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A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

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A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

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Under adolf hitler, the nazis developed a carefully planned network of concentration camps. these were designed to hold all those deemed undesirable by the nazi leadership. an individual consigned to a camp was forced to work, given a specific uniform that was the same as all other prisoners, given a limited ration of food, no access to amenities, and faced a near certain death by poison gas. this tragic episode in human history is an extreme example of

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Under adolf hitler, the nazis developed a carefully planned network of concentration camps. these were designed to hold all those deemed undesirable by the nazi leadership. an individual consigned to a camp was forced to work, given a specific uniform that was the same as all other prisoners, given a limited ration of food, no access to amenities, and faced a near certain death by poison gas. this tragic episode in human history is an extreme example of

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What is the concentration of Sr2+ in a saturated solution of SrSO4? SrSO4 has a Ksp of 3.2 x 10–7

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What is the concentration of Sr2+ in a saturated solution of SrSO4? SrSO4 has a Ksp of 3.2 x 10–7

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Ccording to Le Chatelier’s principle, what happens when the concentration of a product is reduced in a chemical reaction that was in equilibrium? A. The equilibrium shifts to the right to favor the formation of products. B. The equilibrium shifts to the left to favor the formation of reactants. C. The equilibrium shifts in the exothermic direction. D. The equilibrium shifts in the endothermic direction.

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Ccording to Le Chatelier’s principle, what happens when the concentration of a product is reduced in a chemical reaction that was in equilibrium? A. The equilibrium shifts to the right to favor the formation of products. B. The equilibrium shifts to the left to favor the formation of reactants. C. The equilibrium shifts in the exothermic direction. D. The equilibrium shifts in the endothermic direction.

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1. If 500 ML of a 3 L sample of 0.20 M sodium chloride solution is spilled, what is the concentration of the remaining solution? A. 300 M B. .033 M C. 15.2 M D. .20 M

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D. 0.2 MThe concentration of a solution is basically the ratio of the solute present to the solvent in the solution. This is an intrinsic property, independent of the amount of solution that is present. A similar example is that of density. No matter the size of a sample, the density and concentration of that sample remain constant.

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The rate constant for the second-order reaction 2no2(g) ? 2no(g) o2(g) is 0.540/(m · s) at 300°c. how long (in seconds) would it take for the concentration of no2 to decrease from 0.500 m to 0.250 m

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Answer:

The coefficient of CO₂ is 5.

Explanation:

    Balancing the reaction:

___C₅H₁₂ + ___O₂ → ___CO₂ + ___H₂O

There are 5 C in the left side, so we put 5 on the right side:

___C₅H₁₂ + ___O₂ →  5CO₂ + ___H₂O

There are 12 H in the left side, so we put 6 as the coefficient of H₂O:

___C₅H₁₂ + ___O₂ →  5CO₂ + 6H₂O

Finally, there are 16 O in the right side, so we put 8 as the coefficient of O₂

___C₅H₁₂ + 8O₂ →  5CO₂ + 6H₂O

The coefficient of CO₂ is 5.

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A 0.89% (w/v) sodium chloride solution is referred to as physiological saline solution because it has the same concentration of salts as human blood. what is the molarity of a physiological saline solution? (note: w/v means mass to volume)

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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The decomposition of so2cl2 is first order in so2cl2 and has a rate constant of 1.42 x 10^-4 if the initial concentration of so2cl2 is 1.00 m how long will it take for the concentration to decrease to .78 m

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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Which statement best describes how a catalyst can speed up a chemical reaction? The catalyst makes lower energy pathways available. The catalyst increases the concentration of products. The catalyst binds to enzymes to release substrates. The catalyst increases the concentration of reactants.

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There are two systems in the human body that are responsible for the coordination between the functions of different systems to achieve the unity of the living organism’s body. These two systems are the nervous system and the endocrine system. The action of the nervous system is fast and takes a short time, while the action of the endocrine system is slow and takes a long time.

The functional unit of the nervous system is the nerve cell or the neuron. The neuron consists of a cell body and the axon. The cell body starts with the dendrites that receive the messages or the impulses from other neurons or from different sense organs or receptors. These impulses are then transmitted through the cell body. The cell body contains a nucleus and different organelles which help the nerve cell to perform its functions. The nerve impulse is then transmitted to the axon.

The axon is an extension from the cell body. There are some cells called Schwan cells that secrete a myelin sheath to insulate the axon from the surrounding medium. The insulated axons have more ability to conduct the impulses than non-insulated axons. The axon ends with the terminal arborizations. The terminal arborizations of a nerve cell connect to the dendrites of the next cell or to the afferent organ. The gaps between the dendrites and the terminal arborizations are called the synapses.

The nerve impulse is an electrochemical phenomenon i.e. an electrical phenomenon with a chemical nature. The membrane of the axon acts as a barrier between an outside positively charged medium and an inside negatively charged medium. This makes a potential difference of  -70mV. This state is called the resting potential. When the membrane is subjected to a stimulus, the positive charges enter to inside and the negative charges exit to the outside. The potential difference now becomes +40mV. This state is called the depolarization state. The point of stimulation acts as a new stimulus for the next point and so on. The membrane sooner gains its permeability again and the positive charges return to the outside and the negative charges to inside. This state is called repolarization.

The nerve impulse reaches the synapse. There are some neurotransmitters that are excited by the nerve impulse coming and carry the message across the membrane. Some receptors receive theses neurotransmitters on the dendrites of the next neuron. These receptors act as a stimulus for the new cell.

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If the rate-determining step limits the speed of a reaction, which statement is correct? Even if one or more fast steps occur in a reaction, the overall reaction cannot proceed any faster than the slowest step. If the first step is slow and the second step is fast, then the second step should determine the rate of the overall reaction. Increasing the concentration of a molecule that occurs in a fast step after a slow step will increase the overall rate of the reaction. In a unimolecular reaction where A decomposes to B and C, the rate of the reaction will decrease if the concentration of A is increased.

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A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

Answer: 47 kJ/mol

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Zachary has been trying to work on an essay for almost three hours, but he can’t seem to focus for more than 15 or 20 minutes at a time. What should he do so that the quality of his work doesn’t suffer because of poor concentration and lack of energy?

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Answer:

3 hours.          

Step-by-step explanation:

Let x be the time taken by shoe repairman to repair one pair.

We have been given that his assistant, who takes twice as long to repair a pair of shoes. So time taken by his assistant to repair one pair of shoes would be 2x.

The number of pair of shoes repaired by repairman in one hour would be frac{1}{x}.

The number of pair of shoes repaired by assistant in one hour would be frac{1}{2x}.

We have been given that together they can fix 16 pairs of shoes in an eight-hour day. We can represent this information in an equation as:

frac{1}{x}+frac{1}{2x}=frac{8}{16}

frac{1}{x}+frac{1}{2x}=frac{1}{2}

Let us have a common denominator.

frac{2*1}{2*x}+frac{1}{2x}=frac{1}{2}

frac{2}{2x}+frac{1}{2x}=frac{1}{2}

frac{2+1}{2x}=frac{1}{2}

frac{3}{2x}=frac{1}{2}  

Upon cross multiplying our equation we will get,

2x*1=3*2

2x=3*2

frac{2x}{2}=frac{3*2}{2}

x=3

Therefore, it take 3 hours for the repairman to fix one pair of shoes by himself.

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At 25 °C, what is the hydroxide ion concentration, [OH–], in an aqueous solution with a hydrogen ion concentration of [H ] = 4.2 × 10–9 M? [OH-] = ____ M

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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When 13.6 grams of kcl are dissolved in enough water to create a 180-gram solution, what is the solution’s concentration, expressed as a percent by mass? 4.6% kcl 6.8% kcl 7.6% kcl 8.2% kcl?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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If 3.0 liters of 0.50 m nacl (aq) is mixed with 9.0 liters of 0.2777 m nacl (aq), what is the final concentration of the resulting solution?

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If 3.0 liters of 0.50 m nacl (aq) is mixed with 9.0 liters of 0.2777 m nacl (aq), what is the final concentration of the resulting solution?

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The protein that maintains proper proportion and concentration of water in blood is

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Answer:

Helicases unwind the two parental DNA’s strands and creates the replication fork; single strand binding proteins keep the single strand from joining.


Further information:

• DNA replication: a biological method occurring in all living organisms that is the basis for biological inheritance

Helicase: It is an enzyme that may unwinds the DNA helix ahead of the replication machinery.

Origin of replication: a specific sequence in a genome at which replication is started.


Steps of DNA replication:

• During initiation, proteins fix to the source of replication while helicase unwinds the DNA helix and two replication forks are formed at the source of replication.

• During elongation, a primer sequence is added with complementary RNA nucleotides, which are then substituted by DNA nucleotides.

• During elongation the leading strand is made constantly, while the lagging strand is made in portions called Okazaki fragments.

• During termination, primers are detached and substituted with new DNA nucleotides and the backbone is stuck down by DNA ligase.

Purpose of DNA replication:

The purpose of DNA replication is to produce two duplicate copies of a DNA molecule. This is essential for cell division during development or repair of damaged tissues. DNA replication ensures that each new cell receives its own replica of the DNA.

Answer details:

Subject: Biology

Level: High school

Keywords:

• DNA replication

• Helicase

• Origin of replication

• Steps of DNA replication

Learn more to evaluate:

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brainly.com/question/10652950

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The signs of cognitive (mental) stress include all of the following EXCEPT: A. loss of memory B. loss of concentration C. poor judgment D. isolation

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According to Jean Piaget, around age 11, the fourth stage of cognitive development, the formal-operational stage begins.
This is the stage that starts at around 11, and lasts into the adulthood and the rest of a human’s life. During this period, people start understanding abstract concepts, develop logical thought, as well as deductive reasoning, which are all important for the years to come.

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Why did General Eisenhower force German civilians to visit liberated concentration camps?

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Why did General Eisenhower force German civilians to visit liberated concentration camps?

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Abnormally low blood sodium concentration is known specifically as​

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Abnormally low blood sodium concentration is known specifically as​

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A solution with a higher concentration of hydroxide ions (oh-) than hydrogen ions (h+)

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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Vonda is concerned about the safety of over-the-counter medications for children. she knows that one particular drug has been associated with liver toxicity and that the manufacturers of this drug have voluntarily reduced the concentration used in children’s formulations. what is this drug?

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This is completely false.

Legal Medications can come with many risks.

For example, oxycodone, a painkiller, is very similar to heroin in the risk of addictiveness as well as abusability.

The same being with amphetamines (adderall/dexedrine) to meth.

Just because it is legal, does not mean it is any safer or more dangerous.

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Your blood alcohol concentration depends on

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Answer:

to torture and eliminate Jews

Explanation:

A concentration camp or internment camp is a detention or confinement center where people are locked up because they belong to a generic collective instead of their individual acts, without prior trial and without judicial guarantees, although there may be an integrated legal coverage in a system of political repression. Concentration camps are often used to lock up political opponents, specific ethnic or religious groups, people of a certain sexual orientation, prisoners of war, civilians living in a region in conflict or other collectives.

Unlike a prison camp, which is used as a detention center for enemy soldiers in a conflict, a concentration camp is used mostly for the detention of non-combatants, although in some historical periods they were also used to imprison prisoners of war. war. They are publicly known detention centers, usually large.

The work camp is considered a variant, a concentration camp where prisoners are subjected to forced labor, often in deplorable conditions.

Due to the mistreatment of the civilian population during the Second World War, the Fourth Geneva Convention was drafted in 1949, specifically legislating on the treatment of the civilian population by the warring parties in a conflict.

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What process measures the amount of a solution of known concentration required to react with a measured amount of a solution of unknown concentration?

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This problem is to apply Roult’s Law.

Roult’s Law states that the vapor pressure, p, of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent, Po solv, times the mole fraction of the solvent, Xsolv

p = Xsolv * Po sol

X solv = number of moles of solvent / number of moles of solution

The solvent is water and the solute (not volatile) is glycerin.

Number of moles = mass in grams / molar mass

mass of water = 132 ml * 1 g/ml = 132 g

molar mass of water = 18 g/mol

=> number of moles of water = 132 g / 18 g/mol = 7.33333 mol

mass of glycerin = 27.2 g

molar mass of glycerin:, C3H8O3: 3 * 12 g/mol + 8 * 1 g/mol + 3*16 g/mol = 92 g/mol

number of moles of glycerin = 27.2g / 92 g/mol = 0.29565

total number of moles = 7.33333 moles + 0.29565 moles = 7.62898 moles

=> X solv = 7.33333 / 7.62898 = 0.96125

=> p = 0.96125 * 31.8 torr ≈ 30.57 torr ≈ 30.6 torr.

Answer: 30.6 torr

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How much water should be added to 14mL of 15% alcohol solution to reduce the concentration to 7%

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Answer:

Option C – BD=76 cm

Step-by-step explanation:

Given : You are designing a diamond-shaped kite. you know that AD = 44.8 cm, DC = 72 cm, and AC = 84.8 cm.

To find : How long BD should it be?

Solution :

First we draw a rough diagram.

The given sides were AD = 44.8 cm, DC = 72 cm and AC = 84.8 cm.

According to properties of kite

Two disjoint pairs of consecutive sides are congruent.

So, AD=AB=44.8 cm

DC=BC=72 cm

The diagonals are perpendicular.

So, AC ⊥ BD

Let O be the point where diagonal intersect let let the partition be x and y.

AC= AO+OC

AC=  x+y=84.8 …….[1]

Perpendicular bisect the diagonal BD into equal parts let it be z.

BD=BO+OD

BD=z+z

Applying Pythagorean theorem in ΔAOD

where H=AD=44.8 ,P= AO=x , B=OD=z

H^2=P^2+B^2

(44.8)^2=x^2+z^2  ………[2]

Applying Pythagorean theorem in ΔCOD

where H=DC=72 ,P= OC=y , B=OD=z

H^2=P^2+B^2

(72)^2=y^2+z^2 …………[3]

Subtract [2] and [3]

(72)^2-(44.8)^2=y^2+z^2-x^2-z^2

5184-2007.04=(x+y)(x-y)

3176.96=(84.8)(x-y)

37.464=x-y ……….[4]

Add equation [1] and [4], to get values of x and y

x+y+x-y=84.8+37.464

2x=122.264

x=61.132

Substitute x in [1]

x+y=84.8

61.132+y=84.8

y=23.668

Substitute value of x in equation [2], to get z

(44.8)^2=x^2+z^2

(44.8)^2=(23.668)^2+z^2

2007.04-560.174224=z^2

z=sqrt{1446.865776}

z=38.06

We know, BD=z+z

BD= 38.06+38.06

BD= 76.12

Nearest to whole number BD=76 cm

Therefore, Option c – BD=76 cm is correct.

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How much water should be added to 14 mL of 15% alcohol solution to reduce the concentration to 7%?

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How much water should be added to 14 mL of 15% alcohol solution to reduce the concentration to 7%?

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What is the highest concentration of medication?

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Answer:

High School P has the most consistent attendance among its students.

School N should be awarded for the highest average attendance.

Step-by-step explanation:

Consider the provided information.

Part A: If the school district wants to award the school that has the most consistent attendance among its students, which high school should it choose and why? Justify your answer mathematically.

Standard deviation (σ) is a measure of how a data set is spread out.

If the standard deviation is low, this implies that the information tends to be near to the set mean, whereas a high standard deviation implies that the information points are spread across a wider spectrum of values.

Therefore, for more consistency we need to look for the low standard deviation.

From the provided table we can see that the school P has low standard deviation (σ) i.e 31.5

Hence, High School P has the most consistent attendance among its students.

Part B: If the school district wants to award the school with the highest average attendance, which school should it choose and why? Justify your answer mathematically.

The formula for mean is:

Mean=frac{x_1+x_2+...+x_n}{n}

Mean is the same as average.

The sum of mean or average will be larger if each students contributes more attendance.

For highest average attendance the school with higher mean should be awarded.

Hence, School N should be awarded for the highest average attendance.

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