wares, touching hot objects without gloves on and inhaling odors - are examples of very unsafe procedures. </span>
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Answer:

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Explanation:

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\mathbf{pka (H_3PO_4) = -log (7\times 10^{-3} )=2.2}

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\mathbf{pka (HPO_4^{2-}) = -log (5\times 10^{-13} )=12.3}

The reason while option D is the best answer is that, the value of pKa for both

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Using Henderson-Hasselbach equation:

\mathbf{pH = pKa + log \Big( \dfrac{HPO_4^{2-}}{H_2PO_4^-} \Big)}

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<u>Answer</u>:

the continents of earth were clustered together in formation that a scientist named Pangaea.

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Explanation:

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