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3 years ago

how many ml of a 22.5% (v/v) ethanol solution would you need to measure out in order to have 12.5 ml of ethanol ?

1 answer:

8 0

Volume percent or volume/volume percent (v/v%) is used when preparing solutions of liquids. It will have units of volume of the smaller composition substance over the volume of the solution. We calculate as follows:

12.5 mL ethanol = .225 mL ethanol / 1 mL solution ( V )
V = 55.56 mL of the 22.5 % by volume ethanol solution is needed

Hope this answers the question.

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For her school Science Fair, Alyssa designs an experiment to learn more about erosion. Her experimental set up is shown below. W

shutvik [7]

Answer:

if I am going to answer I need the set up

Explanation:

please show the set up and I will answer the question

8 0

3 years ago

Hannah is investigating how all of Earths systems can affect each other at any given moment. What is one way the cryosphere can

snow_lady [41]

The cryosphere can affect the atmosphere by letting the Earth get to warm. The cryosphere protects the Earth from getting to warm.

4 0

3 years ago

Read 2 more answers

Cuando aumenta la temperatura dentro de un recipiente cerrado que contiene un gas este se expande/comprime por que las partícula

Evgesh-ka [11]

Answer:

expande

forman se alejan

Explanation:

Según las leyes de los gases ideales;

La ley de Charles establece que el volumen de una masa dada de gas ideal es directamente proporcional a su temperatura a la presión simultánea.

Esto significa que cuando se calienta una masa dada de gas ideal, el gas se expande y las moléculas de gas se alejan unas de otras de acuerdo con la ley de Charles.

7 0

3 years ago

what is the percent yield of titanium (II) oxide if 20.0 grams of titanium (II) sulfide is reacted with water? The actual yield

earnstyle [38]

Answer : The percent yield of titanium (II) oxide is, 142.5 % and the impurities could have caused the percent yield to be so high.

Explanation : Given,

Mass of titanium(II) sulfide = 20.0 g

Molar mass of titanium(II) sulfide = 79.9 g/mole

Molar mass of titanium(II) oxide = 63.9 g/mole

First we have to calculate the moles of titanium(II) sulfide.

$\text{ Moles of titanium(II) sulfide}=\frac{\text{ Mass of titanium(II) sulfide}}{\text{ Molar mass of titanium(II) sulfide}}=\frac{20.0g}{79.9g/mole}=0.2503moles$

Now we have to calculate the moles of titanium(II) oxide.

The balanced chemical reaction is,

$TiS+H_2O\rightarrow TiO+H_2S$

From the reaction, we conclude that

As, 1 mole of titanium(II) sulfide react to give 1 mole of titanium(II) oxide

So, 0.2503 mole of titanium(II) sulfide react to give 0.2503 mole of titanium(II) oxide

Now we have to calculate the mass of titanium(II) oxide.

$\text{ Mass of titanium(II) oxide}=\text{ Moles of titanium(II) oxide}\times \text{ Molar mass of titanium(II) oxide}$

$\text{ Mass of titanium(II) oxide}=(0.2503moles)\times (63.9g/mole)=15.99g$

To calculate the percentage yield of titanium (II) oxide, we use the equation:

$\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

Experimental yield of titanium (II) oxide = 22.8 g

Theoretical yield of titanium (II) oxide = 15.99 g

Putting values in above equation, we get:

$\%\text{ yield of titanium (II) oxide}=\frac{22.8g}{15.99g}\times 100\\\\\% \text{yield of titanium (II) oxide}=142.5\%$

Hence, the percent yield of titanium (II) oxide is, 142.5 %

If the percent yields is greater than 100% that means the product of the reaction contains impurities which cause its mass to be greater than it actually.

5 0

3 years ago

What type of reaction occur in cyclohexene

olga_2 [115]

Cyclohexene is a cyclic, six-membered hydrocarbon that contains one double bond. The types of reactions that can occur in cyclohexene would be those that are typical with alkenes generally.

The pi-bonded electrons in the double bond are nucleophilic. So, electrophilic addition reactions could occur with cyclohexene. For example,

cyclohexene + HBr → bromocyclohexane

cyclohexene + H2O/H+ → cyclohexanol

cyclohexene + Br2 → trans-1,2-dibromocyclohexane (racemic)

The latter is a common test for alkenes where one adds bromine to a sample to see if there is decolorization, which would indicate the presence of nucleophilic pi bonds. Bromine, which is dark reddish-brown, will become clear as it reacts with an alkene to form a colorless haloalkane.

Cyclohexene can also be converted to the fully saturated cyclohexane by hydrogenation: cyclohexene + H2/Pd → cyclohexane.

5 0

3 years ago