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Verdich [7]
3 years ago
9

Classify each of the following pure substances as an element or a compound. a. helium gas (He) b. mercury (Hg) in a thermometer

c. sugar (C12H22O11) d. sulfur (S) e. lye (NaOH)
Chemistry
1 answer:
olga nikolaevna [1]3 years ago
4 0

Answer:

A. Element

B. Element

C. Compound

D. Element

E. Compound

Explanation:

A, B, and D are elements while C and E are compounds. The three are elements backside basically they are yet to bond with any other element to form a compound.

Although the mercury is in glass, this doesn’t change the fact that it is an element. Being in glass does not affect the independence it enjoys as an element. This serves to mean that even elements can be useful in their elemental states and this does not affect their initial state. They still remain as elements even if they are in a particular confinement.

The other two I.e lye and sugar are compounds as they contain more than one element which are mixed together in appropriate volume

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belka [17]

Answer:

r_{H_2}=-2r_{CH_3OH}

Explanation:

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In this case, for the reaction:

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\frac{1}{-1} r_{CO}=\frac{1}{-2} r_{H_2}=\frac{1}{1} r_{CH_3OH}

Whereas the reactants, CO and H2 have negative stoichiometric coefficients; therefore the rate of disappearance of hydrogen gas is related to the rate of appearance of methanol as shown below:

\frac{1}{-2} r_{H_2}=\frac{1}{1} r_{CH_3OH}\\\\r_{H_2}=\frac{-2}{1} r_{CH_3OH}\\\\r_{H_2}=-2r_{CH_3OH}

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7 0
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How many molecules of water are produced by the combustion of 3.00 g of methane
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I) the heat capacity of ammonia(s)

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From 195 K to 0 K, ammonia is solid. To calculate the change of enthalpy in that process we need to know the heat capacity of ammonia(s).

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3 years ago
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