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3 years ago

An element is made up from ?

Chemistry

2 answers:

mafiozo [28]3 years ago

5 0

Answer:

An element is made up from Atoms

sertanlavr [38]3 years ago

4 0

Answer:

Atoms

Explanation:

Elements are the chemical combinations of two or more atoms of the same kind

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3. A student carries out the clay-catalyzed dehydration of cyclohexanol starting with 10 moles of cyclohexanol and obtains 500 m

IrinaK [193]

Answer:

$49.45~%$

Explanation:

In this case, we have to start with the chemical reaction:

$C_6H_1_2O~->~C_6H_1_0~+~H_2O$

So, if we start with 10 mol of cyclohexanol ( $C_6H_1_2O$ ) we will obtain 10 mol of cyclohexanol ( $C_6H_1_0$ ). So, we can calculate the grams of cyclohexanol if we calculate the molar mass:

$(6*12)+(10*1)=82~g/mol$

With this value we can calculate the grams:

$10~mol~C_6H_1_0\frac{82~g~C_6H_1_0}{1~mol~C_6H_1_0}=820~g~C_6H_1_0$

Now, we have as a product 500 mL of $C_6H_1_0$ . If we use the density value (0.811 g/mL). We can calculate the grams of product:

$500~mL\frac{0.811~g}{1~mL}=405.5~g$

Finally, with these values we can calculate the yield:

$%~=~\frac{405.5}{820}x100~=~49.45%$ %= (405.5/820)*100 = 49.45 %

See figure 1

I hope it helps!

6 0

3 years ago

The area surrounding the Pacific Ocean is often referred to as the ring of Firee due to the concentration of geologic events. De

viva [34]

Answer:

The amount of movement of tectonic plates in the area

Explanation:

The population density vary across the countries

Japan(127m), Philippines ( 103m), Indonesia (267m).

The volcanoes in Indonesia are among the most active of the pacific Ring of Fire along the north east island

5 0

3 years ago

A chemist adds 0.50L of a 0.485 M copper(II) sulfate CuSO4 solution to a reaction flask. Calculate the millimoles of copper(II)

den301095 [7]

Explanation:

It is given that volume is 0.50 L and molarity is 0.485 M. Hence, number of millimoles will be calculated as follows.

Number of millimoles = Molarity × Volume

As there are 1000 mL in 1 L. So, 0.50 L equals 500 mL.

Therefore, putting the given values into the above formula as follows.

Number of millimoles = Molarity × Volume

= 0.485 M × 500 mL

= 242.5

Thus, we can conclude that 242.5 millimoles of copper(II) sulfate has been added by the chemist to the flask.

4 0

3 years ago

The force of attraction between a divalent cation and a divalent anion is 1.64 x 10-8 N. If the ionic radius of the cation is 0.

Elden [556K]

The radius of the anion is 7.413 nm

<h3>How to calculate the force of attraction between charges</h3>

The force of attraction (F) is given by the formula:

F = (1/4π∈r²)(Zc*e)(Za*e)

where:

∈ = permittivity of free space = 8.85*10⁻¹⁵ F/m

Zc = charge on the cation = +2

Zc = charge on the anion = -2

e = charge on an electron = 1.602 * 10⁻¹⁹ C

r = interionic distance

r = rc + ra

where rc and ra are the radius of the cation and anion respectively

F = 1.64 * 10⁻⁸ N

Therefore based on the equation of force of attraction:

1.64 *10⁻⁸ = [1/4π(8.85*10⁻¹⁵)r²](2 * 1.602*10⁻¹⁹)²

r² = 5.63 * 10⁻¹⁷

r = 7.50 nm

Since r = rc + ra

where rc = 0.087 nm

thus, ra = r - rc = 7.50 - 0.087

ra = 7.413 nm

Therefore, the radius of the anion is 7.413 nm

Learn more about ionic radius at: brainly.com/question/2279609

6 0

2 years ago

How many particles are in chemicals

stepan [7]

Answer:

6.022 x 10^23 particles

Explanation:

Chemists have chosen to count atoms and molecules using a unit called the mole (mol), from the Latin moles, meaning “pile” or “heap.”

One mole is 6.022 x 10^23 of the microscopic particles which make up the substance in question.

Hope this helped! :^)

4 0

2 years ago