Aluminium does not corrode in a normal atmosphere because: a) Aluminum is unreactive with oxygen b) The reaction with oxygen has too high and activation energy. c) The formation of an oxide layer inhibits further diffusion and corrosion d) None of the above

Answer:

Their antibody is composed by subunits that have molecular weights of 50 kD and 25 kD, and each of these subunits has one Cys residue at least.

Explanation:

Their antibody is composed by subunits that are conected by an S-S bond that takes place in their Cys residue. When the antibody is treated with a reducing agent, these S-S bond are reduced to S-H, thus the subunits are no longer connected to each other.

The original antibody weights 150 kD, as seen in Lane 1. And the combination of these subunits are seen in Lane 2: this means there is not only one subunit of 50 kD and one of 25 kD. Rather, these subunits are repeated in the antibody, in a way such that their combined weight add ups to 150 kD (for instance 2 subunits of 50 kD and 2 subunits of 25 kD).

Final answer:

Based on SDS-PAGE analysis, investigators can conclude that the antibody under study is a multimeric protein made of polypeptide chains with molecular weights of 50 kD and 25 kD, held together by disulfide bonds that were reduced by mercaptoethanol.

Explanation:

Investigators utilized SDS-PAGE to analyze the purity of an antibody preparation. Upon electrophoresis, Lane 1, which contained untreated antibody sample, showed a single band at 150 kD. However, Lane 2, with antibody treated with mercaptoethanol, exhibited two distinct bands at molecular weights of 50 kD and 25 kD. The presence of these two bands in Lane 2, which was absent in Lane 1, indicates that the antibody molecule was originally composed of multiple polypeptide chains held together by disulfide bonds. Mercaptoethanol reduced these disulfide bonds, allowing the constituent polypeptide chains to be separated under electrophoretic conditions and revealing the true subunit composition of the antibody. Therefore, the investigators can conclude that the antibody is a multimeric protein, likely composed of two 50 kD chains and at least one 25 kD chain that were originally connected by disulfide bonds.

Answer:

The organism died 35900 years ago

Explanation:

Plug-in all the values in the above equation:

[tex]0.013=(\frac{1}{2})^{\frac{t}{5730years}}[/tex]

So, t = 35900 years

Hence the organism died 35900 years ago

Answer:

A solvent is a chemical substance that has the ability to dissolve other chemical compounds, called solute, to form a solution.                

Solvents can be polar and non-polar in nature.

In general, polar solvents dissolve only polar solute molecules and non-polar solvents dissolve only non-polar solute molecules.

Highly polar solute molecule such as ionic compounds like NaCl and sugars, dissolve only in highly polar solvents with a large dielectric constant like water.

Therefore, because of the high dielectric constant of water, ionic compounds can be easily separated and dispersed.

Answer :

(a) The rate of reaction is, second order reaction.

(b) The rate of reaction is, zero order reaction.

Explanation :

Rate of reaction : It is defined as the rate of change in concentration of reactant or product with respect to time.

Order of reaction : It is defined as the sum of the exponents or powers to which the molar concentration in the rate law equation are raised to express the observed rate of reaction.

The order of reaction depends on the power of reactant concentration.

(a) The given rate expression is,

[tex]Rate=k[NO_2]^2[/tex]

From this expression we conclude that the power of concentration of reactant [tex]NO_2[/tex] is 2.  

That means it is a second order reaction.

(b) The given rate expression is,

[tex]Rate=k[/tex]

From this expression we conclude that the rate of reaction is equal to rate constant.

That means it is a zero order reaction.

The molar heat of vaporization of substance X can be determined using the Clausius-Clapeyron equation. The molar heat of vaporization of substance X is -61.78 kJ/mol.

The molar heat of vaporization of substance X can be determined using the Clausius-Clapeyron equation. The equation is given by:

ln(P₂/P₁) = -(ΔHvap/R)((1/T₂) - (1/T₁))

We can solve for ΔHvap by substituting the values given: P₁ = 100 mm Hg, T₁ = 1080 °C (or 1353 K), P₂ = 600 mm Hg, and T₂ = 1220 °C (or 1493 K).

ln(600/100) = -(ΔHvap/8.314)((1/1493) - (1/1353))

Solving for ΔHvap gives us a value of -61.78 kJ/mol. Therefore, the molar heat of vaporization of substance X is -61.78 kJ/mol.

Answer:

To maintain a pH value of 8.8 in a particular solution the best option is Tris or boric acid.

Explanation:

To decide a good acid/conjugate base pair it is necessary to know the pKa of the acids because every buffer has an optimal effective range due to pH = pKa ± 1. The closer the working pH is to the acid pKa, the buffer will be more effective. Below is the list of the pKa of the different option.

Acetic acid: pKa = 4.76

Boric acid: pKa1 = 9.24 pKa2 = 12.74 pKa3 = 13.80

Ascorbic acid: pKa1 = 4.17 pKa2 = 11.57

Tris:  pKa = 8.06

Acetic and Ascorbic acid are too far from the range of 8.8. Thus the best options are boric acid or Tris. To define between these two it is necessary to consider other factors like interaction between components of the solution and the ionic strength required.

Answer:

[tex](\rho*Q)/(\mu*h)[/tex]

Explanation:

First, we need to establish the unit of each variable:  

To eliminate [tex]m^3[/tex] we need to multiply Q by [tex]\rho[/tex]. Then to eliminate kg we divide [tex]\rho[/tex] by [tex]\mu[/tex]. Finally, multiply [tex]\mu[/tex] by h we can let the constant dimensionless.

Answer:

hhh

Explanation:

Pyranose is collective term for the saccharides which have chemical structure which includes six-membered ring that consists of one oxygen atom and five carbon atoms.

Furanose is collective term for carbohydrates which have chemical structure which includes five-membered ring system that consists of one oxygen atom and four carbon atoms.

Glucose exists both in pyranose and furanose form. It's structure is shown in image.

Answer:

497.01 seconds will it take light to move a distance of [tex]1.49\times 10^8 km [/tex]from the Sun to the Earth.

Explanation:

Speed of the light = 299,792,458 m/s

Time taken by the light to cover [tex]1.49\times 10^8 [/tex] kilometer = T

[tex]1.49\times 10^8km=1.49\times 10^{11} m[/tex]

Speed=[tex]\frac{Distance}{Time}[/tex]

[tex] 299,792,458 m/s=\frac{1.49\times 10^{11} m}{T}[/tex]

[tex]T=497.01 seconds[/tex]

497.01 seconds will it take light to move a distance of [tex]1.49\times 10^8 km [/tex]from the Sun to the Earth.

To determine how long light takes to travel from the Sun to the Earth at a speed of 299,792,458 m/s for a distance of 1.49 x 10^8 km, convert the distance to meters and divide by the speed of light. The result is approximately 497 seconds.

If light moves at a speed of 299,792,458 m/s, and we want to determine how long it will take light to travel a distance of 1.49 x 108 km from the Sun to the Earth, we must first convert the distance to meters (since the speed of light is given in meters per second). To do this, we multiply by 1,000 (since 1 km = 1,000 m), yielding a distance of 1.49 x 1011 m.

To find the time in seconds, we divide the distance by the speed of light, which gives us:

Time (seconds) = Distance (m) / Speed of light (m/s) = 1.49 x 1011 m / 299,792,458 m/s

Performing the calculation yields approximately 497 seconds, which is the time it takes for light to travel from the Sun to the Earth with the given information. We use the same number of significant figures as presented in the distance measurement, which in this case is two (1.49).

Answer: The mass of chlorine gas is 4.54 grams.

Explanation:

To calculate the mass of the gas, we use the equation given by ideal gas equation:

[tex]PV=nRT[/tex]

Or,

[tex]PV=\frac{m}{M}RT[/tex]

where,

P = pressure of the gas = 98.7 kPa

V = Volume of gas = 3.34 L

m = given mass of chlorine gas = ?

M = Molar mass of chlorine gas = 35.45 g/mol

R = Gas constant = [tex]8.31\text{ L kPa }mol^{-1}K^{-1}[/tex]

T = Temperature of the gas = [tex]37^oC=[37+273]=310K[/tex]

Putting values in above equation, we get:

[tex]98.7kPa\times 3.34L=\frac{m}{35.45g/mol}\times 8.31\text{ L kPa }mol^{-1}K^{-1}\times 310K\\\\m=4.54g[/tex]

Hence, the mass of chlorine gas is 4.54 grams.

Answer:

[tex]1.64x10^-^1^7 J[/tex]

Explanation:

Due to you know the velocity of the electron, the only thing that you need to do is used the Newtonian kinetic energy formula.  The kinetic energy is defined as the work needed by motion body of a given mass to accelerate from rest to its know velocity:

[tex]KE=1/2mv^2=[kg*(m/s)^2]=[J][/tex]

[tex]m_e_- =9.1093835x10^-^3^1 kg [/tex]

[tex]KE=9.11x10^-^3^1 kg*(6.00x10^6 m/s)^2=1.64x10^-^1^7 J[/tex]

Answer:

-2.3 ºC

Explanation:

Kf (benzene) = 5.12 ° C kg mol – 1

1st - We calculate the moles of condensed gas using the ideal gas equation:

n = PV / (RT)

P = 748/760 = 0.984 atm

T = 270 + 273.15 = 543.15 K

V = 4 L

R = 0.082 atm.L / mol.K

n = (0.984atm * 4L) / (0.082atm.L / K.mol * 543.15K) = 0.088 mol

Then, you calculate the molality of the solution:

m = n / kg solvent

m = 0.088 mol / 0.058 kg = 1.52mol / kg

Then you calculate the decrease in freezing point (DT)

DT = m * Kf

DT = 1.52 * 5.12 = 7.8 ° C

Knowing that the freezing point of pure benzene is 5.5 ºC, we calculate the freezing point of the solution:

T = 5.5 - 7.8 = -2.3 ºC

Answer:

4 × 10⁶ sec

Explanation:

The distance between the earth and the moon = 384,400 km

The speed of the peregrine falcon = 350 km/hr

Considering,

Distance = Speed × Time

So,

Time = Distance / Speed = 384,400 km / 350 km/hr = 1098.28571 hrs

Also,

1 hr = 3600 sec

So,

1098.28571 hrs = 3600 × 1098.28571 s ≅ 4 × 10⁶ sec

Thus time taken by peregrine falcon if falcon fly to the moon = 4 × 10⁶ sec

It would take the peregrine falcon approximately 3,953,044 seconds to fly to the moon at a speed of 350 km/hr.

If the peregrine falcon can travel up to 350 km/hr in a dive, let's calculate how long it would take for the falcon to fly to the moon at this speed. The average distance from Earth to the moon is approximately 384,400 km.

To find the time it would take, we can use the formula:

Time = Distance/Speed

So, Time = 384,400 km / 350 km/hr = 1098.29 hours.

Converting hours to seconds, we have:

Time = 1098.29 hours x 60 minutes x 60 seconds = 3,953,044 seconds.

Therefore, it would take the peregrine falcon approximately 3,953,044 seconds to fly to the moon at a speed of 350 km/hr.

Explanation:

Length of trash cans = l = 4 feet

Breadth of trash cans =  b = 4 feet

Height of trash cans =  h = 30 inches = 2.5 feet

1 inches = 0.0833333 feet

Capacity of trash can = Volume of the rectangular trash can = V

V = l × b × h

[tex]V=4 feet\times 4 feet \times  2.5 feet= 40 feet^3[/tex]

a) [tex]1 feet^3=7.48052 gallons[/tex]

[tex]V=40 feet^3=40\times 7.48052 gallons=299.221 gallons[/tex]

b) Density of water at 4°C = 1 kg /L

1 metric tonne of water = 264.17 gallons of water

[tex]V=299.221 gallons=\frac{299.221}{264.17}[/tex] metric tonne of water

[tex]V=1.1327[/tex]  metric tonne of water

Answer: The [tex]\Delta S^o[/tex] of the reaction is [tex]-579JK^{-1}[/tex]

Explanation:

Entropy change of the reaction is defined as the difference between the total entropy change of the products and the total entropy change of the reactants.

The equation representing entropy change of the reaction follows:

[tex]\Delta S_{rxn}=\sum [n\times \Delta S^o_{products}]-\sum [n\times \Delta S^o_{reactants}][/tex]

For the given chemical equation:

[tex]4NH_3(g)+3O_2(g)\rightarrow 2N_2(g)+6H_2O(l)[/tex]

We are given:

[tex]\Delta S^o_{NH_3}=192Jmol^{-1}K^{-1}\\\Delta S^o_{O_2}=205.1Jmol^{-1}K^{-1}\\\Delta S^o_{N_2}=192Jmol^{-1}K^{-1}\\\Delta S^o_{H_2O}=70Jmol^{-1}K^{-1}[/tex]

Putting values in above equation, we get:

[tex]\Delta S^o_{rxn}=[(6\times \Delta S^o_{H_2O})+(2\times \Delta S^o_{N_2})]-[(4\times \Delta S^o_{NH_3})+(3\times \Delta S^o_{O_2})][/tex]

[tex]\Delta S^o_{rxn}=[(6\times 70)+(2\times 192)]-[(4\times 192)+(3\times 205.1)]=-579JK^{-1}[/tex]

Hence, the [tex]\Delta S^o[/tex] of the reaction is [tex]-579JK^{-1}[/tex]

Explanation:

At low temperatures (below the glass transition temperature) crystalline polymers are rigid like glass. This happens because all the polymer chains are perfectly arranged, all the polymer is in the crystalline form. On the other hand, when the temperature raises, upper the glass transition temperature, some polymer chains start to get loose and form some amorphous regions in between the crystalline regions of the polymer. This condition makes the polymer more flexible.

The concentration of a 0.0075 umol of zinc oxalate in a 450 mL solution is 1.67 x [tex]10^{-8[/tex] mol/L or 0.0000000167 M.

To calculate the concentration of the zinc oxalate solution, we first convert the given quantity of zinc oxalate from umol to mol.

Converting 0.0075 umol to mol gives us 0.0075 x  [tex]10^{-6[/tex]  mol, which is 7.5 x [tex]10^{-9[/tex] mol.

Molarity is defined as the number of moles of solute per liter of solution.

So, we also need to convert 450 mL to liters, giving us 0.45L.

The concentration (C) is then calculated by dividing the number of moles (n) by the volume (V) in liters.

So, the molarity of the zinc oxalate solution can be calculated as follows: C = n/V = 7.5 x  [tex]10^{-9[/tex]  mol / 0.45L which equals 1.67 x  [tex]10^{-8[/tex]  mol/L, or 0.0000000167 M.

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Answer:

[tex]Q=\frac {[Fe^{2+}]^2[Zn^{2+}]}{[Fe^{3+}]^2}[/tex]

Explanation:

The reaction quotient of an equilibrium reaction measures relative amounts of the products and the reactants present during the course of the reaction at  particular point in the time.

It is the ratio of the concentration of the products and the reactants each raised to their stoichiometric coefficients. The conecntration of the liquid and the gaseous species does not change and thus is not written in the expression.

Thus, for the reaction:

[tex]2Fe^{3+}_{(aq)}+Zn_{(s)}\rightleftharpoons 2Fe^{2+}_{(aq)}+Zn^{2+}_{(aq)}[/tex]

The expression is:

[tex]Q=\frac {[Fe^{2+}]^2[Zn^{2+}]}{[Fe^{3+}]^2}[/tex]

Answer:

Hydrogen bonding

Explanation:

As a rule of thumb, "likes dissolve like", meaning polar solutes dissolve in polar solvents and nonpolar solutes in nonpolar solvents. In this case, water is polar (dipolar moment = 1.85 Debye) dissolves methanol which is also polar (dipolar moment = 1.69 Debye). Besides being dipoles, both molecules have atoms of Hydrogen with a covalent bond to more electronegative atoms of Oxygen. When this happens, stronger dipole-dipole interactions appear known as Hydrogen bonding. There is an electrostatic attraction between H (positive charge density) and O (negative charge density).

Answer : The mass of combustion products formed are 134 lbs.

Explanation :

The balanced chemical reaction will be:

[tex]C_3H_8+5O_2\rightarrow 3CO_2+4H_2O[/tex]

Given :

Mass of [tex]C_3H_8[/tex] = 29 lbs = 13154.2 g

conversion used : 1 lbs = 453.592 g

Molar mass of [tex]C_3H_8[/tex] = 44 g/mole

First we have to calculate the moles of [tex]C_3H_8[/tex].

[tex]\text{ Moles of }C_3H_8=\frac{\text{ Mass of }C_3H_8}{\text{ Molar mass of }C_3H_8}=\frac{13154.2g}{44g/mole}=298.9moles[/tex]

Now we have to calculate the moles of [tex]CO_2[/tex] and [tex]H_2O[/tex].

From the balanced chemical reaction we conclude that,

As, 1 mole of [tex]C_3H_8[/tex] react to give 3 moles of [tex]CO_2[/tex]

So, 298.9 mole of [tex]C_3H_8[/tex] react to give [tex]298.9\times 3=896.7[/tex] moles of [tex]CO_2[/tex]

and,

As, 1 mole of [tex]C_3H_8[/tex] react to give 4 moles of [tex]H_2O[/tex]

So, 298.9 mole of [tex]C_3H_8[/tex] react to give [tex]298.9\times 4=1195.6[/tex] moles of [tex]H_2O[/tex]

Now we have to calculate the mass of [tex]CO_2[/tex] and [tex]H_2O[/tex].

Molar mass of [tex]CO_2[/tex] = 44 g/mole

Molar mass of [tex]H_2O[/tex] = 18 g/mole

[tex]\text{Mass of }CO_2=\text{Moles of }CO_2\times \text{Molar mass }CO_2[/tex]

[tex]\text{Mass of }CO_2=896.7mole\times 44g/mole=39454.8g=86.98lbs[/tex]

and,

[tex]\text{Mass of }H_2O=\text{Moles of }H_2O\times \text{Molar mass }H_2O[/tex]

[tex]\text{Mass of }H_2O=1195.6mole\times 18g/mole=21520.8g=47.44lbs[/tex]

The total mass of products = Mass of [tex]CO_2[/tex] + Mass of [tex]H_2O[/tex]

The total mass of products = 86.98 + 47.44 = 134.42 ≈ 134 lbs

Therefore, the mass of combustion products formed are 134 lbs.

Answer:

The molecular weight of the acid is 60.05 g/mol

Explanation:

Let's state the balanced chemical equation to represent the neutralization reaction:

NaOH + HAc → NaAc + H2O

where HAc is the representation of the monoprotic acid. As we can see, the relationship between the base and the acid is 1:1, that is 1 mole of NaOH reacts with 1 mole of the monoprotic acid HAc. So, let's calculate the moles of NaOH that where present in the 88.81 mL aliquot used to neutralize the acid:

1000 mL ---- 0.75 moles of NaOH

88.81 mL --- x = (88.81 mL × 0.75 moles)/1000 mL = 0.0666075 moles NaOH

As we stated before, 1 mole of NaOH will react with 1 mole of HAc, so 0.0666075 moles of NaOH will reacted with 0.0666075 moles of the acid. Having said that, because we already know the mass of the acid, we are able to determine the molecular weight of it:

0.0666075 moles of HAc ---- 4.00 g

1 mole of HAc ---- x = (1 mole × 4.00 g)/0.0666075 moles = 60.05 g/mole

Answer:

Coal is a traditionally used source of energy, there are main four types of ranks for coal. Here the rank of a coal means to a natural process called Coalification, which takes place during a plant is buried and changes to a harder, and denser material and become even more rich in carbon contents.

Anthracite is know to have the highest ranked coal, it contains highest percent of fixed carbon and lowest percent of volatile material.

Heating a carboxylic acid with a primary amine forms a secondary amide and water.

When heating a carboxylic acid with a primary amine, the organic product formed, along with water, is a secondary amide. This reaction is an example of amidation, where the carboxyl group (-COOH) of the acid reacts with the amine group (-NH2) from the primary amine, resulting in the formation of a secondary amide and a molecule of water as a by-product. The process is important in the formation of peptides and proteins, where similar reactions link amino acids together.

Answer:

D. the forward reaction will have a lower activation energy than the reverse reaction.

Explanation:

An exothermic reaction is one which is accompanied by the release of heat energy. In this case the products have a lower energy than that of the reactants.

Activation energy is the minimum amount of energy required to initial or start a chemical reaction. In exothermic reactions, the reactants are at a higher energy (relative to the products) to begin with. Hence, they would require a lower activation energy to overcome the energy barrier in order to form the products.

The correct option is D. the forward reaction will have a lower activation energy than the reverse reaction.

In an exothermic reaction, energy is released as the reaction proceeds from reactants to products. This means that the products are at a lower energy state than the reactants. The activation energy for a reaction is the minimum amount of energy that the reactants must possess for the reaction to occur. Since energy is released during the reaction, the energy level of the products is lower than that of the reactants, and consequently, the activation energy for the reverse reaction (products going back to reactants) is higher than that for the forward reaction.

 Let's analyze each option:

A. The forward reaction is slower than the reverse reaction - This statement is not necessarily true for exothermic reactions. The rate of a reaction is determined by the activation energy and the concentration of reactants, among other factors.

 B. The reaction rate will speed up with time - This statement is not generally true. The rate of a reaction can change with time depending on various factors such as the concentration of reactants, temperature, and the presence of catalysts. However, for a simple exothermic reaction, the rate may slow down over time as the concentration of reactants decreases.

 C. The collision energy of the reactants will be greater than that of the products - This statement is true for an exothermic reaction because the reactants have more energy than the products, and the excess energy is released during the reaction.

 D. The forward reaction will have a lower activation energy than the reverse reaction - This statement is correct for an exothermic reaction. The products are at a lower energy state than the reactants, so the energy barrier for the reverse reaction is higher.

 E. The activation energy will change as the reaction progresses - This statement is not accurate in a simple sense. The activation energy is a characteristic of the reaction itself and does not change as the reaction progresses. However, the presence of intermediates or changes in reaction conditions can affect the observed activation energy.

Therefore, the correct answer is D, as it accurately describes the relationship between activation energies in an exothermic reaction.

Answer:

The first solution has a final protein concentration of 0.0002 mg/ml.

To prepare the second solution, you have to take 56.25 ml of the stock solution 8 mg/ml and to add 43.75 ml of water.

Explanation:

For this kind of dilution problems is very useful the following equation:

Where Cc and Vc are the concentration and volume of the more concentrated solution respectively, whereas Cd and Vc are the concentration and volume of the diluted concentration. If you know three of these four parameters, you can calculate the missing parameter.

For the first solution, you have the volume (0.200 ml) and concentration (1 mg/ml) of the more concentrated solution, and the volume of the diluted soluted is implied (final volume= 0.2 ml + 0.8 ml= 1 ml). Then,

Cc x Vc=Cd x Vd

0.200 ml x 1 mg/ml= Cd x 1 ml

⇒ Cd= [tex]\frac{0.200 ml x 1mg/ml}{1 ml}[/tex] = 2 x 10⁻⁴ mg/ml= 0.0002 mg/ml

For the second solution, yo have the volume of the diluted solution (100 ml), the concentration of the diluted solution (4.5 mg/ml) and the concentration of the concentratesd solution (8 mg/ml). Then,

Cc x Vc= Cd x Vd

8 mg/ml x Vc= 100 ml x 4.5 mg/ml

⇒ Vc= [tex]\frac{100 ml x 4.5 mg/ml}{8 mg/ml}[/tex]= 56.25 ml

Thus, you have to take 56.25 ml of the more concentrated solution and to add the remaining volume of water to reach a final volume of 100 ml (100-56.25 ml= 43.75 ml)

Answer: This element has +2 charge on it.

Explanation:

An ion is formed when an atom looses or gains electrons.

Magnesium is the 12th element of the periodic table having electronic configuration of [tex]1s^22s^22p^63s^2[/tex]

This element will loose 2 electrons to attain stable electronic configuration and leads to the formation of a cation having formula [tex]Mg^{2+}[/tex]

Hence, this element has +2 charge on it.

Answer: The given number in scientific notation is [tex]1.044\times 10^{-7}[/tex]

Explanation:

Scientific notation is the notation where a number is expressed in the decimal form. This means that the number is always written in the power of 10 form. The numerical digit lies between 0.1.... to 9.9.....

If the decimal is shifting to right side, the power of 10 is negative and if the decimal is shifting to left side, the power of 10 is positive.

We are given:

A number having value = 0.00000010445

Converting this into scientific notation, we get:

As, the decimal is shifting to right side, the power of 10 will be negative.

[tex]\Rightarrow 0.00000010445=1.044\times 10^{-7}[/tex]

Hence, the given number in scientific notation is [tex]1.044\times 10^{-7}[/tex]

Answer:

The advantage of using building information modeling (BIM) are as follows:

1.Model based cost estimation

2. Preconstruction project visualization

3.Safe construction site

4. Improve scheduling

5.Improve coordination and clash detection

6.Reduced mitigated risk and cost

7.Improve prefabrication

8.Better collaboration and communication

9. Strong facility management

10.Improve sequencing

Answer:

The density of carbon dioxide is 1,86 g/L

Explanation:

The global reaction is:

2 HCl (aq)+ CaCO₃ (s) → CaCl₂(aq)+ H₂O(l)+ CO₂(g)

To obtain density it is necessary to obtain calcium carbonate moles -with molar mass of CaCo₃ = 100,09 g/mol- that are the same than CO₂ moles. Then, this moles must be converted to grams -CO₂ weights 44,01 g/mol- and, with the given liters (225 L) will be possible to know density, thus:

1004,0g × 95,0% = 953,8 g of CaCO₃

953,8 g of CaCO₃ ×[tex]\frac{1 mol}{100,09 g}[/tex] =

9,53 CaCO₃ moles ≡ CO₂ moles

9,53 CO₂ moles ×[tex]\frac{44,01 g}{1 mol}[/tex] = 419,4 g of CO₂

Thus, density of Carbon dioxide is:

[tex]\frac{419,4 g}{225 L}[/tex] = 1,86 g/L

I hope it helps!

Final answer:

To find the density of carbon dioxide, first calculate the mass of calcium carbonate used. Next, use the molar mass of CaCO3 to calculate the number of moles. Finally, calculate the density of CO2 using the mass and volume.

Explanation:

To find the density of carbon dioxide, we need to calculate the mass of carbon dioxide produced. From the given information, we know that a 1004.0g sample of calcium carbonate that is 95.0% pure gives 2.25L of CO2 at STP when reacted with an excess of hydrochloric acid. First, we calculate the mass of calcium carbonate used:

Mass of CaCO3 = 1004.0g * 0.95 = 954.8g

Next, we use the molar mass of CaCO3 (100.09 g/mol) to calculate the number of moles:

Moles of CaCO3 = 954.8g / 100.09 g/mol = 9.537 mol

According to the balanced chemical equation:

CaCO3 + 2HCl -> CaCl2 + CO2 + H2O

1 mole of CaCO3 produces 1 mole of CO2. Therefore, the number of moles of CO2 produced is also 9.537 mol.

Finally, we can calculate the density of CO2:

Density = Mass / Volume

Density = 9.537 mol * 44.01 g/mol / 2.25 L = 188.70 g/L

Answer:

3-D shape of molecule and adjacent carbon atoms and their orientation.

Explanation:

Stereochemistry involves study of relative spatial positioning or arrangement of atoms which form structure of the molecules.

Stereochemistry studies focuses on the stereoisomers, which are the species which have same molecular formula but the sequence of the bonded atoms is different in the 3-D space of the atoms.

Thus,

Molecule's stereochemistry tells the 3-D shape of molecule and adjacent carbon atoms and their orientation.

Stereochemistry provides information about the three-dimensional structure of a molecule, including the arrangement of atoms and their spatial orientation.

Stereochemistry is the study of the relative arrangement of atoms in molecules and their manipulation. It provides information about the three-dimensional structure of a molecule, including the arrangement of atoms and the spatial orientation of these atoms. By showing a molecule's stereochemistry, we can understand its shape, bonding patterns, and how it interacts with other molecules.

A molecule's stereochemistry can be represented using various models, such as ball-and-stick models, wedge-and-dash representations, or space-filling models. These models help visualize the three-dimensional structure of a molecule and show the arrangement of atoms in space.