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Explanation:

The principle used in the preparation of these salts is to dissolve

the cystine in an alcoholic alkali solution to which just sufficient

water to effect solution has been added, and, after filtering from

excess cystine, to precipitate the salt by addition of a suitable

indifferent solvent. While various solvents, such as acetone,

ether, or large amounts of alcohol caused precipitations, these were

either oily or amorphous. Only acetonitrile was found to possess

the power of initiating regular crystallization in the salt solutions.

While the solutions of the different salts require different amounts

of the solvent for complete precipitation, a partial substitution of

absolute ether for acetonitrile was found expedient in the case

of the most soluble of the salts, the K salt.

Answer:

It is simply a process of forming crystal.

Explanation:            When salt is heated and dissolve in the liquid mainly water then its called saturated solution. When we further add salt and increase heat in order to dissolve it then it forcibly dissolve in liquid it's called supersaturated solution. After we slowly cool down the temperature then the salt we have put in supersaturated solution arises in the form of crystal. Hence its called crystalization.

Answer:

ionic compounds

Explanation:

just finished ap chem

Answer:

An ionic compound can act as an electrolyte. This is because an electrolyte should allow charges to travel inside it.

e.g = H2SO4, NaCl

Explanation:

Answer:

266 liters Carbon iv oxide will be formed

Explanation:

The first thing we need to do here is to calculate the number of moles of oxygen reacted.

This can be calculated using the ideal gas equation;

Mathematically;

PV = nRT

From the question;

P = pressure = 10.5 atm

V = volume = 400 liters

n = number of moles = ?

T = temperature = 125 + 273 = 398K

R = molar gas constant = 0.0821 L•atm•K^-1•mol^-1

Substituting these values, we have ;

n = PV/RT

n = (10.25 * 400)/(398 * 0.0821) = 125 moles

From the question;

15 moles oxygen gave 10 moles CO2

125 moles oxygen will give x moles CO2

x = (125 * 10)/15 = 83 moles

Now, we want to know the volume of CO2, present in 83 moles using the given reaction conditions.

Mathematically;

PV = nRT

V = nRT/P

= (83 * 0.0821 * 398)/10.25 = 265.65 which is approximately 266 Liters

Answer:

After the reaction, there will 0.60 g of magnesium oxide and 0.25 g of oxygen gas present in the tube

Explanation:

Equation of the reaction between magnesium and oxygen is given as follows:

2Mg(s) + O₂(g) ---> 2MgO(s)

From the equation of reaction, 2 moles of magnesium reacts with i mole of oxygen gas to produce 1 mole of magnesium oxide

molar mass of magnesium is 24.0 g; molar mass of oxygen gas = 32.0 g; molar mass of magnesium oxide = 40.0 g

Therefore 24 g of magnesium reacts with 32 g of oxygen gas

I.00 g of magnesium will react with (24.0 / 32.0) * 1.00 g of oxygen = 0.75 g of oxygen gas.

Therefore, magnesium is the limiting reagent. Once it is used up, the reaction will stop and the excess oxygen will be left in the tube together with the product, magnesium oxide.

mass of excess oxygen = 1.00 - 0.75 = 0.25 g

mass of magnesium oxide formed = (24.0 / 40.0 g) * 1 = 0.60 g

Answer:

The solubility of KNO₃ at 40° C is 1 mol/dm³

Explanation:

The solubility of a substance is the number of moles of that substance (solute)  contained in a unit volume of solvent at that particular temperature.

Now, Solubility = n/V where n = number of moles of KNO₃ and V = volume of saturated solution = 50.0 cm³ = 0.05 dm³

n = m/M where m = mass of KNO₃ = 5.05 g and M = molar mass of KNO₃ = 101 g/mol

n = 5.05 g/101 g/mol = 0.05 mol

Solubility = n/V

= 0.05 mol/0.05 dm³

= 1 mol/dm³

So, the solubility of KNO₃ at 40° C is 1 mol/dm³

Answer:

B) 82 protons

Explanation:

The number of protons for an element never change. 82 Is the atomic number for Pb which is how many protons it has. An isotope means it has more neutrons.

Answer:

The molecules move more slowly and their average kinetic energy decreases

Explanation:

The increased temperature meant that the atoms in liquid had a greater average energy of motion so as the temperature decreases the reaction would be inverse.

The branch of science which deals with the chemicals bond is called chemistry.

The correct option is B.

The energy which is produced by the motion of the particles is called kinetic energy. Temperature increases the motion of the particles. So, the kinetic energy increases when the temperature rises.

According to the question, the temperature of the water decreases therefore the kinetic energy decreases.

Hence, the correct option is B that is the molecules move more slowly and their average kinetic energy decreases.

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https://brainly.com/question/25026730

Explanation:

Deliquescent substances are solids that absorb moisture from the atmosphere until they dissolve in the absorbed water and form solutions. Efflorescent: Efflorescent substances are solids that can undergo spontaneous loss of water from hydrated salts.

Answer:

3.125g/mol

Explanation:

To find the molar mass of the gas, we need to initially find the number of moles (n) contained in the gas. To find the number of moles, we use the general gas law whose equation is:

PV=nRT

Where; P= Pressure

V= Volume occupied by gas

n= number of moles

R= general gas constant

(0.0821 L atm mol/K)

T= absolute temperature

According to the question; P= 2.0atm, V= 2.0L, n= ?, T= 298K

To find n, we make it the subject of the formula:

n= PV/RT

n= 2.0 × 2.0 / 0.0821 × 298

n= 4/ 24.4658

n= 0.16mol

If number of moles (n) of the gas is 0.16mol and it weighs 0.500g, its molar mass can be found using:

number of moles (n) = mass (g) / molar mass

Making MM subject of the formula;

molar mass = mass / number of moles

MM= 0.500/0.16

MM= 3.125

Hence, the molar mass of the gas is 3.125g/mol.

Answer:

neutrons :

Explanation:

Protons are positively charged, while electrons are negatively charged. Neutrons are electrically neutral, as the name suggests. The electric charge, noted Q , is a physical quantity.

Answer: A. 3 mol [tex]Cl_2[/tex] 3 mol Al:

Explanation:

Te given balanced chemical equation is :

[tex]2Al+3Cl_2\rightarrow 2AlCl_3[/tex]

According to the stochiometry :

A: 3 mol [tex]Cl_2[/tex] 3 mol Al:

3 moles of chlorine reacts with 2 moles of aluminium

B. 2 mol [tex]Al[/tex] 3 mol [tex]Cl_2[/tex]:

2 moles of aluminium  reacts with 3 moles of chlorine

C.  2 mol [tex]AlCl_3[/tex] 2 mol Al

2 mol of aluminium produces 2 mol of [tex]AlCl_3[/tex]

D. 3 mol [tex]Cl_2[/tex] 2 mol [tex]AlCl_3[/tex]

3 moles of chlorine produces with 2 moles of [tex]AlCl_3[/tex]

Thus the conversion factor not used for mole to mole calculations is  3 mol [tex]Cl_2[/tex] 3 mol Al:

Answer:

venus

Explanation:

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-Zylynn

Answer: I would say that Saturn is most like Earth. Not only does it have moons, like Earth, but the atmosphere is also denser like Earth. It also has windstorms, granite they are much more intense than Earth’s, but they do indeed happen. Saturn also has hydrogen gas; this gas is here on Earth supporting life in our ocean. Therefore, there is a chance that the conditions on Saturn could provide the essentials for there to be life.

Answer:

Partial pressure of H₂ = 0.9556 atm

Explanation:

Given:

Barometric pressure = 753 torr

Vapor pressure of water = 26.74 torr

FInd:

Partial pressure of H₂

Computation:

Partial pressure of H₂ = Barometric pressure - Vapor pressure of water

Partial pressure of H₂ = 733 - 26.74  

Partial pressure of H₂ = 726.26 torr

1 atm = 760 torr

So,

Partial pressure of H₂ = 726.26/760

Partial pressure of H₂ = 0.9556 atm

Answer:

–1

Explanation:

The electronic configuration of the neutral atom is given below:

2 8 7

From the electronic configuration of the neutral atom, we can see that the atom has 7 electrons in it's outermost shell. This implies that the element needs 1 more electron to complete it's octet configuration.

Therefore the charge on the ion of the element will be –1 indicating that the atom has received 1 electron to complete it's octet configuration.

Answer:

0.333333 cal/g-°C

Explanation:

Energy = mass x specific heat capacity x temperature change.

(E = mcΔT)

Energy = 100.0 cal

specific heat capacity c= unknown

mass m = 4.0 g

temperature change ΔT = 100 - 25 =75°

100 = 4c(75)

c = 0.333333 cal/g-°C

Answer:

The metre is defined as the length of the path travelled by light in a vacuum in 1/299 792 458 of a second.

Answer:

Initial volume of the container (V1) = 1.27 L (Approx)

Explanation:

Given:

Number of mol (n1) = 5.67 x 10⁻²

Number of mol (n2) = (5.67 +2.95) x 10⁻² = 8.62 x 10⁻²

New volume (V2) = 1.93 L

Find:

Initial volume of the container (V1)

Computation:

Using Avogadro's law

V1 / n1 = V2 / n2

V1 / 5.67 x 10⁻² = 1.93 / 8.62 x 10⁻²

V1 = 10.9431 / 8.62

Initial volume of the container (V1) = 1.2695

Initial volume of the container (V1) = 1.27 L (Approx)

Answer: 1.27 L

Explanation:

First, calculate the final number of moles of propane (n2) in the container.

n2 = n1 + nadded = 5.67 × 10^−2 mol + 2.95 × 10^−2 mol = 8.62 × 10^−2 mol

Rearrange Avogadro's law to solve for V1.

V1 = V2 × n1 / n2

Substitute the known values of n1, n2, and V2,

V1 = 1.93 L × 5.67 × 10^−2 mol / 8.62 × 10^−2 mol = 1.27 L

Answer:

b) 1s22s22p63s23p5

Explanation:

Answer:

b) 1s22s22p63s23p5

Explanation:

edge 2021

Answer:

because water gas has high heat content more than producer gas

Explanation:

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Answer: 0.938 moles of [tex]ZnCl_2[/tex] will be produced.

Explanation:

To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]

moles of zinc:

[tex]\text{Number of moles}=\frac{61.0g}{65g/mol}=0.938moles[/tex]

[tex]Zn+2HCl\rightarrow ZnCl_2+H_2[/tex]

As HCl  is in excess , zinc is the limiting reagent and it limits the formation of product.

According to stoichiometry :

1 mole of Zn produce =  1 mole of [tex]ZnCl_2[/tex]

Thus moles of  Zn produce = [tex]\frac{1}{1}\times 0.938=0.938[/tex] moles of [tex]ZnCl_2[/tex]

Thus 0.938 moles of [tex]ZnCl_2[/tex] will be produced.

Answer:

Niels Bohr, refined the model of an atom by proposing a quantized shell structure atomic model in order to describe how the electrons are able to maintain stable orbits around the nucleus

Based on the predictions of classical mechanics the electron motion of the Rutherford model was unstable as the electrons where expected to have lost some energy during motion and thus having to come rest in the nucleus

According to the modification by Neils Bohr in 1913, electrons move in  shells or orbits of fixed energy and emission of electromagnetic radiation takes place only when electrons changes the orbit in which they move

Explanation:

Answer:

The amount of isopropyl alcohol contained in 150 ml of the solution is 117.15 grams

Explanation:

The density of a substance is the mass per unit volume, therefore, we have;

The density of the isopropyl alcohol = 0.785 g/ml at 25°C

The  density = mass/volume

Mass = Density × Volume

The mass of the 150 ml of isopropyl alcohol is therefore;

Mass = 0.785 g/ml × 150 ml = 117.15 g

The amount in grams contained in 150 ml of sample = 117.15 g.

Answer:

Basic

Explanation:

The pH scale is a scale that tells us about the concentration of hydrogen ions in a solution.

Acids have many hydrogen ions. Acids have a pH of less than 7.

Bases have fewer hydrogen ions and more hydroxide ions.  Bases have a pH of less than 14.

If the solution has a pH of exactly 7, then it is pure water. Water has the same concentration of hydrogen and hydroxide ions.

The antacid tablet has a pH of roughly 9.5 Since this is less than 14, but not equal to or less than 7, this must be an base. Therefore, it is considered to be in the basic range.

Answer:

9.5 is a base

Explanation:

A ph of less than 7 is an acid

7 is neutral

7 to 14 is a base

9.5 is a base

Answer:

10.2 L of CO₂

Explanation:

Our reaction is:

2C + O₂  →  2CO₂

We convert the mass of C, to moles:

5.50 g / 12g/mol = 0.458 moles

Ratio is 2:2, so if 2 moles of C can produce 2 moles of CO₂ then 0.458 moles of C would produce 0.458 moles of gas.

By the Ideal Gases Law, we know that 1 mol of gas is contained in 22.4L, so:

0.458 mol . 22.4L / 1mol = 10.2 L

Answer:

A solute is a solid which dissolves in a solvent. Muddy water contains water and soil, soil does not dissolve in water

Answer:

A meteorologist studies meteorology which is the study of the atmosphere in order to predict/forecast the weather.

Explanation:

I hope this helps.

Answer:

they study the atmosphere and atmospheric events of our weather

Explanation:

Answer:

B)  40 individuals emigrate, 0 individuals die, 10 individuals are born, 28 individuals immigrate

Explanation:

its right on edg2020 :)

Answer:

110 feet each second......

I think

Answer:

110 hope its right

Explanation: