Q4. When 20 g of salt is added to a beaker containing 100 g of water, the salt dissolves and seems to disappear as a solution is formed. A) What is the mass now? B) Explain your answer.​

Answers

Answer 1
A. 120g
B. This is because the salt forms a solution with the water hence their individual masses will be summer giving you a mass greater than both individual masses.
Answer 2

The mass of the solution is equal to 120 g. As the salt dissolves in water so it disappears when the solution is formed.

Why does salt dissolve in water?

The salt dissolves in water at the molecular level, due to electrical charges. Due to this fact that both water and salt are polar, with positive and negative charges on opposite sides of their molecule. The bonds in salt are ionic and have an electrical charge.

Likewise, a water molecule is also ionic in nature, but the covalent bonds are present with two hydrogen atoms and one oxygen atom, which has a negative charge. The salt dissolves because the covalent bonds of water molecules are stronger than the ionic bonds present in the salt molecules.

The mass of the given salt is equal to 20 g while the mass of water is 100g. The total mass of the solution is equal to the sum of the mass of the solute and the mass of the solvent. Therefore, the mass of the solution will be equal to 120 grams whether the salt gets dissolved in water and get disappeared.

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Related Questions

using the equation 40kj+ 2so3= 2so2+02, of so3=0.491, so2=0.17, 02=0.701, find Keq

Answers

The equilibrium constant, Keq for the reaction, given the data from the question is 0.084

What is equilibrium constant?

The equilibrium constant, Keq for a reaction is the ratio of the concentration of the products raised to their coefficients to the ratio of the concentration of the reactants raised to their coefficients. For example, the equilibrium constant for the reaction nA + mB <=> eC can be obtained as follow

Keq = [C]^e / [A]^n × [B]^m

How to determine the equilibrium constant for the reaction Equation: 40 KJ + 2SO₃ <=> 2SO₂ + O₂[SO₃] = 0.491 M[SO₂] = 0.17 M[O₂] = 0.701 MEquilibrium constant (Keq) =?

The equilibrium constant, Keq for the above reaction can be obtained as illustrated below:

Keq = [SO₂]^2 × [O₂] / [SO₃]^2

Keq = (0.17)^2 × (0.701) / (0.491)^2

Keq = 0.084

Thus, the equilibrium constant, Keq for the reaction is 0.084

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Describe how water contributes to the fitness of the environment to support life.

Answers

Water contributes to the fitness of the environment to support life by acting as a Solvent for molecules to interact Moderate Earth's climate.

Water contributes to the fitness of the environment to support life in several ways :

Life on Earth began in water and evolved there for 3 billion years before colonizing the land.Even terrestrial organisms are tied to water.Most cells are surrounded by water.Cells are about 70–95% water.Water is a reactant in many of the chemical reactions of life.Water is the only common substance that exists in the natural world in all three physical states of matter: solid ice, liquid water, and water vapour.Water stabilizes air temperatures by absorbing heat from warmer air and releasing heat to cooler air.Water can absorb or release relatively large amounts of heat with only a slight change in its own temperature.Water’s high heat of vaporization moderates climate.Much of the sun’s heat absorbed by tropical oceans is used for evaporation of surface water.Water is unusual because it is less dense as a solid than as a cold liquid.Most materials contract as they solidify, but water expands.At temperatures above 4°C, water behaves like other liquids, expanding as it warms and contracting as it cools.Water begins to freeze when its molecules are no longer moving vigorously enough to break their hydrogen bonds.When water reaches 0°C, water becomes locked into a crystalline lattice, with each water molecule bonded to a maximum of four partners.

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Compared to a solution with a ph value of 7, a solution with a thousand times greater hydronium ion concentration has a ph value of.

Answers

Answer:

pH of  4

Explanation:

Upon comparing a solution with a pH value of 4 and that having a pH of 7, you will realize that it has a pH difference of 3 although the concentration of ions of hydrogen having a pH of 7 is 1000 times greater than being at a pH of 4.

A student sets up the following equation to convert a measurement.
(The ? stands for a number the student is going to calculate.)
Fill in the missing part of this equation.
Note: your answer should be in the form of one or more fractions multiplied together.

Answers

Answer:

[tex]\frac{1,000 g}{1 kg}[/tex]  ·  [tex]\frac{100 cm}{1 m}[/tex]

Explanation:

The final answer has a different set of units. In particular, kilograms (kg) changes to grams (g) and meters (m) changes to centimeters (cm). To make this change, you need to multiply the first value by proportions.

When writing these proportions, it is important that they are arranged in a way that allows for the cancellation of units. For instance, since both kg and m are located in the numerator, they must be located in the denominators of the conversions.

Proportions:

1 kg = 1,000 g

1 m = 100 cm

The full expression:

[tex]-4.3*10^4 \frac{kg*m}{s}[/tex]  ·  [tex]\frac{1,000 g}{1 kg}[/tex]  ·  [tex]\frac{100 cm}{1 m}[/tex]  =  [tex]?\frac{g*cm}{s}[/tex]                     ^        ^

As you can see, the old units cancel out and you are left with g and cm in the numerator.

What type of reaction is a grignard reaction? What is the critical intermediate (which can be isolated and enables the final product)?

Answers

Organometallic Chemical reaction is a Grignard reaction. The critical intermediate (which can be isolated and enables the final product) is the formation of a carbon bond.

The Grignard Reaction is an organometallic chemical reaction that mostly produces C-C bonds. When organic molecules are combined with the Grignard reagent, the Grignard reaction occurs (Rmgx).

The Grignard Reaction is the conversion of an aldehyde or ketone into secondary or tertiary alcohol by the addition of an organomagnesium halide (Grignard reagent). A primary alcohol is produced when formaldehyde and oxygen react.

Alcohol and water molecules have acidic hydrogen atoms that Grignard reagents quickly react with. A proton substitutes the halogen in a Grignard reaction with water, producing an alkane as the end result. Therefore, the Grignard reagent offers a two-step process for changing a haloalkane into an alkane.

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The element lithium (Li) has 3 protons and 3 electrons. The element fluorine (F) has 9 protons and 9 electrons. An atom of the element lithium (Li) transfers an electron to an atom of the element fluorine (F). Which type of bond results between the atoms, and what happens to the charges in each of the atoms?

Answers

When an atom of the element lithium (Li) transfers an electron to an atom of the element fluorine (F), then the bond results between the atoms is ionic bond.

what is chemical bond?

A chemical bond is defined as the bond which holds atoms together in molecules.

Bonds arise due to the electrostatic forces present between positively charged atomic nuclei and negatively charged electrons.

Types of chemical bondIonic bondCovalent bondCoordinate bond

What is Ionic bond ?

Ionic bond is defined as the transfer of electron from one atom to another atom.

Since, electron transfer from lithium to fluroine. Thus lithium get positive charge and fluorine occupy negative charge.

Thus, the bond form between lithium atom and fluorine atom is ionic bond.

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Carbon dioxide released by automobiles is an example of a(n) ________ source of pollution. volatile point multi-point non-point aerosol.

Answers

Carbon dioxide released by automobiles is an example of a(n) non-point source of pollution.

Nonpoint source pollution is typically caused by hydrologic alteration, drainage, seepage, precipitation, especially land runoff. Contrary to pollution from industries and sewage treatment facilities, nonpoint source (NPS) pollution originates from a variety of diffuse sources.

Point-source pollution can be defined as pollution coming from a single, distinguishable source, such as a factory and sewage plant output pipe. Nonpoint-source pollution would be pollution that doesn't come from a single source or point.

Therefore, Carbon dioxide released by automobiles is an example of a(n) non-point source of pollution.

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Find the percent ionization of a 0. 337 m hf solution. The ka for hf is 3. 5 × 10^-4.

Answers

Percent ionization = 3.17%

We utilize the supplied acid equilibrium constant (Ka) to calculate the percentage of the acid that is ionized. It is the ratio of the acid and dissociated ion equilibrium concentrations. The HF acid would dissociate in the manner described below:

HF = H+ + F-

The following is how the acid equilibrium constant might be written:

Ka = [H+][F-] / [HF] = 3.5 x 10-4

We utilize the ICE table to determine the equilibrium concentrations.

        HF             H+              F-

I      0.337           0                 0

C      -x              +x               +x

---------------------------------------------

E    0.337-x        x                   x

3.5 x 10-4 = [H+][F-] / [HF]

3.5 x 10-4 = [x][x] / [0.337-x]

Solving for x,

x = 0.01069 = [H+] = [F-]

percent ionization = 0.01069 / 0.337 x 100  = 3.17%

percent ionization = 3.17%

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Which are properties of all metals (except hg)? i. good conductors of heat and electricity ii. easily formed into sheets or wires iii. chemically unre

Answers

The properties of all metals are "good conductors of heat and electricity".

Metals are excellent heat or electricity conductors and were malleable, ductile materials that may be pulled into wire and pounded into sheets. Apart from mercury, which appears a liquid at ambient temperature, most metals have solids with a distinctive silvery shine.

Due to the metals' atoms' ability to create a matrix across which outside electrons could easily travel, metals make good electrical and thermal conductors. The positive nuclei of the connecting metal ions are surrounded by a sea of electrons rather than orbiting their individual atoms.

Therefore, the properties of all metals are "good conductors of heat and electricity".

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The density of lithium is 0. 546 g/cm3. what volume is occupied by 3. 66 x 10 23 atoms of lithium?

Answers

The volume occupied by 3.66 x [tex]10^{23}[/tex] atoms of lithium is 7.73 [tex]cm^3[/tex]

What is Density?

The density of a substance is defined as the mass of the substance per unit volume. It is often denoted by the symbol ρ

The density of a substance is given by,

[tex]\rho = \frac{m}{V}[/tex]

The mass of a substance is the measure of the amount of matter present in it. It is generally measured in grams (g) or kilograms (kg).

The volume of a substance is defined as the amount of 3D space occupied by it.

What is Mole Concept?

It is a concept which uses mole as a unit to measure the number of atoms, molecules or ions.

A mole is defined as the amount of substance which has the same number of elementary particles as there are atoms in 12 grams of [tex]\ce{^{12}C}[/tex]

1 mole = Avogadro's number = 6.022 x [tex]10^{23\\[/tex] atoms

Steps to find out the volume

Molar Mass of Lithium = 6.94 g/mol

1 mole of Lithium has 6.022 x [tex]10^{23}[/tex] atoms

3.66 x [tex]10^{23}[/tex] atoms of lithium has molar mass = [tex]\frac{6.94 g}{6.022\times10^{23} } \times 3.66 \times 10^{23}[/tex]

[tex]m = 4.218 g[/tex]

Substitute in density formula,

[tex]\rho = \frac{m}{V}[/tex]

[tex]V = \frac{m}{\rho}[/tex]

[tex]=\frac{4.218g}{0.546g/cm^3}[/tex]

= 7.73 [tex]cm^3\\[/tex]

Therefore, 3.66 x [tex]10^{23}[/tex] atoms of lithium occupies 7.73 [tex]cm^3\\[/tex] of volume.

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Which reaction is an oxidation reaction?
a. 1-octene → octane
b. octane → 1-octene
c. 1-octanal → 1-octanol
d. 1,3-octadiene → 1-octene
e. 1-chlorooctane → 1-octanol

Answers

1-octanal → 1-octanol is an oxidation reaction.

Oxidation

The removal of hydrogen or any other electropositive element, or the addition of oxygen, is said to be the process of oxidation in classical or earlier concepts. The process of an atom or ion losing one or more electrons is known as oxidation, according to the electronic notion.

An oxidizing agent is something that causes oxidation. O2, S, Cl2, Br2, and H2O2 are oxidizing agents in the instances above. Oxidation has an easy source. When an atom, molecule, or even an ion comes into contact with oxygen, oxidation results. When this occurs, it changes to achieve a more stable structure in its electron shells and transfers electrons as a result.

Any chemical process, including oxidation, is primarily brought on by atoms attempting to obtain valence shells with a complete complement of electrons. The stability of the species is increased by this optimum configuration.

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The reaction between an alcohol and an anomeric carbon of a carbohydrate forms a _____ bond.

Answers

glycosidic is the answer

What does the kinetic theory state about the relationship between the speed and temperature of gas molecules?

Answers

As the temperature increases, the speed of gas molecules increases

The kinetic theory state about the relationship between the speed and temperature of gas molecules as with an increase in temperature, the speed of gas molecules increases.

The energy that an object possesses as a result of its motion is known as kinetic energy.

The average of the kinetic energies of all the particles in a system is known as the average kinetic energy.

The following equation provides the answer:

K = [tex]\frac{3RT}{2}[/tex]

K= kinetic energy

R= gas constant

T= temperature

It is clear from above that kinetic energy and system temperature are inversely correlated. Therefore, if the temperature is higher, the system's average kinetic energy will also be higher, increasing the speed of the molecules.

What does kinetic theory state?

The kinetic theory of matter states that all matter is made of small particles that are in random motion and that have space between them.

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A particular buffer solution consists of a weak acid and its conjugate base. How could this buffer solution be modified so as to increase its buffer capacity against added base?

Answers

The only way increase the buffer capacity is to increase the total concentration of the system (conjugated acid + base).

What is buffer capacity?

The buffer capacity can be defined as the amount of strong base needed to change the pH of 1 liter of solution by 1 pH unit.

To increase buffer capacity to modify buffer solution-

The buffer capacity of a buffer, consisting of a weak acid and its conjugated base is given by the following equation:

π=㏑ 10 [{H⁺} + K ÷ H⁺ + CKα [H⁺]  ÷ [H⁺]  + Kα]

With [H^+] the concentration of the H^+ ion ; C the total buffer concentration (i.e. acid + conjugated base) and the acidity constant.

It is clear from this equation that the buffer capacity is directly proportional to the concentration.

So the only way increase the buffer capacity is to increase the total concentration of the system (conjugated acid + base).

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If the concentration of red dye #40 in the original syrup is 4. 68 x 10-3 m, what is its concentration in dilution #3?.

Answers

Concentration difficulties can be caused by medical, cognitive, or psychological problems or may be related to sleep disorders or medications, Psychological conditions

What is Concentration?Concentration means focused attention, and it has many uses and benefits. It assists in studying, enables faster comprehension, improves memory, helps in focusing on a task, job, or goal, and enables you to ignore meaningless and irrelevant thoughts.Taking very small breaks by refocusing your attention elsewhere can dramatically improve mental concentration after that. The next time you are working on a project, take a break when you begin to feel stuck. Move around, talk to someone, or even switch to a different type of task.Concentration difficulties can be caused by medical, cognitive, or psychological problems or may be related to sleep disorders or medications, Psychological conditions that can interfere with concentration include anxiety, depression, bipolar disorder, emotional trauma, and stress.

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How would you distinguish benzoic acid and benzyl alcohol by their infrared spectra?

Answers

The OH peaks in the IR spectra of benzyl alcohol and benzoic acid should be compared and contrasted.

What is the IR spectra of Benzoic acid?The right-hand portion of the infrared spectrum of benzoic acid, between wavenumbers 1500 and 400 cm-1, is referred to as the fingerprint region. It results from a special combination of intricately overlapping vibrations of the atoms within the benzoic acid molecule.What is the IR spectra of Benzyl alcohol?A C-Cl bond is frequently shown by a peak at 700.There are a few more peaks at 1500 that are directed at a C=C bond.What is IR spectra?

The percent transmittance (or absorbance) of the radiation through the molecule against the radiation's wave number forms the IR spectrum.

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It is important to contrast and compare the OH peaks in the IR spectra of benzyl alcohol and benzoic acid.

What does benzoic acid's IR spectrum look like?The fingerprint region is the region between wavenumbers 1500 and 400 cm-1 on the right side of the infrared spectrum of benzoic acid.The benzoic acid molecule's atoms vibrate in a unique pattern that involves intricately overlapping vibrations, which causes it.

What does benzyl alcohol's IR spectrum look like?A peak at 700 is typically used to indicate a C-Cl bond.At 1500, there are a couple more peaks that are focused on a C=C bond.

How do IR spectra work?The IR spectrum is made up of the radiation's wave number divided by its percent transmittance (or absorbance) through molecules.

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Hi I need help and I am willing to give brainliest
Can you help me find the percent yield of SiO2 given the equation of SiCl4 + O2 → SiO2 + Cl2

the starting amount for SiCl4 is 150g and O2 at 200g. the actual yield for SiO2 is 49.2 g.
Thank you for any help

Answers

1. The first step is to convert your given masses into moles. This way, you can see which reactant is in excess and which one is limiting. A good flow of thought would be: kilograms of SiO2/Carbon→ grams SiO2/Carbon→moles SiO2/Carbon.

2. Repeat this step for the carbon reactant.

3. By comparison, we can tell that the carbon reactant is in excess, which means that the SiO2 reactant is limiting. Because of this, we’ll use the amount of SiO2 to find our percent yield. There’s only so much SiO2 that can react with the carbon.

4. You can now calculate the actual and theoretical yields. The theoretical yield is larger than the actual yield because it does not have physical interactions like loss of energy to the environment and friction to interfere with the reaction.

5. Now compare your two values of actual and theoretical. The formula for percent mass is [(Actual yield)/(Theoretical yield)]*100%. Our final answer for this question is the percent yield of the reaction is 90.8% We can interpret this as 90.8% of the SiO2 reacting will produce solid silicon.

Hope this helps!!

According to the iupac convention for chemical naming, which part of a hydrocarbon is selected as the main chain for a hydrocarbon chain?

Answers

Answer:

The longest continuous chain

Explanation:

A piece of plastic has a net charge of 2. 00 μc. How many more protons than electrons does this piece of plastic have?

Answers

The piece of plastic has   1.256× 10¹³  protons  more than  that of electrons.

What are protons and electrons?

A proton is a subatomic particle with a defined mass of 1 and a charge of +1 (positive charge). The symbol for the proton is either p or p+.

An electron is a subatomic particle that has a negative electric charge and that actively orbits the nucleus of the atom .

To calculate ,

given ,

magnitude of charge , q=+2μC=+2×10⁻⁶

Since, protons carry positive charge. Then, we know that standard number of proton in 1 Coulomb of charge is,

1C=6.28×10¹⁸ protons

Number of protons in 1 microcoulomb charge is,

=6.28×10¹⁸×10⁻⁶

=6.28×10¹²

Then for the net charge of q, the number of protons is given as,

np= q×6.28×10¹²

np= 2×6.28×10¹²

np=1.256×10¹³ protons

Thus, the piece of plastic has 1.256×10¹³   more protons than electrons.

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The half-life of sr-90 is 28 years. after 56 years of decay only 0. 40 g of a sample remains. what was the mass of the original sample?
a. 0. 050 g
b. 0. 10 g
c. 3. 2 g
d. 1. 6 g

Answers

Half-life is the time taken for the concentration of the substance to reduce by 50%. The original sample of strontium had a mass of 1.6 gms. Thus, option d is correct.

What is half-life?

The half-life of any radioactive substance is the time period at which the concentration will get reduced to half the initial amount. The initial mass of Sr-90 is calculated as,

[tex]N(t) = N_{0} (\dfrac{1}{2})^{ \frac{t }{t 1/2}}[/tex]

Given,

Quantity of the remaining substance N (t) = 0.40 gm

Initial radioactive substance quantity [tex]N_{0}[/tex] =?

Time duration (t) = 56 years

Half-life = 28 years

Substituting values above:

[tex]\begin{aligned} 0.40 &= N_{0} (\dfrac{1}{2}) ^{{\frac{56}{28}}\\\\0.40 &= N_{0} (\dfrac{1}{2})^{2}\end{aligned}[/tex]

= 1.6 gm

Therefore, option d. the initial mass of Sr is 1.6 gm.

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You are asked to weigh approximately 0. 4g of acetylsalicylic acid to the nearest mg. When you enter the data in grams in your lab notebook, how many significant figures will you record ?.

Answers

The significant figures will be 1.

As, weight of acetylsalicylic acid = 0. 4 g

We obtain 400 mg when we convert 0.4g of acetylsalicylic acid to mg.

So, 400 milligrams are worth 0.4 grams when converted to grams.

There is just one significant figure because 0 before a decimal is not significant i.e. 4.

What are significant figures?

The digits of a number that have relevance in relation to the measurement's resolution are known as significant figures. Additionally known as significant figures in chemistry. All experimental measurements are subject to some degree of uncertainity.

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The ph of a 0. 50 m solution of base b is found to be 10. 19. what is the kb of the base? the equation described by the kb value is b(aq) h2o(l)↽−−⇀bh (aq) oh−(aq)

Answers

The pH of a 0.50 M solution of base B is found to be 10.19. The Kb of the base is 4.8 × 10⁻⁸.

Let's consider the following basic reaction.

B(aq) + H2O(l) ⇄ BH(aq) + OH⁻(aq)

First, we will calculate the pOH of the solution using the following expression. (14-10.19)=3.81

antilog -3.81=1.55×10^-4/0.50=4.8×10^-8

The pH of a 0.50 M solution of base B is found to be 10.19. The Kb of the base is 4.8 × 10⁻⁸.

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The [tex]K_b[/tex] of the base b is 4.805 × 10⁻⁸.

What is dissociation constant?

The dissociation constant is a type of equilibrium constant that measures the degree of dissociation of a salt.

[tex]K_a[/tex] is the dissociation constant for the acid which describes the strength of an acid.

[tex]K_b[/tex] is the dissociation constant of the base which describes the strength of a base.

pOH = 14 - pH = 14 - 10.19 = 3.81

pOH = -log[OH⁻]

3.81 = -log[OH⁻]

Antilog (-3.81) = [OH⁻]

[OH⁻] = 1.55 × 10⁻⁴

Here,

[tex]K_b= \frac{[BH^+][OH^-]}{[B]}[/tex]

     = [tex]\frac{(1.55\times10^{-4})(1.55\times10^{-4})}{0.50}[/tex]

     = 4.805 × 10⁻⁸

The Kb of the base b is 4.805 × 10⁻⁸

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Why are thiols more nucleophilic than alcohols?

Answers

Answer:

Thiols contain stronger acids than alcohols

Explanation:

Answer:

Sulfur is a bigger atom than oxygen and has a lower electgronegativity value. Therefore, the lone pair availability in thiol is higher than alcohol

Explanation:


What would the corresponding
concentration values of H₂O be
for pH values: 1, 3, 5, 7, 9, 11?

Answers

Answer:

7,9,11

Explanation:

this is because water includes 0H, which would mean that it is more than 6

Semiconductors are more effective than metals as converters of solar radiation into electricity because?

Answers

Semiconductors show the property of both the conductor and insulator. They are more effective than metals as their valence electron can free flow by the sun's energy. Thus, option B is correct.

What are semiconductors?

Semiconductors are substances and materials that exhibit intermediate properties of conductors and insulators. They are solid materials that can conduct electrical charges due to the added impurity or change in temperature.

They have a valence electron in their outer shell that can absorb the energy from the sun to get excited. This leads to the flow of the charge in the semiconducting substance more easily.

Therefore, option B. the semiconductors can absorb the extra energy is correct.

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Your question is incomplete, but most probably your full question was, Semiconductors are more effective than metals as converters of solar radiation into electricity because

A. it is easier for the atoms of a semiconductor to absorb solar energy and to move from place to place within the solid, thereby conducting electricity.

B. the energy contained in sunlight gives the valence electrons in the semiconductor atoms the extra energy they need to "flow" throughout the solid.

C. metals melt much too easily under direct sunlight and, as liquids, lose their ability to conduct electricity.

D. solar radiation has sufficient energy to knock electrons completely off the metal surface, making it impossible for the electrons to "flow" from atom to atom and conduct electricity.

calculate the pressure exerted by an book of mass 20kg occupying an area of 2 m square.​

Answers

The answer is 100 Pa.

The formula for calculating pressure is :

Pressure = Force ÷ Area

We are given that :

mass = 20 kgarea = 2 m²

We also know that :

Force = mass ×g

So, force will be :

F = 20 × 10 F = 200 N

Now, we can finally calculate pressure :

P = 200 ÷ 2P = 100 Pa

What is the molarity of a solution in which 55. 49 g of calcium chloride is dissolved in enough water to make 500. ml of solution?

Answers

The molarity of a solution in which 55. 49 g of calcium chloride is dissolved in enough water to make 500. ml of solution is 1M.

What is molarity?

It is defined as number of moles of solute divided by volume of solution.

Given,

Mass of CaCl2 =55.49g

Molar mass of CaCl2 =40+35+35=110g

Mole= given mass/ molar mass

= 55.49/110=0.50mol.

Now, putting all values we get the molarity

Molarity =0.5×1000/500=1M

Thus, the molarity of given solution is 1M.

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When an allergen binds with ige antibodies on mast cells, resulting in release of chemical mediators, this reaction is called:_________

Answers

When an allergen binds with IgE antibodies on mast cells, resulting in release of chemical mediators, this reaction is called Type I reactions.

The Type I reactions is also known as immediate hypersensitivity reaction.

This reaction involve immunoglobulin E ( IgE ) - mediated release of histamine and other mediators from mast cells and basophils .

Examples : anaphylaxis and allergic rhinoconjunctivitis.

The IgE molecules bind to high - affinity receptors on the surface of mast cells and basophils and the subsequently cross-linking of these molecules with the allergen releases performed and newly synthesized mediators.

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A mixture of h2po4- and oh- is allowed to react. what are the products of the reaction?

Answers

When mixture of H2PO4- and OH- is allowed to react. The products of the reaction are as follow

H2PO4+ OH--------HPO4(2-)+H2O

In the reaction above H2PO4(2-) is donating the proton to OH Resulting in H2O and the deprotonated species. This makes it a bronsted lowry acid.

According to Bronsted lowry, acid are those which donate proton.

In the given problem, H2PO4- is bronsted lowry acid. So it donate electron to OH- to form water.

Thus, the product formed in the given reaction is water and H2PO4(2-).

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A pharmaceutical company wants to test the efficiency of its new drug production techniques so they run 3 shifts of production for 4 hours each and collect the product at the end of each shift. Their chemical engineers predict a maximum of 7000 grams of product can be created each shift. Shift one produces 4562 grams. Shift two produces 5783 grams. Shift three produces 5247 grams. What is the average percent yield for this new production technique?

Answers

The percentage yield of the  new production technique is 82.8%

What is the percentage yield?

Production is the procedure by which finished products are obtained form the raw materials. The production process involves the passing of raw materials through a certain procedure that involves the use of certain machines and equipment to give us the required products.

We are told in the question that there are three shifts;

Shift 1 produces 4562 grams

Shift 2 produces 5783 grams

Shift 3 produces 5247 grams

Average production from the three shifts = 4562 grams + 5783 grams +  5247 grams/3 = 5197 grams

The theoretical average yield is =  7000 grams + 7000 grams + 7000 grams/3 = 7000 grams

Now the percentage yield = actual yield/ theoretical yield * 100/1

percentage yield = 5197 grams/7000 grams * 100/1

percentage yield = 82.8%

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