I. Determine the mass of reactants and products that will be needed if one mole of P4(s) reacts completely, as follows

P4(s) + 6 H2(g) →4 PH3(g)

II. What is the total mass of the reactants? What is the mass of the products?

III. What principle is illustrated by this example?

If someone could really help me with explanation as well thank you very much

Answer:

Volume percent of a solution that has 10.0 g of ethanol= 12.37%

Volume percent of a solution that has 90.0 g of water = 87.69%

Explanation:

Volume Percent:

The volume percent helps us  to indicate the concentration of the solution when the volume of the solute and volume of the solution is given by

[tex]Volume Percent=\frac{\text{Volume of the Solute}}{\text{Volume of Solution}}\times100%[/tex]

With respect to density 1mL of ethanol

=> 0.7893g or 10g of methanol contains

=> [tex]\frac{1}{0.7893}\times10[/tex]

=> 12.67mL

And for water = [tex]\frac{1}{0.9987} \times 90.0[/tex]

=> 90.12mL

Now total volume = 90.12+ 12.67 = 102.79mL

%(v/v) for water = [tex]\frac{90.12}{102.79}\times 100[/tex]

 = 87.69%

%(v/v) for ethanol = [tex]\frac{12.67}{102.79}\times 100[/tex]

 = 12.37%

The volume percent of ethanol in the solution is 12.3%, and the volume percent of water is 87.7%. This is calculated by determining the volume of each substance using their respective densities and the mass provided and then finding the percentage of each substance's volume in the total solution volume.

To find the volume percent of a solution that has 10.0 g of ethanol with a density (D) of 0.7893 g/mL, and 90.0 g of water with a density (D) of 0.9987 g/mL, we first calculate the volumes of each component. For ethanol, divide 10.0 g by 0.7893 g/mL to get the volume in milliliters. For water, divide 90.0 g by 0.9987 g/mL to get the volume in milliliters.

To calculate the volume of ethanol: 10.0 g / 0.7893 g/mL = 12.7 mL
To calculate the volume of water: 90.0 g / 0.9987 g/mL = 90.2 mL
Assuming volumes are additive: Total volume of the solution = 12.7 mL (ethanol) + 90.2 mL (water) = 102.9 mL

Now, we can find the volume percent of ethanol: (volume of ethanol / total volume of solution) × 100% = (12.7 mL / 102.9 mL) × 100% = 12.3%

The volume percent of water is similarly calculated: (volume of water / total volume of solution) × 100% = (90.2 mL / 102.9 mL) × 100% = 87.7%

https://brainly.com/question/15461083

#SPJ3

Answer:

250000000000 ml of apple juice

When solid sodium hydroxide (NaOH) dissolves in water, it dissociates into Na+ and OH- ions. The OH- ions react with water to produce more hydroxide ions and hydrogen ions, resulting in a basic solution.

The net ionic equation for the dissolution of solid sodium hydroxide, NaOH (s), in water involves the dissociation of NaOH into its constituent ions:

2NaOH (s) → 2Na+ (aq) + 2OH- (aq)

The OH- ions contribute to the basicity of the solution by reacting with water to produce hydroxide ions (OH-) and hydrogen ions (H+):

OH- (aq) + H2O (l) → OH- (aq) + H2O (l)

https://brainly.com/question/35907805

#SPJ6

Final answer:

Sodium hydroxide (NaOH) forms a basic solution when dissolved in water by dissociating completely into sodium (Na+) and hydroxide (OH−) ions, with the hydroxide ions responsible for increasing the solution's basicity.

Explanation:

The question relates to how solid sodium hydroxide (NaOH) forms a basic solution when dissolved in water. To illustrate this, we use the net ionic equation, which highlights the dissociation process of NaOH into ions in an aqueous solution. The equation is as follows:

NaOH(s) → Na+ (aq) + OH− (aq)

This equation shows that solid sodium hydroxide dissociates completely into sodium ions and hydroxide ions upon being dissolved in water. The presence of hydroxide ions (OH−) is crucial because they increase the hydroxide ion concentration in the solution, making it basic. Sodium hydroxide is a strong base, and this complete dissociation is characteristic of strong bases, further emphasizing the significance of the hydroxide ions in rendering the solution basic.

Dalton's principles that atoms are the smallest units, identical atoms form an element, and atoms can combine to form compounds remain valid. The principles that atoms have specific weights and can't be divided, created, or destroyed have been updated.

Most of Dalton's five principles from his atomic theory still hold true in general. However, some have been tweaked or expanded with new understanding. The principles that still remain valid include: atoms are the smallest units that matter can be broken into (although we now know about subatomic particles); all atoms of a specific element are identical; and atoms of different elements can combine in specific ratios to form compounds. atomic weights of elements may differ, and atoms cannot be divided, created or destroyed have been updated with modern atomic theory which includes the existence of isotopes, nuclear reactions that can transmutate elements and subatomic particles that makeup atoms respectively.

https://brainly.com/question/31935526

#SPJ6

Dalton's atomic theory, with its revolutionary principles, still largely holds true today in the realm of chemistry. His claims about the conservation of matter during chemical change and that elements cannot be broken into simpler substances are valid. However, his ideas about isotopes had to be revised to account for their variations in mass.

John Dalton, an English schoolteacher, revolutionized chemistry with his atomic theory, changing the way we understand the composition of matter. Despite two thousand years of the Aristotelian view dominating, Dalton drastically reshaped our conception with his principles.

Most of Dalton's principles still hold true today: atoms cannot be destroyed or created during a chemical change, allowing the total mass of matter to remain constant (the law of conservation of matter). This argues that substances like copper, which consist of one type of atom, cannot be broken down to simpler substances composed of fewer types of atoms.

However, some of his postulates, notably those surrounding isotopes, had to be modified. Originally Dalton thought that all atoms of the same element had the same mass and properties. This notion was altered in the wake of isotopes - variations of elements with different masses - to clarify that atoms of the same element must have identical chemical properties.

https://brainly.com/question/11855975

#SPJ6

If there were an element above fluorine, its state would be a gas. This is because fluorine is located in the non-metal section of the periodic table which can all be found as a gas at room temperature.

Answer:

activation activation energy is defined as the minimum amount of energy needed to start a reaction.

Answer:

Stored Energy(☞ﾟヮﾟ)☞☜(ﾟヮﾟ☜)¯\_(ツ)_/¯

Explanation:

To find the pressure of CH4 gas in a flask, one must convert the mass of methane to moles, plug it into the Ideal Gas Law equation (PV = nRT), and solve for pressure. After calculation, the pressure of the methane gas at 25°C in a 1.75 L flask is approximately 0.33 atm.

To calculate the pressure of CH4 gas in a flask using the Ideal Gas Law, you need to use the amount of substance (in moles), the volume of the container, the temperature, and the ideal gas constant in appropriate units. First, convert the mass of CH4 to moles by dividing by the molar mass of methane (16.04 g/mol). Then, use the Ideal Gas Law formula PV = nRT to solve for pressure (P).

Moles of CH4 = 0.357 g / 16.04 g/mol = 0.02226 mol

Given: V = 1.75 L, T = 25°C (which is 298.15 K when converted to Kelvin), R = 0.08206 L atm/mol K

Now, substitute the values into the Ideal Gas Law equation:

P = (nRT) / V

P = (0.02226 mol * 0.08206 L atm/mol K * 298.15 K) / 1.75 L

P = 0.3298 atm

Therefore, the pressure of CH4 gas in the flask at 25°C is approximately 0.33 atm.

Answer:

speed of plane in still air  =  252 mph

speed of wind  = 42 mph.

Explanation:

Given:

Distance travelled by the small plane = 245  

Time taken to fly 245 miles =  1 hour and 10 minutes.

Time taken for return trip = 50 minutes.

To Find:

speed of the wind=?

The speed of the plane in still air=?​

Solution:

We Know that

[tex]speed = \frac{distance}{time}[/tex]  

=>[tex]\frac{245}{ \frac{70}{60}} hours[/tex]

=>[tex]\frac{245}{ \frac{7}{6}} hours[/tex]

=>[tex]245 \times { \frac{6}{7}[/tex]

=>210  mph against wind

on way back

=>[tex]\frac{245}{ \frac{50}{60}} hours[/tex]

=>[tex]\frac{245}{ \frac{5}{6}} hours[/tex]

=>[tex]245 \times { \frac{6}{5}[/tex]

=> 294

Now

294 = plane +wind------------------------(1)

210 =plane - wind-------------------------(2)

Solving (1) and (2)

2 plane = 504

plane = 252

plane = [tex]\frac{504}{2}[/tex]

So  substituting plane value in eq(2) we get,

210 =252 - wind

wind = 42 mph

The speed of the wind is 35.6 miles per hour in the opposite direction of the plane's movement, and the speed of the plane in still air is 209.4 miles per hour.

To solve this problem, we can use the formula:

Plane speed in still air = (total distance) / (total time)

Given that the plane flew 245 miles in 1 hour and 10 minutes against the wind, and the return trip took 50 minutes, we can calculate the speed of the wind and the speed of the plane in still air as follows:

Step 1: Convert the time to hours:
1 hour and 10 minutes = 1.17 hours
50 minutes = 0.83 hours

Step 2: Calculate the speed of the plane in still air using the formula:
Speed of the plane in still air = (total distance) / (total time)
Speed of the plane in still air = 245 / 1.17 = 209.4 miles per hour

Step 3: Calculate the speed of the wind by finding the difference between the speed of the plane in still air and the actual speed of the plane against the wind:
Speed of the wind = Speed of the plane in still air - Speed of the plane against the wind
Speed of the wind = 209.4 - 245 = -35.6 miles per hour

Therefore, the speed of the wind is 35.6 miles per hour in the opposite direction of the plane's movement, and the speed of the plane in still air is 209.4 miles per hour.

https://brainly.com/question/34356766

#SPJ11

Answer:

B) is reduced.

Explanation:

Oxidation:

Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.

Reduction:

Reduction involve the gain of electron and oxidation number is decreased.

Consider the following reactions.

4KI + 2CuCl₂  →   2CuI  + I₂  + 4KCl

the oxidation state of copper is changed from +2 to +1 so copper get reduced and it is oxidizing agent.

CO + H₂O   →  CO₂ + H₂

the oxidation state of carbon is +2 on reactant  side and on product side it becomes  +4 so carbon get oxidized and it is reducing gent.

Oxidizing agents:

Oxidizing agents oxidize the other elements and itself gets reduced.

Reducing agents:

Reducing agents reduced the other element are it self gets oxidized.

Answer:

[tex]\boxed{\text{0.17 mol}}[/tex]

Explanation:

[tex]\text{M$_{r}$ of Na} = 22.99\\\text{Moles} = \text{3.9 g } \times \dfrac{\text{1 mol}}{\text{22.99 g}} = \text{0.17 mol}\\\\\text{ The sample contains $\boxed{\textbf{0.17 mol}}$ of Na}[/tex]

Answer: They ionize by the gain of one electron

Explanation:

Group 7 elements have seven electrons on their outermost shell, in order to have a complete octet structure, the go into bonding with other elements by gaining one more electron to have eight complete outermost shell electron (valence electron). They thereby ionize by gain one electron forming X[tex]X^{-1}[/tex]

Answer:

As Bob add more solute to dissolves, the rate of solution will be decreases

Explanation:

At certain temperature the maximum amount of solute dissolve in the specific amount of solution or solvent.

There are many factors that affect solubility of the solute in solvent. Nature of the solute also affects the rate of solubility.

Temperature also affects the rate of solubility. Solubility increase when the temperature increases.

Pressure: Change in pressure have no effect on the rate of solubility

The rate of solution:  is a measure that how fast a substance dissolves in solvent.

Amount of solute already dissolved affect the rate of solution. If a solvent have little amount of solute in the solution it dissolve quickly. But when you have more solute in the solution the process was slower.

1 g of lead dissolves in 100 g of water at room temperature.  Similarly 5 mg of sodium hydroxide pellet dissolve in 100ml of water at room temperature.

So if Bob add 1 mg more of NaOH in the same 100ml of water the rate of the solubility decreases.

As there are some factors that decrease the solubility rate of NaOH pellet as follow:

• large size of the solute dissolve slowly as the solubility process take on      the surface of the solute particles, powders dissolve fast.

• less amount of solvent with ratio to solute

• saturated solution

So due to all above reasons the rate of the solubility decreases upon adding a little more amount of NaOH pellet.

Answer:

a

Explanation:

:)

Answer: Increase in the average kinetic energy.

Explanation: They are proportional so if one increases the other increases.

Final answer:

Temperature reflects the average kinetic energy of particles in an object; an increase in temperature results in an increase in this energy, leading to faster movement of particles, greater entropy, and potentially faster chemical reactions.

Explanation:

Kinetic Energy and Temperature Relationship

Temperature is a measure of how hot or cold an object is and is directly proportional to the average kinetic energy of the particles within that object. An increase in temperature leads to an increase in the average kinetic energy, which is observable as more extensive vibrations in solids, more rapid translations in liquids and gases, and a larger distribution of kinetic energies among the particles. This results in more frequent particle collisions and an increase in entropy, due to the more dispersed distribution of kinetic energies at high temperatures.

In the context of chemical reactions, the increase in temperature and kinetic energy tends to create a faster reaction rate, as particles move more quickly and are more likely to come into contact to react. It is critical to understand that no chemical reaction or phase change is considered in this explanation. The focus is strictly on the relation between thermal energy, temperature, and kinetic energy.

Answer:

Concentration = 0.14 M

Explanation:

Given data:

Volume of base = 19.62 mL

Molarity of base = 0.341 M

Volume of acid = 25.00 mL

Molarity of acids = ?

Solution:

Number of moles of base = Molarity × volume in litter

Number of moles = 0.341 mol/L × 0.02 L

Number of moles =  0.007 mol

Concentration of acid:

Concentration = 1/2 (0.007 mol) / 25 mL × 10⁻³ L/mL

Concentration = 0.0035 mol / 25 × 10⁻³ L

Concentration = 1.4  × 10⁻¹ M

Concentration = 0.14 M

Answer:

70g

Explanation:

Rate = 35g of NaCl can dissolve in 100g of H2O

Use proportions for 200g of H2O:

[tex]\frac{35}{100} = \frac{x}{200}[/tex]

Since 200 is double of 100, x needs to be double of 35.

[tex]\frac{35}{100} = \frac{70}{200}[/tex]

Therefore the maximum amount of NaCl that can dissolve in 200g of water is 70g.

Answer:

a = The chemical equation written by balancing the total number of atoms of each element in reactants and products is called balanced chemical equation.

Answer:

a b d

these are part of an ecosystem or can be

Answer:

Mass = 1.76 g

Explanation:

Given data:

Volume of solution = 25 mL

Molarity = 0.45 M

Amount of CuSO₄.5H₂O = ?

Solution:

Molarity = number of moles / volume in litter

Number of moles = Molarity × Volume in L

Number of moles = 0.45 M  × 0.025 L

Number of moles = 0.011 mol

Mass of f CuSO₄.5H₂O:

Mass = Number of moles ×  molar mass

Mass = 0.011 mol × 159.6 g/mol

Mass = 1.76 g

Answer:

selenium dioxide

Explanation:

The Lewis dot structure for SeO shows a double bond between Selenium (Se) and oxygen (O), with each atom sharing two of its six valence electrons to form the double bond and retaining the remaining as non-bonding pairs.

The Lewis dot structure for SeO (Selenium monoxide) consists of selenium represented by the symbol 'Se', surrounded by six valence electrons drawn as dots, and oxygen represented by 'O', surrounded by six valence electrons. Selenium and oxygen form a double bond which is illustrated by sharing four of their electrons (two pairs), while the remaining electrons are the non-bonding pairs.

The structure can be drawn as follows: Se = O :

In this diagram, ':' represents the non-bonding pairs of valence electrons while '=' represents the electron pairs making up the double bond between selenium and oxygen.

https://brainly.com/question/11554350

#SPJ6

Answer:

Option D

Explanation:

In Sulphur dioxide molecule both sulphur and oxygen have 6 valence electrons

The oxidation state of Sulphur in Sulphur dioxide molecule is +4 and the oxidation state of oxygen in Sulphur dioxide molecule is -2

Both sulphur and oxygen in this molecule are non-metals and therefore there will be no ionic bond present between them

So bond formation in this molecule takes through sharing of electrons between sulphur and oxygen and due to the sharing of electrons, covalent bond formation takes place between them

As there are only covalent bonds involved, this molecule is a covalent molecule

∴ Sulphur dioxide molecule is covalent and formed by the sharing of electrons

Final answer:

Sulfur and oxygen, both in group 16, have six valence electrons. Sulfur dioxide (SO2) is formed by the sharing of electrons, creating a covalent bond with a sulfur oxidation state of 4+.

Explanation:

From their location on the periodic table, both sulfur and oxygen are in group 16 and have six valence electrons. The typical oxidation state for oxygen is 2-, and sulfur can also have an oxidation state of 2-. However, sulfur is known to exhibit a range of oxidation states, including positive ones in certain compounds.

Regarding reactivity, oxygen is highly reactive and forms oxides with most elements. Sulfur also reacts with many elements, including metals, forming sulfides, and multiple oxidation states when reacting with nonmetals. The reaction between sulfur and oxygen results in the formation of sulfur dioxide, SO2, which is a compound where sulfur has a 4+ oxidation state.

The correct statement that most accurately describes the compound formed by sulfur and oxygen is D) Sulfur dioxide, SO2, is covalent, formed by the sharing of electrons.

Answer:

Ionic compounds are electrically neutral because the positive ions and the negative ions in the compound cancel each other.

Explanation:

Ion- It is an atom or a molecule that has an equal number of protons (subatomic particles with positive electric charge) and electrons (subatomic particles with negative electric charge).

Positive ion- This is also called a "cation." It consists of more protons than electrons.

Negative ion- This is also called an "anion." It consists of more electrons than protons.

Ionic compounds are electrically neutral because they consist of anions and cations. This neutralizes the compounds. A common example of ionic compound is the NaCl (Sodium Chloride). The Na (Sodium) atom loses an electron in order to become Na+ while the Cl (Chlorine) atom gains an electron in order to become Cl-. This interaction balances them together.  

Ionic compounds are electrically neutral overall because the total number of positive charges of the cations equals the total number of negative charges of the anions. This allows ionic compounds to maintain overall neutrality despite the presence of positive and negative ions.

In every ionic compound, the total number of positive charges of the cations equals the total number of negative charges of the anions. Thus, ionic compounds are electrically neutral overall, even though they contain positive and negative ions. We can use this observation to help us write the formula of an ionic compound. The formula of an ionic compound must have a ratio of ions such that the numbers of positive and negative charges are equal.

Answer:

[tex]\large \boxed{\text{7.94 g/mol}}[/tex]

Explanation:

We can use the Ideal Gas Law to solve this problem

pV = nRT

Data:

p = 0.998 atm

V = 0.153 L

T = 26 °C

m = 0.0494 g

1.  Convert temperature to kelvins

T = (26 + 273.15) K =  299.15 K

2. Calculate the number of moles

[tex]\text{0.998 atm} \times\text{0.153 L} = n \times \text{0.082 06 L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1}\times \text{299.15 K}\\\\0.1527 = n \times \text{24.55 mol}^{-1}\\\\n = \dfrac{0.1527}{\text{24.55 mol}^{-1}} = 6.220 \times 10^{-3} \text{ mol}[/tex]

3. Calculate the molar mass

[tex]\text{Molar mass} = \dfrac{\text{mass}}{\text{moles}}\\\\M = \dfrac{m}{n}\\\\M = \dfrac{\text{0.0494 g}}{6.220 \times 10^{-3} \text{ mol}}\\\\M = \textbf{7.94 g/mol}\\\text{The molar mass of the gas is } \large \boxed{\textbf{7.94 g/mol}}[/tex]

Answer:

a. chromium (III) chloride

Explanation:

Chromium chloride is also binary ionic compound composed of only two element chromium and chlorine.

When naming these compounds the name of metal or cation is written first and anion is written after the cation. The anions are non meals.

The anion name is end with suffix " ide".

such as chromium chloride.

The (III) shows the oxidation number of metal. In given compound the oxidation state of chromium is +3 while chlorine chow the oxidation state of -1 that's why three chlorine atoms are attached with one chromium atom.

Final answer:

The ionic compound CrCl3 is correctly named chromium(III) chloride, identifying the trivalent state of chromium in the compound.

Explanation:

The correct name for the ionic compound with the formula CrCl3 is chromium(III) chloride. This name indicates that the chromium ion in the compound has a valency of three, which is communicated by the Roman numeral III. Ionic compounds such as this are named by stating the metal ion followed by the non-metal ion with an -ide ending, and when the metal can form ions with different charges, the specific charge is included in parentheses in Roman numerals immediately after the name of the metal.

Some similar examples include iron(II) chloride (FeCl2) and iron(III) chloride (FeCl3), where the Roman numerals II and III denote the valency of the iron ion in each compound, respectively.

Answer:

12.04 × 10²³ atoms

Explanation:

Given data:

Mass of cobalt = 117.86 g

Number of atoms = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

For example,

Number of moles of cobalt = 117.86 g/ 58.9 g/mol

Number of moles of cobalt = 2 mol

one moles of cobalt =  6.022 × 10²³ atoms of cobalt

2 moles × 6.022 × 10²³ atoms / 1 mol

12.04 × 10²³ atoms

Answer:

71 grams of chlorine gas.

Explanation:

2Na + Cl2 = 2NaCl.

From the molar masses:

2(23+35.45) g of NaCl are made from  2*35.45 g Cl2 gas.

So  117 g are made from  (2*35.45  * 117)  / 2(23+35.45)

= 71 g.

To make 117 grams of sodium chloride, you would need 121 grams of chlorine gas.

To calculate the amount of chlorine gas needed to make 117 grams of sodium chloride, we need to use stoichiometry.

Step 1: Convert the mass of sodium chloride to moles using the molar mass of NaCl which is 58.4 g/mol.

Step 2: Use the balanced equation to determine the mole ratio between chlorine gas and sodium chloride. From the equation 2Na + Cl2 -> 2NaCl, we can see that 1 mole of Cl2 reacts with 2 moles of NaCl.

Step 3: Convert moles of Cl2 to grams using the molar mass of Cl2 which is 70.9 g/mol.

Therefore, to make 117 grams of sodium chloride, we need (117 g NaCl) * (1 mol NaCl / 58.4 g NaCl) * (1 mol Cl2 / 2 mol NaCl) * (70.9 g Cl2 / 1 mol Cl2) = 121 grams of chlorine gas.

https://brainly.com/question/30218216

#SPJ3

Answer:

combination reaction

Explanation:

In a combination reaction two reactants combine to form a single product, like in  this case.

Other options are incorrect because:

The reaction 2Fe + 3Cl2 → 2FeCl3 is an example of a combination reaction, where two or more simple substances combine to form a single product.

The chemical reaction provided, 2Fe + 3Cl2 → 2FeCl3, is an example of a combination reaction. In this type of reaction, two or more reactants (in this case, Fe and Cl2) combine to form a single product (FeCl3). The reactants are usually elements or simple compounds, and the product is a compound made up of all the atoms from the reactants.

Unlike a combustion reaction, which involves burning in oxygen, or a single-replacement reaction, where one element replaces another in a compound, this combination reaction involves simple substances joining together.

https://brainly.com/question/37930038

#SPJ11

0.4266 moles of C₂H₆O

Explanation:

The problems asks for the number of moles in 25 mL of C₂H₆O with a density of 0.785 g/mL.

First we calculate the mass of C₂H₆O:

density = mass / volume

mass of C₂H₆O = density × volume

mass of C₂H₆O = 0.785 × 25

mass of C₂H₆O = 19.625 g

Now we calculate the number of moles of C₂H₆O:

number of moles =  mass / molecular weight

number of moles of C₂H₆O = 19.625 / 46

number of moles of C₂H₆O = 0.4266 moles

Learn more about:

number of moles

https://brainly.com/question/14015076

#learnwithBrainly

The number of moles in a 25.0 mL sample of C2H6O with a density of 0.785 g/mL is approximately 0.426 moles.

To calculate the number of moles of C2H6O in a 25.0 mL sample given its density, you would first calculate the mass of the liquid using the formula: mass = density × volume. With a density of 0.785 g/mL, the mass of C2H6O in 25.0 mL would be 25.0 mL × 0.785 g/mL = 19.625 grams. The molar mass of C2H6O (which is ethanol or dimethyl ether, depending on the structural arrangement, but the question likely refers to ethanol) is approximately 46.07 g/mol. Therefore, the number of moles is calculated as:

mass / molar mass = 19.625 g / 46.07 g/mol = approximately 0.426 moles.

This calculation yields the number of moles present in the given volume of the substance.

1.88 g

We are given;

We are required to determine the amount of uranium left after 2 days

N = N₀ × 0.5^n

Where, N is the remaining mass, N₀ is the original mass and n is the number of half lives.

n = (2 × 24) ÷ 12 hours

  = 4

Therefore;

Remaining mass, N = 30.0 g × 0.5^4

                                = 1.875 g

                                = 1.88 g

Therefore, the mass of the remaining sample after decay is 1.88 g

The reaction that can extract silver metal from a silver nitrate solution is Equation 1, where zinc metal reacts with silver nitrate, displacing the silver and allowing it to precipitate.

To extract silver metal from silver nitrate solution, one would look for a chemical reaction where a more reactive metal displaces silver from its compound. In Equation 1, we have AgNO3 reacting with Zn, which is a more reactive metal known to displace other metals in a single displacement reaction. The reaction between zinc and silver nitrate can be represented as follows: Zn(s) + 2AgNO3(aq)
ightarrow Zn(NO3)2(aq) + 2Ag(s). This results in the precipitation of silver metal (Ag). References to similar reactions such as the reaction between copper and silver nitrate, where silver is also displaced and precipitated, support this concept.

On the other hand, Equation 2, which involves MgCl2 reacting with AgNO3, does not lead to a displacement reaction to extract silver because chlorides are usually spectators in such reactions unless conditions like oxidation or other complex reactions are involved. Additionally, MgCl2 itself as a compound does not have a free metal to displace silver from silver nitrate.

Therefore, the reaction that can be used to extract silver metal from a silver nitrate solution is Equation 1, where zinc metal is reacting with silver nitrate.

Answer:

option D is correct that is  8.2 g

Explanation:

Data Given:

mole of NaCl = 0.14 mol

Volume of water = 1 L

Weight of Nacl = ?

Solution:

In this we know the amount of NaCl and to find weight of NaCl to form a solution.

So,

Formula Used

    no. of moles = weight in g / Molar mass . . . . . . . . . . (1)

Molar mass of NaCl = 23 + 35.5

Molar mass of NaCl = 58.5 g/mol

Rearrange equation (1)

        no. of moles = weight in g / Molar mass . . . . . . . . . . (1)

        weight of Nacl =  no. of moles x Molar mass . . . . . . . . . . (2)

Put values in the Equation 2

             weight of Nacl = 0.14 mol x 58.5 g/mol

              weight of Nacl = 8.2 g

weight of Nacl = 8.2 g

So option D is correct that is  8.2 g