Can someone do these? Brainliest included

Answer:

D. To ensure the cooling process is not affected by surrounding temperature

Explanation:

The conical flask acts as a temperature jacket.

The conical flask is used in freezing point of the naphthalene activity because to ensure the cooling process is not affected by surrounding temperature.

In the freezing point determination of naphthalene, a conical flask is used to hold the naphthalene sample and a thermometer. The conical shape of the flask allows for efficient stirring of the naphthalene as it is heated and cooled, ensuring that the temperature is evenly distributed throughout the sample.

The conical flask is also used to protect the naphthalene sample from any external temperature fluctuations that could affect the cooling process. By placing the flask in an ice bath, the cooling process can be closely monitored and controlled, allowing for accurate determination of the freezing point.

Therefore, the primary reason why a conical flask is used in the freezing point determination of naphthalene is to ensure that the cooling process is not affected by surrounding temperature.

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Answer:

I think it is C

Explanation:

Hope this helps!! :)

If I'm wrong, then greatest apologies

Answer:

I don't know yr language

Explanation:

Given the amount of fluorine is ---- 1.25 mol.

What is the mass of given fluorine in grams?

Since

[tex]Number of moles =\frac{given mass of the substance}{its molecular mass}[/tex]

To get the mass of the substance in grams, multiply the given number of moles with the molecular mass of the substance.

Hence, among the given options, the correct answer is the last option that is

Multiply the atomic mass of fluorine by 1.25.

Answer:

Multiply the atomic mass of fluorine by 1.25.

Explanation:

i got it right on the exam!! :)

Explanation:

number of moles=mass/molecular mass

molecular mass of calcium hydroxide=74

n=m/mr

=48.6/74

=0.65g/mol

I hope it helps

The number of moles of calcium hydroxide in a 48.6 g is 0.65 mol

The mole, symbol mol, is the SI base unit of amount of substance.

The quantity amount of substance is a measure of how many elementary entities of a given substance are in an object or sample.

Formula used :

Number of moles = mass / molecular mass

Molecular mass of calcium hydroxide = 74

n = m / mm

= 48.6 / 74

= 0.65 mol

Therefore, The number of moles of calcium hydroxide in a 48.6 g is 0.65 mol

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nobody can say it is uncertain but in my opinion it will grow quickly in the next 10 years

Respuesta:

4.26 M; 12.8 N

Explicación:

Primer paso: Calcular la concentración volumétrica (Cv)

Usaremos la siguiente expression.

Cv = Cg × ρ

Cv = 30 g%g × 1.39 g/mL = 41.7 g%mL

Segundo paso: Calcular la molaridad

La concentración volumetrica es 41.7 g%mL, es decir, hay 41.7 gramos de soluto cada 100 mL de solución. Usaremos la siguiente fórmula para molaridad.

M = masa de soluto / masa molar de soluto × litros de solución

M = 41.7 g / 97.99 g/mol × 0.1 L = 4.26 M

Tercer paso: Calcular la normalidad

Usaremos la siguiente fórmula.

N = M × Z

donde Z para un ácido es igual al número de protones.

N = M × Z

N = 4.26 mol/L × 3 eq/mol = 12.8 N

Answer:

it talks about reality ..how animals and human came to existence and how they disappear ..this is evolution

the environment chooses those who best fit in it and others are selected ..as in die ..this is referred to as natural selection

and further in this theory .animals produce off springs who survive in the environment

Answer:

two atoms

Explanation:

Answer:

TIMED HELP ASAP

19.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the dissolution of MgSO₄. (The specific heat of water is 4.184 J/g･°C and the density of the water is 1.00 g/mL). You can assume that the specific heat of the solution is the same as that of water.

Answer:

-21.03 kJ/mol

Explanation:

∆H is enthalpy. Enthalpy is the total heat content of a system.

So we can establish that ∆H = q (heat)

The formula for heat (q)

q = cm∆T

c = specific heat capacity

m = mass of substance

∆T= change of temperature

Since we are calculating the enthalpy of the SOLUTION. We must account for both the mass of water and the mass of MgSO₄ in our q formula.

All you gotta do is plug and chug at this stage.

∆H = q     = cm∆T = (4.184)(19.11+100.0)(6.70) = 3338.986808 Joules

We have now calculated the heat (aka enthalpy) of the solution.

BUT

Remember! The problem asked for enthalpy in kj....

Use this conversion factor.

1000 J = 1 kJ

3338.986808 Joules * 1kJ/1000 J = 3.338986808 kJ

We were asked to find ∆H for the dissolution of MgSO4  in units of kj/mol so we are not finished.

Take the grams of MgSO4 in the problem  and convert it into moles using its molar mass.

MgSO4 molar mass = 120.3676 g

1 mol = 120.3676 g MgSO4   <---- Use this as a conversion factor

19.11 g MgSO4 * 1 mol MgSO4/120.3676 g = 0.15876365 mol MgSO4

Now that you've calculated the moles of MgSO4 in this solution. You can divide your heat by it.

q dissolution = 3.338.986808 kJ/ 0.15876365 mol =  21.03 kj/mol

Note that the problem tells us that the temperature of water increases.

This means that the water is experiencing an endothermic process (heat is being absorbed from MgSO4) . Mathematically, this would be indicated by a positive sign. ---> +q

We can assume MgSO4 is losing heat as it is placed into the water. It is experiencing an exothermic process (heat is being lost).  Mathematically, this would be indicated by a negative sign. ----> -q

So if we're calculating the enthalpy for the dissolution of MgSO₄ ....the value we've arrived at must be negative.

Answer

∆H = 21.03 kj/mol :)))))

I hope that helped...I feel like my explanation was a bit convoluted.

Answer:

0.06 liter

Explanation:

First, let us look at the equation of the first reaction:

2HCl + Mg ----> MgCl2 + H2

2 moles of HCl requires 1 mole of Mg for complete reaction.

Mole of HCl available = molarity x volume

                                    0.2 x 50/1000 = 0.1 mole

Mole of Mg available = mass/molar mass

                                    0.6/24.3 = 0.02 mole.

Thus, HCl is in excess by 0.1 mole.

Now, let us look at the second reaction:

HCl + NaOH ----> NaCl + H2O

mole ratio of HCl to NaOH is 1:1

Remember that 0.1 mole HCl is left from the first reaction. Thus, 0.1 mole of the alkaline would also be needed.

Hence, volume of NaOH needed = mole/molarity

                        0.1/1.67 = 0.06 dm3

The volume of alkaline needed would, therefore, be 0.06 liter.

Answer:

C

Explanation:

∂S represents change in entropy.

Answer:

False

Explanation:

sea floor spreading is not consistent at all mid ocean ridges.

Answer:

Al2O3 + 6HCl ==> 2AlCl3 + 3H2O ... balanced equation

moles Al2O3 present = 30.0 g x 1 mol/101.96 g = 0.294 moles

moles HCl present = 30 g HCl x 1 mol/36.5 g = 0.822 moles HCl

HCl is LIMITING as it takes 6 moles HCl for each 1 mol Al2O3 and here that is not enough. It will run out first.

Now, using the limiting reactant, we find the moles and mass of AlCl3 that can be formed.

0.822 moles HCl x 2 moles AlCl3/6 moles HCl = 0.274 moles AlCl3 formed

mass of AlCl3 = 0.274 moles AlCl3 x 133 g/mole = 36.4 g AlCl3 formed

Answer:

a. H2O: dihydrogen monoxide

b. PCl5: Phosphorus pentachloride

c. SiF4: Silicon tetrafluoride

d. N20: dinitrogen oxide

The statement describes conditions in which a mineral can form is "Crystals of minerals dissolve in the groundwater in caves."

Atoms of the relatively similar element and atoms of other elements [such as silica (Si) and calcium (Ca)] can make up a crystal, and they are arranged in a predictable, repeating pattern.

A mineral would be an element as well as a chemical compound which has been produced as a result of geological activity and is often crystalline in nature.

The statement describes conditions in which a mineral can form as "Crystals of minerals dissolve in the groundwater in caves."

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Answer:

transition state is a point in which electrons been removed from the atom

Answer:

The highest energy structure in the reaction coordinate.

Explanation:

Answer:

Answer to the following question is as follows;

Explanation:

Alkynes' vapour pressure and normal boiling points are altered when chain length grows, since vapour pressure rises while boiling point falls.

Vapour pressure always include pressure entered by vapour with its condensed phase, pressure include molecules force of attraction include vapour

Answer:

174.259 g/mol

Explanation:

The molecular weight of potassium (K2so4) is 174.259 g/mol .

Hope it is helpful to you

Answer:

C. KMnO4/H+

Explanation:

Oxidizing agent is a substance that has the ability to accept electrons from other substances.

Answer:

oh it's easy

Explanation:

Take the hydrate

N

a

2

S

2

O

3

∙

5

H

2

O

. Are there ionic forces between the

N

a

+

and the

S

2

O

2

−

3

and ion-dipole forces between the cation/anions and the water?

Answer:

87059.50558 pa

Explanation:

Dalton's law of partial pressure states that Ptotal=P1 +P2+ P3

417mmHg + 150mmHg +86mmHg =653 mmHg

convert it to Pa, your answer is 87059.50558Pa.

I hope I'm of help to you

Answer:

No and Yes

Explanation:

it depends bc its an ionic compound, therefore can't conduct electricity when SOLID, BUT unless it DISSOLVES in water it can conduct