The following table lists molecular weight data for a polypropylene material. Molecular Weight Range (g/mol) xi wi
8,000 - 16,000 0.07 0.03 16,000 - 24,000 0.15 0.09 24,000 - 32,000 0.26 0.21 32,000 - 40,000 0.27 0.27 40,000 - 48,000 0.18 0.28 48,000 - 56,000 0.07 0.12
Click here to access Table 14.3. Atomic weights for several elements are included in the following table: Carbon 12.01 g/mol Chlorine 35.45 g/mol Fluorine 19.00 g/mol Hydrogen 1.008 g/mol Oxygen 16.00 g/mol Nitrogen 14.01 g/mol Compute the following:
(a) the number-average molecular weight, Enter your answer for part (a) in accordance to the question statement g/mol
(b) the weight-average molecular weight, Enter your answer for part (b) in accordance to the question statement g/mol
(c) the degree of polymerization.

Answers

Answer 1

Answer:

a) the number-average molecular weight is 32,400 g/mol

b) the weight-average molecular weight is 36,320 g/mol

c) the degree of polymerization is 770

Explanation:

Given the data in the question;

Molecular                  Mean        Number      Weight      Number        Weight

weight                                                                             average         average

(g/mol)                    Mi(g/mol)         xi                wi          xiMi                  wiMi

8,000-16,000            12,000        0.07           0.03         840                360

16,000-24,000          20,000       0.15           0.09         3000              1800

24,000-32,000         28,000       0.26           0.21          7280              5880

32,000-40,000         36,000       0.27           0.27         9720               9720

40,000-48,000         44,000       0.18            0.28         7920              12320

48,000-56,000         52,000       0.07           0.12          3640              6240

∑                                                                                Mn=32,400     Mw=36,320

so;

a)  the number-average molecular weight

Mn = ∑Mixi

so from the table above; summation of Row Mixi

Mn = ∑Mixi = 32,400

Therefore, the number-average molecular weight is 32,400 g/mol

b) the weight-average molecular weight

Mw = ∑Miwi

so from the table above; summation of Row Miwi

Mw = ∑Miwi = 36,320

Therefore, the weight-average molecular weight is 36,320 g/mol

c) the degree of polymerization

the degree of polymerization of polypropylene can be determined using number-average molecular and repeat unit molecular weight.

now, for polypropylene { CH₂ = CH - CH₃ }

the repeat unit consist of 3 carbon atoms and 6 hydrogen atoms

given that;

Atomic weight of Carbon mC = 12.01 g/mol and

Atomic weight of  Hydrogen mH = 1.008 g/mol

now we find the repeat unit molecular weight of polypropylene

m = nCmC + nHmH

where n is the number of repeat of atoms

so we substitute

m = ( 3 × 12.01) + ( 6 × 1.008)

m = 36.03 + 6.048

m = 42.078 g/mol

now we calculate the degree of polymerization;

DP = Mn / m

so we substitute

DP = 32,400 / 42.078

DP = 769.9985 ≈ 770

Therefore,  the degree of polymerization is 770


Related Questions

Question 8 of 25
What is alchemy?
O A. A scientific approach to research that uses observations and
measurements to test ideas
O B. An early form of chemistry that people used to try to turn metal
into gold
O c. A belief that chemistry forms the basis of all areas of science
O D. An ancient philosophy that taught that all matter was composed
of earth, fire, water, and air
SUBMIT

Answers

Alchemy is "an early form of chemistry that people used to try to turn metal into gold".

The development of a universal cure for illness, as well as the discovery of a way to indefinitely extend life, were the goals of mediaeval chemical research and speculative philosophy.

Boyle contributed to the evolution of chemistry from alchemy. He used the experimental approach from physics and applied it to chemistry. Boyle contributed to the comparison of these two fields of knowledge by demonstrating that chemistry is just as important to study as physics.

Therefore, the correct statement will be "An early form of chemistry that people used to try to turn metal into gold".

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Question 6 of 25
When nonionizing radiation is absorbed by matter, it usually becomes which
type of energy?
A. Thermal
B. Mechanical
C. Electromagnetic
O D. Chemical

Answers

Answer:

thermal

Explanation:

a p e x

Calculate how many grams of BeCl2 are required to produce 0.52 grams of MnCl2

Answers

Answer:

65.0cp

Explanation:

How many mL of 14.5M lithium carbonate solution must be used to deliver 4.20 g of lithium ion

Answers

Answer:

. 750 M

Explanation:

PLS HELP ME WITH THIS ILL GIVE BRAINLIEST

Answers

Answer:

1 qualiative physical  

2 qualiative   chemical

3 quantitative physcial

4 quantiative chemical

5qualiative   physcial

6quatiative    chemcial

7quanatiative physcial

8 qualiative   chemical

9quatliate  physcial

How to set up the rate expressions for the following mechanism?

A → B k1
B → A k2
B+C → D k3

If the concentration of B is small compared with the concentrations of A, C, and D, the steady-state approximation may be used to derive the rate law. Derive the rate law, and show that this reaction may follow the first-order equation at high pressures and the second-order equation at low pressures.

Answers

Answer:

Explanation:

From the given information:

A → B k₁

B → A k₂

B + C → D k₃

The rate law = [tex]\dfrac{d[D]}{dt}=k_3[B][C] --- (1)[/tex]

[tex]\dfrac{d[B]}{dt}=k[A] -k_2[B] -k_3[B][C][/tex]

Using steady-state approximation;

[tex]\dfrac{d[B]}{dt}=0[/tex]

[tex]k_1[A]-k_2[B]-k_3[B][C] = 0[/tex]

[tex][B] = \dfrac{k_1[A]}{k_2+k_3[C]}[/tex]

From equation (1), we have:

[tex]\mathbf{\dfrac{d[D]}{dt}= \dfrac{k_3k_1[A][C]}{k_2+k_3[C]}}[/tex]

when the pressure is high;

k₂ << k₃[C]

[tex]\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_3[C]}= k_1A \ \ \text{first order}[/tex]

k₂ >> k₃[C]

[tex]\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_2}= \dfrac{k_1k_3}{k_2}[A][C] \ \ \text{second order}[/tex]

Calculate the number of moles of H2SO4 required to react with 0.93 moles of Al. Do not include units in your answer. Round to the tenths place or further.

Answers

Answer:

1.40 moles of H₂SO₄.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below below:

2Al + 3H₂SO₄ —> Al₂(SO₄)₃ + 3H₂

From the balanced equation above,

2 moles of Al reacted with 3 moles of H₂SO₄.

Finally, we shall determine the number of mole of H₂SO₄ required to react with

0.93 moles of Al. This can be obtained as follow:

From the balanced equation above,

2 moles of Al reacted with 3 moles of H₂SO₄.

Therefore, 0.93 moles of Al will react with = (0.93 × 3)/2 = 1.40 moles of H₂SO₄.

Thus, 1.40 moles of H₂SO₄ is needed for the reaction.

forms of energy reflection

Answers

Answer:

any of these

Explanation:

kinetic energy: kinetic is motion, or released energy

Potential energy: porential energy is the energy of position or stored energy.

Thermal energy: is heat energy, it is stored energy that creats heat.

3. Noble gases are sometimes called "inert gases." What can you infer about the meaning of the word "inert" in chemistry?

Answers

Answer:

Noble gases are sometimes called "inert gases." What can you infer about the meaning of the word "inert" in chemistry? It refers to substances that easily lose electrons. It refers to substances that do not react with other substances. It refers to substances that have strong electrochemical charges.

Explanation:

Perform the following
mathematical operation, and
report the answer to the
appropriate number of
significant figures.
653.12 + 12.10247 = [?

Answers

Answer:

665.22

Explanation:

you see wich numbers after the decimal points have the least numbers, the one with the least u have to round your answer to that

After performing the required mathematical operation (addition), the answer is equal to 665.22.

What are significant figures?

In Mathematics, significant figures can be defined as the number of single digits or numerical values in the coefficient of a mathematical expression that are important and meaningful.

Since "653.12" has two (2) significant figures, we must ensure that 12.10247 also has two (2) significant figures as follows:

12.10247 to 2 S.F = 12.10.

Next, we would perform the required mathematical operation (addition):

653.12 + 12.10 = 665.22.

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Ethical Behavior Worksheet Situation 1. You are taking a very difficult chemistry course, which you must pass to maintain your scholarship and to avoid damaging your application for graduate school. Chemistry is not your strong suit, and, because of a just-below-failing average in the course, you will have to receive a grade of 90 or better on the final exam, which is two days away. A janitor, who is aware of your plight, informs you that he found the master for the chemistry final in a trash barrel and has saved it. He will make it available to you for a price, which is high but which you could afford. What would you do?

Answers

Answer:

I would not accept it.

Explanation:

Although it is tempting to accept the janitor's offer and save the scholarship, which is not easy to get, I would not accept his offer, as I do not believe in victories based on dishonesty and would be heavy on conscience if I did the opposite. Obviously, I would not like to lose my scholarship and for that reason, I would look for other ways that would be honest and help me improve my grade. If I could not improve and lose the scholarship, I would be extremely sad, but I would be at peace with my conscience.

Why do you think the reaction between tetraphenylcyclopentadienone and dimethyl acetylenedicarboxylate can be conducted at relatively lower temperature compared to the reaction between tetraphenylcyclopentadienone and diphenylacetylene?

Answers

Answer:

See explanation

Explanation:

The reaction between tetraphenylcyclopentadienone and dimethyl acetylenedicarboxylate as well as the reaction of  tetraphenylcyclopentadienone and diphenylacetylene are  Diels Alder reactions. The former is performed in presence of a solvent while the former is performed neat.

The reaction of tetraphenylcyclopentadienone and dimethyl acetylenedicarboxylate leads to the formation of a more resonance-stabilized aromatic ring(lower energy product) compared to the reaction of  tetraphenylcyclopentadienone and diphenylacetylene.

Hence, the reaction between tetraphenylcyclopentadienone and dimethyl acetylenedicarboxylate can be conducted at relatively lower temperature compared to the reaction between tetraphenylcyclopentadienone and diphenylacetylene.

What is the difference between an introduced species and an invasive species?

Answers

Answer and Explanation:

The introduced species is, literally, a species that was introduced into an environment by human action. In other words, an introduced species is one that is not native to a region, does not occur naturally, but has been taken by humans to that region.

An invasive species, on the other hand, is one that was introduced naturally in an environment, but multiplied in a harmful way, causing a strong imbalance in the region.

Explain why the phosphorolytic cleavage of glycogen is more energetically advantageous than its hydrolytic cleavage.

Answers

Answer:

See explanation

Explanation:

Basically, phosphorolysis involves the cleavage of a bond by adding phosphoric acid across the bond, while hydrolysis involves the cleavage of a bond by adding water across the bond.

The phosphorolytic cleavage of glycogen is energetically advantageous because the released sugar is already phosphorylated. In contrast, a hydrolytic cleavage would yield glucose, which would then have to be phosphorylated at the expense of the hydrolysis of a molecule of ATP to enter the glycolytic pathway(Biochemistry, 5th ed, Jeremy M Berg et al, 2002).

Rank the following compounds in order of increasing stability, putting the least stable first. Group of answer choices II < I < III I < II < III III < II < I III < I < II

Answers

Hello. You forgot and show the compounds. The compounds are in the attached image.

Answer:

I < II < III

Explanation:

The stability of the presented compounds must be analyzed, taking into account the free electrons to form arrangements between the atoms. In this case, the molecules of greater stability follow the concept of valence and are characterized as those that manage to reach a large number of elements that manage to obey the octet rule.

Ammonia reacts with oxygen to form nitrogen dioxide and water according to the
following equation:
4NH71875) + 70212) ---> 4NO2/2) + 6H2013)
You react ammonia and oxygen, and at the end of the experiment you find that you
produced 23 g of water and have 8.52 g of ammonia left over. Determine the mass of
oxygen reacted.
17.66 g 02
40.85 g 02
O 47.66 g 02
71.49 g 02
35.02 g 02
B

Answers

I think 02 83.92 pretty sure

What is the electrostatic potential energy (Eel) of the ionic bond between a Ca2+ ion and a S2– ion in joules? Before you do the calculation, predict whether the result you get will be less than (more negative) or greater than (less negative) than the Eel value for KCl. The ionic radii of Ca2+ and of S2– are 100 pm and 184 pm, respectively.

Answers

Answer: the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

Explanation:

Given the data in the question;

I think the value of electrostatic potential energy of calcium sulfide CaS formed will be less(more negative) than KCl because the Ca2+ and S2- ions has more charge that is +2 and -2 respectively when compared to Kcl which has +1 and -1 charge.so it will be more negative.

radius = r[tex]_{ca+2}[/tex] + r[tex]_{s-2}[/tex] = 100 + 184 = 284 pm = 2.84 × 10⁻¹⁰ m

we know that; k = 2.31 × 10⁻²⁸ J

q1 = 2  ( charge on Ca⁺² )

q2 = -2( charge on S⁻²)

so

Ep = k × q1q2/r

so we substitute

Ep = 2.31 × 10⁻²⁸ × (+2×-2) / 2.84 × 10⁻¹⁰

Ep = (2.31 × 10⁻²⁸ × -4) / 2.84 × 10⁻¹⁰

Ep = -9.24 × 10⁻²⁸ / 2.84 × 10⁻¹⁰

Ep = -3.26 × 10⁻¹⁸ J

Therefore, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

Based on the data provided, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

What is electrostatic potential energy?

The electrostatic potential energy is the work done in moving the charge from infinity to that point against the electric field.

The electrostatic potential energy between any two charges q1, q2 separated by distance r is derived from Coulomb’s law and mathematically given as:

E = k × [q1q2/r2]

where

k is a constant = 2.31 × 10⁻²⁸ Jq1 and q2 are the chargesr is the distance of separation

From the data provided:

ionic radii of Ca2+ r1 = 100 pm

ionic radii of S2– = 184 pm.

Chargeon Ca2+ = +2

Charge on S2_ = -2

From the data above, it most likely that the value of electrostatic potential energy of calcium sulfide CaS formed will be less(more negative) than KCl because the Ca2+ and S2- ions has a greater charge of +2 and -2 respectively compared to Kcl which has +1 and -1 charge.

Calculating the electrostatic potential energy, Ep:

radius = r1 + r2 = 100 + 184 = 284 pm

r = 2.84 × 10⁻¹⁰ m

k = 2.31 × 10⁻²⁸ J

q1 = 2  ( charge on Ca⁺² )

q2 = -2( charge on S⁻²)

Then:

Ep = k × q1q2/r

Substituting the values above in the equation:

Ep = 2.31 × 10⁻²⁸ × (+2 ×-2) / 2.84 × 10⁻¹⁰

Ep = (2.31 × 10⁻²⁸ × -4) / 2.84 × 10⁻¹⁰

Ep = -9.24 × 10⁻²⁸ / 2.84 × 10⁻¹⁰

Ep = -3.26 × 10⁻¹⁸ J

Therefore, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J.

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How many moles in 2.33E25 molecules of NO?
0.0258 mol
3.87E20 mol
38.7 mol
2.58E48 mol
please show work ​

Answers

Answer:

0.0258 mol Answer .......

Using the van der Waals equation, determine the pressure exerted by 4.30 mol Ar in 3.6 L at 325K.

Answers

Answer:

37.7 atm

Explanation:

Using the relation;

(P + an^2/V^2) (V - nb) = nRT

(P + an^2/V^2) = nRT/(V - nb)

a = 0.0341 atm dm^2 Mol^2

b = 0.0237 dm/mol

P = nRT/(V - nb) - an^2/V^2

P = [4.3 * 0.082 * 325 / (3.6 - (4.3 * 0.0237))] - (0.0341 * (4.3^2))/(3.6^2)

P = 114.595/(3.498) - 0.0487

P = 37.7 atm

What is the molarity of a solution that contains 78.5 g of copper(II) chloride in 1.50 L of solution?

Answers

Answer:

0.389 M

Explanation:

From the question given above, the following data were obtained:

Mass of CuCl₂ = 78.5 g

Volume of solution = 1.50 L

Molarity of CuCl₂ =?

Next, we shall determine number of mole in 78.5 g of CuCl₂. This can be obtained as follow:

Molar mass of CuCl₂ = 63.5 + (35.5×2)

= 63.5 + 71

= 134.5 g/mol

Mass of CuCl₂ = 78.5 g

Number of mole of CuCl₂ =?

Mole = mass / Molar mass

Number of mole of CuCl₂ = 78.5 / 134.5

Number of mole of CuCl₂ = 0.584 mole

Finally, we shall determine the molarity of the solution. This can be obtained as follow:

Number of mole of CuCl₂ = 0.584 mole

Volume of solution = 1.50 L

Molarity of CuCl₂ =?

Molarity = mole / Volume

Molarity of CuCl₂ = 0.584 / 1.50

Molarity of CuCl₂ = 0.389 M

The molarity of a solution that contains 78.5 g of copper(II) chloride in 1.50 L of solution is 0.389M.

HOW TO CALCULATE MOLARITY?

The molarity of a solution can be calculated

From the question given above, the following data were obtained:

Mass of CuCl₂ = 78.5 gVolume of solution = 1.50 LMolarity of CuCl₂ =?

Next, we shall determine number of moles in 78.5g of CuCl₂. This can be obtained as follow:

Molar mass of CuCl₂ = 63.5 + (35.5×2)

= 63.5 + 71

= 134.5 g/mol

Mass of CuCl₂ = 78.5g

Number of mole of CuCl₂ = 78.5 / 134.5

Number of mole of CuCl₂ = 0.584 moles

The determine the molarity of the solution. This can be obtained as follow:

Number of moles of CuCl₂ = 0.584 molesVolume of solution = 1.50LMolarity of CuCl₂ =?

Molarity = mole / Volume

Molarity of CuCl₂ = 0.584 / 1.50

Molarity of CuCl₂ = 0.389M

Therefore, molarity of a solution that contains 78.5 g of copper(II) chloride in 1.50 L of solution is 0.389M.

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Hydroxylamine hydrochloride is a powerful reducing agent which is used as a polymerization catalyst. It contains 5.80 mass % H, 20.16 mass % N, 23.02 mass % O, and 51.02 mass % Cl. What is its empirical formula? Determine the molecular formula of the compound with molar mass of 278 g.

Answers

Answer: The molecular formula will be [tex]H_{16}NOCl[/tex]

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of H = 5.80 g

Mass of N = 20.16 g

Mass of O = 23.02 g

Mass of Cl = 51.02 g

Step 1 : convert given masses into moles.

Moles of H =[tex]\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{5.80g}{1g/mole}=5.80moles[/tex]

Moles of N =[tex]\frac{\text{ given mass of N}}{\text{ molar mass of N}}= \frac{20.16g}{14g/mole}=1.44moles[/tex]

Moles of O =[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{23.02g}{16g/mole}=1.44moles[/tex]

Moles of Cl =[tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{51.02g}{35.5g/mole}=1.44moles[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For H = [tex]\frac{5.80}{1.44}=4[/tex]

For N = [tex]\frac{1.44}{1.44}=1[/tex]

For O = [tex]\frac{1.44}{1.44}=1[/tex]

For Cl = [tex]\frac{1.44}{1.44}=1[/tex]

The ratio of H: N: O: Cl= 4: 1: 1: 1

Hence the empirical formula is [tex]H_4NOCl[/tex]

The empirical weight of [tex]H_4NOCl[/tex] = 4(1)+1(14)+ 1(16) + 1(35.5)= 69.5 g.

The molecular weight = 278 g/mole

Now we have to calculate the molecular formula.

[tex]n=\frac{\text{Molecular weight }}{\text{Equivalent weight}}=\frac{278}{69.5}=4[/tex]

The molecular formula will be=[tex]4\times H_4NOCl=H_{16}NOCl[/tex]

What a main difference between Earth and Jupiter?

A. Earth is an inner planet with a solid rock surface composition, while Jupiter is an outer planet with a gas surface composition.

B. Earth is an inner planet with a relatively long distance from the sun, while Jupiter is an outer planet with a relatively short distance from the sun.

C. Earth is an outer planet with a gas surface composition, while Jupiter is an inner planet with a solid rock surface composition.

D. Earth is an outer planet with a relatively short distance from the sun, while Jupiter is an inner planet with a long distance from the sun.

Answers

Answer: A. Earth is an inner planet with a solid rock surface composition, while Jupiter is an outer planet with a gas surface composition.

Answer: What a main difference between Earth and Jupiter?

Earth is an inner planet with a solid rock surface composition, while Jupiter is an outer planet with a gas surface composition.

Earth is an inner planet with a relatively long distance from the sun, while Jupiter is an outer planet with a relatively short distance from the sun.

Earth is an outer planet with a gas surface composition, while Jupiter is an inner planet with a solid rock surface composition.

Earth is an outer planet with a relatively short distance from the sun, while Jupiter is an inner planet with a long distance from the sun.

Explanation:

Consider the reaction 2H2(g)+O2(g)→2H2O(l) 2 H 2 ( g ) + O 2 ( g ) → 2 H 2 O ( l ) What is the mass of water, H2O(l) H 2 O ( l ) , produced when 5.70 g g of O2(g) O 2 ( g ) reacts with excess H2(g) H 2 ( g ) ?hen 5.70 g g of O2(g) O 2 ( g ) reacts with excess H2(g) H 2 ( g ) ?

Answers

Answer:

mH₂O = 6.4116 g

Explanation:

Let's write the given reaction:

2H₂ + O₂ -------> 2H₂O

The problem states that 5.7 g of oxygen reacts with excess hydrogen, hence, the limiting reagent is the oxygen. With this mass of oxygen, we can determine the moles, and then, the moles of water with the mole ratio:

moles = mass / atomic weight        AW of O₂ = 16 g/mol

Replacing we have:

moles O₂ = 5.70 / (16 * 2)

moles O₂ = 0.1781 moles

According to the balanced reaction, 1 mole of Oxygen produces 2 moles of water, so we have a mole ratio 1:2, therefore the moles of water would be twice the moles of oxygen:

moles H₂O = 0.1781 * 2 = 0.3562 moles

Finally the mass of water can be calculated solving for the mass from the expression of moles, and using molecular mass of water:

m = moles * MM          MM H₂O = 18 g/mol

m = 0.3562 * 18

mH₂O = 6.4116 g

Hope this helps

how many grams of na2co3 would be needed to produce 1000g of nahco3

Answers

Answer:

630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃

Explanation:

The balanced reaction is:

Na₂CO₃ + CO₂+ H₂O → 2 NaHCO₃

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:

Na₂CO₃: 1 moles CO₂: 1 moleH₂O: 1 mole NaHCO₃: 2 moles

Being the molar mass:

Na₂CO₃: 106 g/moleCO₂: 44 g/moleH₂O: 18 g/moleNaHCO₃: 84 g/mole

Then by stoichiometry the following quantities of mass participate in the reaction:

Na₂CO₃: 1 mole* 106 g/mole= 106 gCO₂: 1 mole* 44 g/mole= 44 gH₂O: 1 mole* 18 g/mole= 18 gNaHCO₃: 2 moles* 84 g/mole= 168 g

You can apply the following rule of three: if 106 grams of Na₂CO₃ are needed to produce 168 grams of NaHCO₃, how much mass of Na₂CO₃ is necessary to produce 1000 grams of NaHCO₃?

[tex]mass of Na_{2} CO_{3}=\frac{1000grams ofNaHCO_{3} *106gramsofNa_{2} CO_{3} }{168grams ofNaHCO_{3}}[/tex]

mass of Na₂CO₃= 630.95 grams

630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃

Skin color variations were caused by:

a). The change in melanin, the skin's brown pigment

b). The climate of where people migrated to

c)Diets that are rich in Vitamin D

d) All of the above

Answers

I'm certain the answer is D: All of the above, but please correct me if I'm wrong ^^

Please balance the equation, putting the correct coefficient in each box.

Do not leave any boxes blank! Enter "1" for formulas having a presumed

coefficient of 1.

Bi(OH)3 +

HNO3 →

H2O +

Bi(NO3)3

Answers

Answer: [tex]Bi(OH)_3+3HNO_3\rightarrow 3H_2O+Bi(NO_3)_3[/tex]

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The balanced equation will be:

[tex]Bi(OH)_3+3HNO_3\rightarrow 3H_2O+Bi(NO_3)_3[/tex]

What is the concentration of a Kl solution of 20.68 g of solute was dissolved in enough water to form 100. ml of solution?

Answers

Answer:

1.25M

Explanation:

What is the major organic product obtained from the reaction of 2,2-dimethyl-1-propanol aqueous HBr at reflux

Answers

Answer:

See explanation

Explanation:

The mechanism involves SN1 nucleophilic substitution reaction. The -OH group of the alcohol is first protonated. Since water is a good leaving group, -OH2 leaves the substrate creating a primary carbo cation.

A 1,2 methyl shift now occurs to create a tertiary carbo cation which is more stable leading to the major product shown in the image attached to this answer.

Which word best describes the relationship between polyps and algae
exoskeletal
Bleached
Photosynthetic
Symbiotic

Answers

Answer:

symbiotic

Explanation:

There like a close friendship

A) Suppose you separate a 3.02 g mixture of sand and salt. You recover 1.43 g of salt and 1.41 g of sand. What is the percent recovery of the mixture?
B) Suppose you separate a 3.02 g mixture of sand and salt. You recover 1.43 g of salt and 1.41 g of sand. What is the percent recovery of the mixture?
C) Calculate the percent by mass of a solution made from 15 g NaCl (the solute) and 69 g water.
D) What percent of 73.0 g is 26.1 g?

Answers

Answer:

A-B) 94 %.

C) 17.9 %.

D) 35.8 %.

Explanation:

Hello!

A-B) In this case, since the total mass of the mixture is 3.02 g and 1.43g+1.41g=2.84 g are recovered in total, we can compute the percent recovery as shown below:

[tex]\%rec=\frac{2.84g}{3.02g}*100\%\\\\\%rec=94\%[/tex]

C) Here, since the solution is made up of NaCl and water, we can say that the mass of the solution is 15g+69g=84g; thus, the percent by mass would be:

[tex]\%=\frac{15g}{84g}*100\%\\\\\%=17.9\%[/tex]

D) In this case, we simply divide 26.1 g by 73.0 g in order to obtain the percent:

[tex]\%=\frac{26.1g}{73.0g}*100\%\\\\\%=35.8\%[/tex]

Best regards!

The percentage in the cases are as follows;

A and B is; 94%C is; 17.9%D is; 35.8%

Questions A and B are similar and can be solved as follows;

The total mass of the mixture is 3.02g.The recovered mass = 1.43g + 1.41g = 2.84g

% recovery = (2.84/3.02) × 100%

% recovery = 94%

Question C can be solved as follows;

Total mass of solution = 15 + 69 = 84gMass of solute = 15g

% by mass = (15/84) × 100%

% by mass = 17.9%

Question D can be solved as follows;

% = (26.1/73) × 100%% = 35.8%

Read more:

https://brainly.com/question/24712879

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