Calculate the molality of each of the following aqueous solutions (a) 2. 50 m nacl solution (density of solution = 1. 08 g/mL) (b) 48. 2 percent by mass KBr solution

Answers

Answer 1

The molarity of 2. 50 m NaCl solution is 2.68 molal and 48. 2 percent by mass KBr solution is 7.82 m.

Molality = moles solute / kg solvent  

Assume we have 1000 ml of solution.

1000 ml ₓ 1.08 g/ml = 1080 g

Now find the mass of NaCl:

2.50 M NaCl = 2.50 mol/L and 2.50 mol/L x 1 L = 2.50 moles of NaCl

molar mass NaCl = 58.4 g/mol, therefore mass NaCl present = 2.50 mol ₓ 58.5 g/mol = 146 g NaCl

Now find the mass of H₂O:

grams H₂O present = 1080 g - 146 g = 934 g H2O = 0.0.934 kg

We now have moles NaCl and kg H₂O

Molality  = 2.50 mol / 0.934kg = 2.68 molal

48.2% by mass of KBr means 48.2 g KBr / 100 g solution

To find molality, we need moles of KBr and kg of H₂O.  We can easily find he moles of KBr from the mass and the molar mass.

If we have 100 g solution, 48.2 g is KBr so the rest is H₂O.

100 g - 48.2 g = 51.8 g H₂O and this is equal to 0.0518 kg H₂O

Moles KBr = 48.2 g KBr ₓ 1 mol KBr/119 g = 0.405 moles KBr

Molality = 0.405 moles KBr / 0.0518 kg H₂O = 7.82 m

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Related Questions

Hypothesize as to why Seaborg removed the actinide and lanthanide series elements and placed them into their own block!

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This is currently going ok because how the pencil is working on it and how the pencil has a different color and how the ink looks in different ways so it doesn’t have a lot to work on but it’s really nice and I like it because it looks really good and it doesn’t have any of that weird stuff that I don’t know what it is by people’s pencil are disgusting because they put burgers on them like come on guys we in high school

How many ATP does glycolysis produce 4 ATP?

Answers

Energy is released when glycolysis occurs, and this energy is utilized to create four molecules of ATP. As a result, glycolysis produces a net gain of two ATP molecules.

What is glycolysis?

The metabolic mechanism that transforms glucose to pyruvate is known as glycolysis. This free energy is utilized to create the high-energy molecules adenosine triphosphate and reduced nicotinamide adenine dinucleotide. Glycolysis is a series of 10 enzyme-catalyzed processes. The initial stage in the breakdown of glucose to extract energy for cellular metabolism is glycolysis. Glycolysis is divided into two phases: energy-requiring and energy-releasing. Glycolysis is the process of breaking down glucose to create energy. It generates two pyruvate molecules, ATP, NADH, and water. The process occurs in a cell's cytoplasm and does not require oxygen. It can be found in aerobic and anaerobic organisms.

Here,

When glycolysis happens, energy is released, and this energy is used to build four molecules of ATP. As a result of this, glycolysis generates a net gain of two ATP molecules.

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The gas in a 250.0 mL piston experiences a change in pressure from 1.00 atm to 4.90 atm. What is the new volume (in mL) assuming the moles of gas and temperature are held constant

Answers

The gas in a 250.0 mL piston experiences a change in pressure from 1.00 atm to 4.90 atm. 56.2 ml is the new volume (in mL) assuming the moles of gas and temperature are held constant.

What is Boyle's law ?

Boyle's law states that at a given temperature, the volume of a gas and its pressure are inversely proportional.

Robert A. Boyle discovered the law in 1662, which states that at a constant temperature, the volume of a gas is inversely proportional to the pressure exerted by the gas.

Given:

Initial volume (V₁) = 250 mL

Initial pressure (P₁) = 1.00 atm

Final volume (V₂) = ?

Final pressure (P₂) = 4.45 atm

Assuming the gas has an ideal behavior, we can find the final volume by using Boyle's law as follows:

P₁ × V₁ = P₂ × V₂

V₂ = P₁ × V₁/P₂

V₂ = 1.00 atm × 250 mL / 4.45 atm

V₂ = 56.2 ml

Thus, 56.2 ml  is the new volume (in mL) assuming the moles of gas and temperature are held constant.

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Which of the following would be a reasonable unit for the rate constant of a second order reaction?
1. mol/L.sec
2. mol2/sec.L2
3. 1/sec
4. L/mol.sec
5. L2/mol2.sec

Answers

Option (4) is correct. The rate constant of a second order reaction has the unit  L/mole. sec.

In the Second order reaction the rate is proportional to the square of the concentration of one reactant. Rate of Second order reaction  is proportional to the product of the concentrations of two reactants. Such reactions generally have the form,

A + B → products.

Each monomer combines to form a larger molecule is called dimer. For the units of the reaction rate to be moles per liter per second (M/s), the units of a second-order rate constant must be the inverse (M−1·s−1). Because the units of molarity are expressed as mole/L, the unit of the rate constant can also be written as L(mole ·s).

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What actions do you take immediately after a burn occurs?

Answers

Cool in cold or lukewarm water for 20 minutes.

This should be done as soon as possible after an injury. Never use ice, ice water, cream, or greasy substances like butter on the burn. Be careful to keep the airways open when treating burn victims. Associated smoke inhalation injuries are very common, especially when the patient is burned in an enclosed space such as a room or building. Even people who have been burned outdoors can inhale smoke. Stop the burning process as soon as possible. Remove all clothing and jewelry near the burned area.

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A gas mixture containing oxygen, nitrogen, and He has a total pressure of 189.9 kPa. If PO2 = 104.6 kPa and PN2 = 13.0 kPa, what is PHe ?

Answers

A gas mixture containing oxygen, nitrogen, and He has a total pressure of 189.9 kPa. If PO2 = 104.6 kPa and PN2 = 13.0 kPa, PHe is 72.3 kPa.

What is total pressure ?

Static pressure and velocity pressure are added to create total pressure. There is static pressure in a fluid that is not flowing. The pressure required to accelerate air from a zero velocity to a specific velocity that is proportional to the kinetic energy of the air stream is known as velocity pressure.

Consider the friction that exists between a fluid and the interior surface of a pipe. The fluid's density and velocity are used to compute the dynamic pressure: the total pressure in a mixture of ideal gases is the total of the partial pressures of the individual gases.

Total pressure = PO2  + PN2 + PHe

189.9 kPa = 104.6 kPa + 13.0 kPa + PHe

PHe = 72.3 kPa

Thus, A gas mixture containing oxygen, nitrogen, and He has a total pressure of 189.9 kPa. If PO2 = 104.6 kPa and PN2 = 13.0 kPa,PHe is  72.3 kPa.

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Which of the following ions has the largest radius?
a. Na+
b. K+
c. CS+
d. Li+

Answers

The size of an ion is determined by its atomic radius, which is a measure of the size of the atom from which the ion is formed. The atomic radius of an atom is generally determined by the size of its electron cloud. The size of the electron cloud is influenced by the number of electrons and the energy levels they occupy.

Of the ions given, Li+ has the smallest atomic radius because it has the smallest number of electrons and the highest effective nuclear charge, which means that its electrons are held more closely to the nucleus. Na+, K+, and CS+ have larger atomic radii than Li+ because they have more electrons and lower effective nuclear charges, which means that their electrons are held more weakly by the nucleus.

Therefore, the answer is CS+ has the largest radius.

Sulfuryl chloride is in equilibrium with sulfur dioxide and chlorine gas: so2cl2(g) so2(g) + cl2(g) a system with a volume of 1. 00 l is in equilibrium at a certain temperature with p(so2cl2) = 1. 00 bar and p(so2) = p(cl2) = 0. 10 bar. By how much will the number of moles of so2cl2 at equilibrium change if the volume is reduced to 0. 50 l? (a) increase 1-10% (b) increase 11-50% (c) decrease 1-10% (d) decrease 11-50%

Answers

The volume is decreased to 0. 50L, the number of moles of SO₂Cl₂at equilibrium will increase by 1–10% option - a is correct.

What is Le Chatelier's Principle.

The guiding idea of Le Chatelier is as follows: A shift in the position of the equilibrium results from a change in one of the variables that characterize a system in equilibrium and cancels out the effects of that change.

Now to solve this question first we have to know the Le-chatelier's

Principle

The Principal that if a system in chemical equilibrium is subjected to a disturbance it tends to change in a way that opposes this disturbance.

SO₂Cl₂(g) ⇄ SO₂(g) + Cl₂(g)

Initially, there is one molecule at the left hand side of the reaction and two molecules are on the right. But, the Partial pressure of molecules on RHS is lower than LHS. Concentration of RHS molecules is Lower, forward reaction is more favorable.

Decreasing volume would result in increasing the total pressure.

Now, according to Le chatelier's Principle, the equilibrium will shift in such a way to oppose change under compression. Since there are more moles of Products than reactants, to counteract the increased pressure. The equilibrium will shift to LHS increasing the moles

of SO₂Cl₂ but since the concentration (Partial Pressure)

of SO₂Cl₂, it will not increase more than 10%

Hence, answer will be (a) Increase 1-10%.

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Describe the physical properties of matter using the graphic organizer below
indicate whether each property can be used to identify a substance, $6.6.864
Mass
Weights
Mass and Weight
Magnetism
Density

Answers

Physical properties  such as  mass, weights , density can be common for one or more substances hence cannot be used for identification while magnetism is unique for each substance ,hence used for identification.

What are physical properties?

Any property which describes the state of a physical system is called as a physical property.Changes in physical properties are used to describe changes between the states. They are often related to as observable properties.

Physical property which can be quantified is a physical quantity. These are also classified further with respect to their directionality. Physical properties are differentiated from chemical properties by the way they determine how a substance behaves in a chemical reaction.

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the safety air bag in automobiles are inflated by nitrogen gas by the rapid decomposition of sodium azide:

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sodium azide (NaN3) is used to inflate the safety airbags in automobiles (g) This airbag should be filled with N2 at a pressure of 1.15 atm and temperature of 26.0°C. It has a volume of 36 L.

Modern automobiles use numerous technical components and subsystems, each of which performs a specific design function. Some of these have thousands of individual pieces and were made possible by new or improved technologies, such as electronic computers, high-strength polymers, and novel alloys of steel and nonferrous metals. Air pollution, safety regulations, and global manufacturer competition, among other things, have all contributed to the development of some subsystems.

With an estimated 1.4 billion in use worldwide, passenger vehicles have become the main form of family transportation. In the United States, where more than three trillion miles (almost five trillion kilometers) are traveled annually, roughly one-fourth of these are located.

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Among the following radioactive parent isotopes, which has the shortest half-life?A) uranium-238B) potassium-40C) rubidium-87D) carbon-14

Answers

The half-life of a radioactive isotope is the time it takes for half of the original number of atoms in a sample to decay.

The isotope with the shortest half-life among the given options is:

D) carbon-14

The half-life of carbon-14 is 5,730 years which is shorter than the other isotopes. Uranium-238 has a half-life of 4.5 billion years, potassium-40 has a half-life of 1.25 billion years and rubidium-87 has a half-life of 49.8 billion years, all are greater than the half-life of carbon-14.

So, carbon-14 is the isotope with the shortest half-life among the given options.

It is important to note that the half-life of an isotope is a constant property of the isotope. For example, the half-life of carbon-14 is always 5,730 years and does not change with the amount of carbon-14 present or any other factors.

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does calcium oxide reacts with carbon monoxide

Answers

CALCIUM OXIDE AND CARBON MONOXIDE

Yes, calcium oxide (CaO) reacts with carbon monoxide (CO) to form calcium carbonate (CaCO3) and oxygen gas (O2). The reaction can be represented by the following equation:

CaO + CO -> CaCO3 + O2

This reaction is an example of a chemical change, as it results in the formation of a new substance with different chemical properties. The reaction is also exothermic, meaning that it releases heat.

Calcium oxide is a white solid that is used in a variety of applications, including cement production and the purification of flue gases. Carbon monoxide is a colorless, odorless gas that is toxic to humans when inhaled. It is produced as a byproduct of the incomplete combustion of fossil fuels.

Hope This Helps You!

Yes calcium Oxide reacts with carbon monoxide

A car has a mass of 2,050 kg and is traveling at 28 meters per second. What is the car's kinetic energy?

Answers

After solving the equation the car's kinetic energy is 783,500 kg m2/s2.

What is kinetic energy?

Kinetic energy is the energy of motion, or the energy associated with an object or system due to its motion. It is a form of energy that can be converted into other forms of energy, such as thermal energy, sound energy, electrical energy, and so on.

The car's kinetic energy is the energy it has due to its motion. Kinetic energy is calculated as KE = 1/2mv2, where m is mass and v is velocity. In this case, the car has a mass of 2,050 kg and is traveling at 28 meters per second. Plugging these values into the equation gives:
KE = 1/2(2050 kg)(28 m/s)2
= 1/2(2050 kg)(784 m2/s2)
= 783500 kg m2/s2
Therefore, the car's kinetic energy is 783,500 kg m2/s2.

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Determine the number of atoms of each element in the following: 3CO3

Answers

The coefficient is distributed to each of the elements, while the subscript is only that element. A coefficient of 3 multiplied to C and O. There are 3 carbon atoms. For oxygen, it also has a subscript, meaning you multiply the coefficient by the subscript to get 9 oxygen atoms

Give the ΔH value for the combustion of ethanol as shown in the reaction C2H5OH(g)+3O2(g)⟶Δ2CO2(g)+3H2O(g)+1278 kJ .
Express your answer using four significant figures. If the value is positive, do not include the + sign in your answer.

Answers

The value of the ΔH for the reaction is obtained as 1278 kJ .

What is the value of ΔH?

We have to note that the enthalpy change of the reaction has to do with the heat that ahs been evolved or absorbed in a reaction. In this case we have to obtain the enthalpy change by looking at the combustion reaction that has been shown here.

It is clear that from the thermochemical reaction equation, there is the evolution of about 1278 kJ of heat in the process of the reaction as shown in the question that we have above.

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Is this water or oil

Answers

Answer:

it is oil.

Explanation:

it is oil because if water was written that would be wried so I think it is oil.

Which argument supports the claim that dissolving calcium chloride (CaCl2) in water is a chemical change

Answers

The argument that supports the claim that dissolving solid calcium chloride (CaCl2) in water is a chemical change is A. The ionic bond among calcium and chloride ions has been broken..

When solid calcium chloride is added to water, the ionic bonds between the calcium ions (Ca2+) and chloride ions (Cl-) are broken apart by the polar water molecules. The calcium ions and chloride ions are then surrounded by the water molecules, forming a new chemical compound called calcium chloride hydrate (CaCl2*xH2O) which is different from the original solid calcium chloride. This process is a chemical change because it creates new substances and the original chemical bonds are broken and new bonds are formed.

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the complete question is:

Which of the following arguments supports the claim that dissolving calcium chloride (CaCl2) in water results in a chemical change?

A. The ionic bond among calcium and chloride ions has been broken.

B. By evaporating the water, the solid calcium chloride can be recovered.

C. The ions found in the solid remain in the solution and have not changed.

D. Ions are attracted by the polar water molecules.

What are two characteristics of the rock found 3 mya?

Answers

To solve this we must be knowing each and every concept related to rock and its characteristics. Therefore, the two characteristics of the rock can be given as below.

What is rock?

The word rock relates to the material's bulk volume, which includes the grain or crystals in addition to the enclosed vacuum space.

The two characteristics of the rock are:

Some minerals exhibit color features related to mineral composition and atom arrangement: for example, magnetite is black, chlorite is green, and pyrite is brassy yellow.

The capacity of a mineral to resist scratching is used to estimate its hardness, which is generally determined on fresh material. When a mineral is scraped with a knife, it softens. If a knife cannot scratch it, the two have equivalent hardness or even the mineral is harder.

Therefore, the two characteristics of the rock can be given as above.

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The following reaction occurred when a strip of aluminum was placed in a nickel solution. Which half-reaction represents the oxidation that has occurred in the reaction?

Answers

The reaction that shows oxidation is the one that has been shown in option D.

What is oxidation?

We have to know that the process that we call oxidation would have to do with the loss of the electrons that we have in a system. If we are dealing with a neutral atom that has been oxidized then we would see an increase in the oxidation number of the atom. This same effect would be seen if we are looking at the oxidation of any other chemical specie that is under consideration.

Ni lost and electronNi^2+ was formedA total of two electrons were lost in the process.

We need to look at the reactions that have been shown in the options that we have and then compare it with the overall redox reaction equation that we see at it has been shown in the reaction that has been attached to the question that we have in the attachment that is shown above here.

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Early chemists, known at the time as alchemists, had a difficult time understanding the Law of Conservation of Mass. Using the burning of wood as an example, what property of matter made this law difficult for early scientists to understand?

Different types of wood burned differently.

Wood is heavier than ash.

The fire was too bright to observe the reaction.

The gases produced escaped to the atmosphere.

Answers

Answer:

The gases produced escaped to the atmosphere.

Which element has a violent reaction when combined with cold water ?____
Base your answers to the following questions on the electron configurations below:
(A)2s1
(B)[Ar] 3d104s24p1
(C)[Kr] 4d105s25p3
(D)[Ne] 3s2
(E)[Kr]4d105s25p6

Answers

The element with electronic configuration 2s1, which is lithium, has a violent reaction with cold water.

The most reactive metals in the periodic table are the alkali metals (Li, Na, K, Rb, Cs, and Fr); they all react with cold water violently or even explosively, displacing hydrogen. In the reduction of water to hydrogen gas (H2) and the metal ion hydroxide (OH), Group 1 Metal (M) is oxidised to its metal ions.

The second most reactive metals in the periodic table are the alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra), which also exhibit increased reactivity in higher periods like the Group 1 metals. The only alkaline earth metal that does not react with water or steam, even when heated to a high temperature, is beryllium (Be).  Furthermore, beryllium has an exterior oxide layer that is robust, which reduces its reactivity at lower temperatures.

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2POCl3(g)---> 2PCl3(g)+O2(g), deltaH_o=572 kJ, delta S_o=179 J/K
At what temperature (if any) would the decomposition of POCl3 become spontaneous?

Answers

At T=3195.53 Kelvin, decomposition of PoCl3 becomes spontaneous.

What is meant by spontaneous?

In chemistry, spontaneous processes is one that occurs without addition of external energy. Spontaneous process can occur quickly or slowly, because spontaneity is not related to the kinetics or reaction rate.

Spontaneous reaction happens in given set of conditions without interruptions whereas the nonspontaneous reaction occurs with the help of external agents like heat or energy.

Given, ∆H=572KJ and ∆S=0.179J/K

According to thermodynamical concept;

As, T=∆H/∆S,

=572/0.179

= 3195.53 Kelvin

We know, change in Gibbs free energy (∆G)=0 ; which shows that reaction is in equilibrium.

Above this temperature the reaction becomes spontaneous and moves in  forward direction.

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Convert the following numbers into the standard form of scientific notation 0. 010x 10e5

Answers

The standard form of scientific notation for 0. 010x 10e5 is 1.0 × 10^3.

Scientific notation is a form of presenting large numbers or very small numbers in a simpler form.

There are some rules to write scientific notation:

The base should be always 10. The exponent must be a non-zero integer.

Absolute value of the coefficient should be greater than or equal to 1 but it should be less than 10.The mantissa carries the rest of the significant digits of the number.

The power of 10 will be positive, if the given number is multiples of 10 then the decimal point has to move to the left. The power of 10 will be negative If the given number is smaller than 1 and then the decimal point has to move to the right.

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How many ATP does ATP produce?

Answers

The bulk of ATP production occurs during cellular respiration within the mitochondrial matrix, producing around thirty-two ATP molecules for every molecule of oxidized glucose.

What is ATP?

The energy currency of the cell is ATP (adenosine triphosphate). It is a natural chemical molecule made up of phosphate groups, adenine, and the sugar ribose. These molecules supply energy to the body's many metabolic operations. Therefore, it is dubbed "Energy Currency of the Cell". ATP can be utilized to store energy for future reactions or it can be used to pay for reactions when the cell need energy. Animals use ATP to store the energy received from food breakdown. Similarly, plants use ATP molecules to collect and store the energy they receive from light during photosynthesis.

Here,

The majority of ATP is produced during cellular respiration within the mitochondrial matrix, which produces around thirty-two ATP molecules for every molecule of oxidized glucose.

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Examine the phase diagram for the substance Bogusium (Bo) and select the correct statement Pressure 760 ton AL C. •D Temperature O Point B represents the triple point for Bo. O Bo changes from a solid to a gas as one follows the line from C to D. O Bo changes from a solid to a liquid as one follows the line from C to D.
O Bo(s) has a lower density than Bol). O The triple point for Bo is at a higher temperature than the melting point for Bo.

Answers

The triple point of a substance is the temperature and pressure at which all three phases of the substance (solid, liquid, and gas) can coexist in equilibrium.

Point B on the phase diagram is the triple point for Bogusium, represented by the intersection of three lines, which indicates that all three phases can coexist in equilibrium at this point.

1. A triple point of a substance is the temperature and pressure at which all three phases of the substance can coexist in equilibrium.

2. Point B on the phase diagram is the triple point for Bogusium, represented by the intersection of three lines.

3. This indicates that all three phases can coexist in equilibrium at this point.

4. Therefore, the correct statement is that Point B represents the triple point for Bo.

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How many hydrogen atoms are in 1 mg of aspartame?

Answers

Change mg—-> moles then moles—-> no.molecules by these rules 1)MOLES=MASS/MOLAR MASS 2)NO.MOLECULES=MOLESXAVOGADROS NUMBER

Which of the following substances would you expect to have a nonzero dipole moment? Check all that apply.
O Chloroethane, CH3 CH2C1 O XeF4 O Cl20
BF3

Answers

O Chloroethane, CH3CH2Cl, O XeF4 of the following substances would expect to have a nonzero dipole moment

A substance with a non-zero dipole moment means that the electrons are not distributed symmetrically in the molecule, resulting in a partial positive charge on one end and a partial negative charge on the other end. Chloroethane, CH3CH2Cl has a polar covalent bond between C-Cl and since the C-Cl bond is polar the overall molecule is polar and thus has a nonzero dipole moment.O Chloroethane, CH3 CH2C1 O XeF4 O Cl20. BF3XeF4 has a tetrahedral electron pair geometry, with 4 polar covalent bond Xe-F, and since all the F atoms are in the same plane as the Xe atom, the molecule is polar and thus has a nonzero dipole moment. Cl20 has a polar covalent bond Cl-Cl but since the molecule is symmetric the overall dipole moment is zero. BF3 has a trigonal planar electron pair geometry, with 3 polar covalent bond B-F, but since the molecule is symmetric the overall dipole moment is zero.

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A student dissolved 0.178 grams of a solid monoprotic acid in water and then titrated it. They then performed the same calculation as you just did in question 2 to find the moles and they found that 0.00685 moles were neutralized. What is the molar mass of the unknown acid that was dissolved? (Hint: What are the units for molar mass?)

Answers

Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.

What is mole?

The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.

Mathematically,

mole =given mass ÷ molar mass

Molar mass of  unknown acid= ?

mass of  unknown acid= 0.178 grams

moles of  unknown acid= 0.00685 moles

Substituting the values in above formula we get

0.00685  = 0.178  ÷ molar mass

molar mass=25.98g/mol

Therefore, 25.98g/mol is the molar mass of the unknown acid that was dissolved.

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2. How many moles of helium are present in a balloon at STP if the volume is 3.7 L? Please show all work!

Answers

Using the Ideal Gas Law equation: [tex]PV=nRT[/tex]

P = pressure (kPa)V = volume (L)n =  moles (mol)R = gas constant( [tex]\frac{kPaL}{molK}[/tex])T = Temperature (K)

STP also known as Standard Temperature  and Pressure is a set of conditions at sea level

At STP:

P = 101.3 kPa

T = [tex]0^o C[/tex] or 273 K

[tex]n=\frac{PV}{RT}[/tex]

[tex]n=\frac{101.3kPa)(3.7L)}{(8.31\frac{kPaL}{molK})(273K)}[/tex]

[tex]n = 0.16 mol[/tex]

How did the experiement with boiling water compare with the experiment in which magnesium was added to hydrochloric acid

Answers

In the experiment with boiling water and the experiment in which magnesium was added to hydrochloric acid both resulted in gas formation.

Hydrochloric acid and magnesium in a balanced chemical reaction

[tex]MgCl_{2}[/tex] + [tex]H_{2}[/tex] = Mg + 2HCl (g).

A gas is hydrogen . This reaction is exothermic (energy is released). New compounds are being produced due to chemical change.

Nothing new is created when water is heated to a boil. Heat is added in this endothermic reaction. Gas is steam. Both experiments a gas is released. One is a chemical change the other is a physical change. One is exothermic while other is endothermic.

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Reuben bought 6 boxes of chocolates. Each box cost $7.36. How much did he spend? How many moles of CH3CH2OH are contained in 548 mL of 0.0788 M CH3CH2OH solution? Spring constant problem. What is the formula for k in terms of the period T and the mass?A. K= 4pi^2m/T^2B. K= 4*pi^2/mT^2C. K= 2*pi*m/T prepare a list of various sources of energy that are used at your home .classify them into renewable and non renewable source of energy Which of the following is incorrect:A. Protons contribute to the mass of the atomB. Electrons have a negative chargec. Neutrons are found in the nucleus of the atomd. Electrons, neutrons and protons all have the same mass Given that f(x)=x, describe the function of g(x)shown on the graph.The function is represented by the equationg(x)=x +The function g(x) has a domain xThe function g(x) has a range y What were the major problems of the new nation under the Articles of Confederation? Why might Mississippi have required all African Americans to have labor contracts, but not white Mississippians If the work done to move a toy car by a force of 20N is 60J how far did the car move? The length of the rectangle is X units more than itswidth. The width of the rectangle is 11 units and thelength of the wire that is used to make this rectangleis a maximum of 57 units. Represent this situationusing an inequality. Why is eating a well balanced healthy diet important? What are some of the consequences or risks to an unhealthy diet?*1 paragraph answer* Question 9 of 10How did Muhammad change Arabic religion?A. He established Jerusalem.B. He established monotheism.OC. He created the Sunni religion.OD. He joined it with Christianity. Sport Soccer Jogging Walking Skiing Football Total Hrs 5 20 10 5 10 50 Calculate the portion for jogging in degrees [?] 20 hrs. Total Sport Hours "It doesn't matter what I need to do, I am going to do what I have to, to get what I want."In a couple of sentences, address that statement. Is it right? Is good? What problems can come from this way of thinking? apart from finding better weather what other things do animals migrate for answer What is Mendel's 1st and 2nd law? What is the central idea of the song Brother, Can You Spare a Dime? For the reaction given below, 2.00 moles of A and 3.00 moles of B are placed in a 6.00-L container. At equilibrium, the concentration of A is 0.246 mol/L. What is the concentration of B at equilibrium? A) 0.246 mol/L B) 0.325 mol/L C) 0.500 mol/L D) 0.492 mol/L E) none of these What is the main idea of social contract? I need help completing the square