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Calculate the volume of 12.0 g of helium at 100° C and 1.2 atm.

satela [25.4K]

Answer:

the answer I think is 76.5L

7 0

3 years ago

1.

IRINA_888 [86]

Answer Choice: C

Explanation: Mendeleev is best known for publishing the first periodic table of elements in 1869, revolutionizing the world's understanding of physics and chemistry; and, really almost every aspect of science.

8 0

3 years ago

Butyl butyrate is an ester that is a naturally occurring oil used in the flavor industry for its fruity scent. If the steam dist

Snezhnost [94]

Answer:

The correct answer is 62.5 %.

Explanation:

Based on the given information, the partial pressure of butyl butyrate is 50 mmHg and the partial pressure of water is 710 mmHg.

Hence, the total pressure is 710+50 = 760 mmHg

According to Dalton's law of partial pressure,

Partial pressure = mole fraction * total pressure

Mole fraction of water is,

Partial pressure of water/Total pressure = 710/760 = 0.93

Similarly, the mole fraction of butyl butyrate is,

Partial pressure of butyl-butyrate/Total pressure = 50/760 = 0.07

Therefore, mole% of water is 0.93 * 100 = 93 %

For calculating mass%,

Mass of H2O = 0.93 * 18 = 16.8 grams (The molecular mass of water is 18 grams per mole)

The molecular mass of butyl-butyrate is 144 gram per mole

The mass of butyl-butyrate = 144 * 0.07 = 10.08 grams

The mass percent of water will be,

Mass % of water/Total mass % * 100 = 16.8 / 10.08 + 16.8 * 100 = 62.5%.

8 0

3 years ago

11. In TLC analysis of ferrocene and acetylferrocene (on silica TLC plate) which prediction is correct: A) ferrocene is more pol

yaroslaw [1]

Answer:

Alternative C would be the correct choice.

Explanation:

The dual compounds were evaluated on something like a TLC plate through three separate additives in conducting a TLC study of ferrocene versus acetylferrocene.
The polar as well as nonpolar ferrocene where nonpolar is about 0.63 with the maximum $R_f$ value, and indeed the polar is somewhere around 0.19 with $R_f$ .
TLC plate (30:1 toluene/ethanol) established with.

The other three choices are not related to the given circumstances. So that option C would be the appropriate choice.

8 0

3 years ago

reddit The amount of NE released by sympathetic nerve terminals will be most strongly influenced by a change in which of the fol

erastovalidia [21]

Answer: Extracellular [Ca2+]

Explanation:

The sensitivity and density of the alpha receptors serve to enhance the response to the release of norepinephrine (NE) . However, they do not exert a strong influence as the concentration of calcium ions on the amount of norepinephrine (NE) released by sympathic nerve terminals.

The release of neurotransmitters depends more on either an external or internal stimulus.This results in an action potential which on reaching a nerve terminal, results in the opening of Ca²⁺ channels in the neuronal membrane. Because the extracellular concentration of Ca²⁺ is greater than the intracellular Ca²⁺ concentration, Ca²⁺ flows into the nerve terminal. This triggers a series of events that cause the vesicles containing norepinephrine (NE) to fuse with the plasma membrane and release norepinephrine (NE) into the synapse. The higher the action potential, the higher the Ca²⁺ flow into the terminals resulting in higher amount of norepinephrine (NE) into the synapse, and vice versa.

Catechol-O-methyltransferase (COMT) is one of several enzymes that degrade catecholamines such as dopamine, epinephrine, and norepinephrine. It serves a regulatory purpose to lower the concentration of norepinephrine upon its release from nerve terminals.

8 0

3 years ago