Element T exists as three isotopes: T-12 (98.90%), T-13 (1.00%) and T-14 (0.10%). Calculate the
average atomic mass of the element T.
Answer choices:
- 12.01 amu
- 11.72 amu
- 1200 amu
- 13 amu

Answers

Answer 1

Answer:

-10.00amu

ok.......... !!!!!

Answer 2

The average atomic mass of the element T is 12.012 amu.

What is average atomic mass?

The average atomic mass is defined as the atoms' weighted average mass in a naturally occurring sample of the element.

It is also defined as the average atomic mass of all naturally occurring isotopes of all elements.

The average atomic mass  can be expressed as

Average atomic mass = f1m1 + f2m2 + f3m3

                                    = 0.989 x 12 + 0.01 x 13 + 0.001 x 14

                                    = 11.868 + 0.13 + 0.014

                                    = 12.012 amu

Thus, the average atomic mass of the element T is 12.012 amu.

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Related Questions

Sample of carbonate rock is a mixture of CaCO3 and MgCO3. The rock is Analyzed in a laboratory and the results are recorded in the table above. Which columns in a table provide all the information necessary to determine the mole ratio of analyzed in a laboratory and the results are recorded in the table above. Which columns in a table provide all the information necessary to determine the mole ratio of Ca to Mg in the rock

Answers

Answer:

You need the mass of Mg and Ca in the sample and their molar masses

Explanation:

Its the only answer that made sense because using those 4, can give you their ration

The Columns in the table that provides the information necessary for the calculating the mole ratio of Ca to Mg are columns ; 3, 4, 6, and 7

Although some data related to your question is missing attached below is the missing data

Determining the mole ratio of Ca to Mg

           Ca         :        Mg

mass of Ca / molar mass  :  mass of Mg / Molar mass

( 36.1 / 40.1 )  :  ( 2.4 / 24.3 )

9.14  : 1

∴ The mole ratio of Mg to Ca

≈  1 : 9

Where: Column 3 = Mass of Mg in the sample ( g )

            Column 4 = mass of Ca in the sample  ( g )

             Column 6 = Molar mass of Mg ( g/mol )

             Column 7 = molar mass of Ca ( g/mol )

Hence the Mole ratio of Mg to Ca = 1 : 9

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The solubility of sugar at 50°C is 260/100g water,and at 0°Cis 180g/100g water. What mass of sugar,will be deposited if 60g the saturated solution at 50°C is cooled to 0°C​

Answers

Explanation:

27 °0 bc that how it is so this is the answer

A beaker can hold 200 cm3 of water. When it's empty, how
many liters are needed to refill it?
L

Answers

Answer:

[tex]V=0.200L[/tex]

Explanation:

Hello,

In this case, since the volumetric capacity of the beaker is 200 cm³, by considering that 1000 cm³ equals 1 L, the liters are then computed via the following unit conversion:

[tex]V=200cm^3*\frac{1L}{1000cm^3}\\ \\V=0.200L[/tex]

Best regards.

The vapor pressure of carbon disulfide is 355.6 torr at 25°C. What is the vapor pressure of a solution prepared by dissolving 10.60 g naphthalene (C10H8, Molar Mass = 128.2 g/mol) in 155 mL CS2 liquid (Molar Mass = 76.14 g/mol, density = 1.261 g/mL)? Assume the solution obeys Raoult's law, and treat naphthalene as a nonvolatile solute.

Answers

Answer:

344.5764 torr

Explanation:

Molar mass of naphthalene = 128.2g/mol

Mass of naphthalene = 10.60 g

Carbon disulfide:

Molar mass= 76.14g/mol ;

volume = 155mL ;

density = 1.261 g/mL

Vapour pressure = 355.6 torr

Number of moles = mass / molar mass

CS2:

Mass = density × volume

Number of moles = (density × volume) / molar mass

Number of moles = (1.261 * 155) / 76.14 = (195.455 / 76.14) = 2.567 moles of CS2

Number of moles of C8H10:

Number of moles = 10.60 / 128.2 = 0.083 C8H10

Total number of moles :

2.567 + 0.083 = 2.65 moles

Mole fraction of each compound in solution :

CS2 :

2.567 / 2.65 = 0.969

C8H10:

0.083 / 2.65 = 0.031

According to Raoult's:

Psolution = Xsolvent × Posolvent

CS2 = solvent

Xsolvent = Mole fraction of solvent

Posolvent = Vapour pressure of pure solvent

Psolution = 0.969 × 355.6 torr = 344.5764 torr

The vapor pressure of the solution would be as follows:

[tex]344.5764[/tex] torr

Given that,

Vapor pressure of Carbon Disulfide [tex]= 355.6[/tex] torr

[tex]volume = 155mL ;[/tex]

[tex]density = 1.261 g/mL[/tex]

Naphthalene's mass [tex]= 10.60 g[/tex]

Naphthalene's molar mass [tex]= 128.2g/mol[/tex]

Now,

We know that

Number of moles [tex]= mass/molar mass[/tex]

Mass [tex]= density[/tex] × [tex]volume[/tex]

[tex]Number of moles =[/tex] [tex](density[/tex] × [tex]volume) / molar mass[/tex]

So,

Number of moles of Carbon Disulfide [tex]= (1.261[/tex] × [tex]155) / 76.14[/tex]

[tex]= (195.455 / 76.14)[/tex]

[tex]= 2.567[/tex] moles of Carbon Disulfide

Number of moles of Naphthalene:

Number of moles [tex]= 10.60 / 128.2[/tex]

[tex]= 0.083[/tex]

Now,

Total number of moles :

[tex]2.567 + 0.083[/tex]

[tex]= 2.65[/tex] moles

Mole fraction of each compound in solution :

Carbon Disulfide:

2.567 / 2.65

[tex]= 0.969[/tex]

Naphthalene

0.083 / 2.65

[tex]= 0.031[/tex]

According to Raoult's:

P[tex]solution = Xsolvent[/tex] × [tex]Posolvent[/tex]

Carbon Sulfide = Solvent

[tex]Xsolvent =[/tex] Mole fraction of solvent

[tex]Posolvent =[/tex] Vapour  pressure of the pure solvent

[tex]Psolution[/tex] [tex]= 0.969[/tex] × [tex]355.6 torr[/tex]

[tex]= 344.5764[/tex] torr

Thus, "[tex]344.5764[/tex] torr" is the correct answer.

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Draw an important resonance form to show the delocalization of charge in the ion shown below.

Interactive 3D display mode

Answers

Answer:

Hello attached below is the missing ion diagram

Explanation:

Attached below is an important resonance form that shows the delocalization of charge in the ion shown


15.0 g of water is heated from 5 °C up to 37 °C. How much energy is absorbed by
the water? (The specific heat of liquid water is 4.184 J/g °C.)

Answers

Answer:

See the answer

1) 15.0 g of water is heated from 5 °C up to 37 °C. How much energy is absorbed by the water? (The specific heat of liquid water is 4.184 J/g°C.)

2)How many joules of energy is required to bring a five-pound (1 pound = 454 g) bag of ice from its freezer temperature at -20.0°C up to 0°C? The specific heat of ice is 2.10 J/g×°C.

3) A 50.0 mg tissue sample is taken from a patient for diagnosis. While waiting for testing, the sample is stored in a -80.0°C freezer. How much energy is released when the sample is cooled from 20.0°C down to the freezer temperature? You may assume the specific heat of the tissue sample is 3.47 J/g×K.

Bismuth oxide reacts with carbon to form bismuth metal: Bi2O3(s) + 3C(s) → 2Bi(s) + 3CO(g) When 775 g of Bi2O3 reacts with excess carbon, (a) how many moles of Bi form? mol Bi (b) how many grams of CO form? g CO

Answers

Answer:

(a) 3.33 mol Bi

(b) 140. g CO

Explanation:

Step 1: Convert 775g to moles

Bi Molar Mass - 208.98 g/mol × 2 = 417.98 g/mol

O Molar Mass - 16.00 g/mol × 3 = 48.00 g/mol

775g Bi₂O₃ ÷ 465.98 g/mol = 1.66316 mol Bi₂O₃

Step 2: Find the conversion from Bi₂O₃ to Bi

1 mole of Bi₂O₃ equals 2 moles of Bi

Step 3: Use Dimensional Analysis

1.66316 mol  ·  [tex]\frac{2 \hspace{2} mol \hspace{2} Bi}{1 \hspace{2} mol \hspace{2} Bi_2O_3}[/tex] = 3.32632 mol Bi

3.32632 mol Bi ≈ 3.33 mol Bi (3 significant figures)

Step 4: Find the conversion from Bi₂O₃ to CO

1 mole of Bi₂O₃ equals 3 moles of CO

Step 5: Use Dimensional Analysis

1.66316 mol  · [tex]\frac{3 \hspace{2} mol \hspace{2} CO}{1 \hspace{2} mol \hspace{2} Bi_2O_3}[/tex] = 4.98948 mol CO

Step 6: Find molar mass of CO and convert moles to grams

C - 12.01 g/mol

O - 16.00 g/mol

4.98948 mol CO · 28.01 g/mol = 139.775 g CO

139.775 g CO ≈ 140. g CO (3 significant figures)

What is a single covalent bond?

Answers

Answer: Single Covalent Bonds

Hydrogen and chlorine coming together is an example of a single covalent bond. Two hydrogen atoms will also come together to form a single covalent bond, as will two chlorine atoms. In these examples, each individual atom has just one unpaired electron to share with the other atom.

A Little Backstory I Guess: In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.

sorry its so long :/ hope this even relatively helps...

You have two compounds that you have spotted on the TLC plate. One compound is more polar than the other. You ran the TLC plate with neat hexanes and found that only one spot moved a small distance up the plate. What might you expect to see if you ran a TLC plate in a 50/50 mixture of hexanes and ethyl acetate

Answers

Answer:

we will except an increase in the polarity of the system and this will cause the Non-polar spot to be near the solvent front, while the polar spot will run at an approximate speed of 0.5 Rf

Explanation:

when we run a TLC plate in a 50/50 mixture of hexanes and ethyl acetate we will except an increase in the polarity of the system and this will cause the Non-polar spot to be near the solvent front, while the polar spot will run at an approximate speed of 0.5 Rf

The speed of the polar spot depends largely on the level of polarity, an increase in the polarity will see both spots of Neat hexane run when we run a TLC  plate in a 50/50 mixture of hexanes and ethyl acetate

Which set of elements has 4 valence electrons?

Answers

Answer:

carbon group

All the carbon group atoms, having four valence electrons, form covalent bonds with nonmetal atoms; carbon and silicon cannot lose or gain electrons to form free ions, whereas germanium, tin, and lead do form metallic ions but only with two positive charges.

The set of elements that has 4 Valence electrons are the carbon group.

What are valence electrons?

Valence electrons are those electrons that are found at the outermost shell of an element that can go into formation of chemical bonds with another element on a chemical reaction.

The group 14 elements in the periodic table are known to have a four Valence electron on their outermost shell.

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3. Diesel fuel has a density of 0.839g/mL What is the volume, in gallons, of 2.3 kg of diesel? [1 gallon = 3.79 L)​

Answers

Answer:

0.71 gal

Explanation:

Step 1: Given data

Density of Diesel (ρ): 0.839 g/mL

Mass of Diesel (m): 2.3 kg

Step 2: Convert "m" to grams

We will use the relationship 1 kg = 10³ g.

2.3 kg × (10³g/1 kg) = 2.3 × 10³ g

Step 3: Calculate the volume (V) of the Diesel sample

We will use the density formula.

ρ = m/V

V = m/ρ

V = 2.3 × 10³ g/(0.839 g/mL)

V = 2.7 × 10³ mL

Step 4: Convert "V" to L

We will use the relationship 1 L = 10³ mL.

2.7 × 10³ mL × (1 L / 10³ mL) = 2.7 L

Step 5: Convert "V" to gal

We will use the relationship 1 gal = 3.79 L.

2.7 L × (1 gal/3.79 L) = 0.71 gal

Answer:

2.3 kg x1000 g/kg = 2300 g

2300 g x 1 ml/0.839 g = 2741 ml

2741 ml x 1 L/1000 ml = 2.741 L

2.741 L x 1 gal/3.79 L = 0.72 gallons

Explanation:

28 Which of the following equations does not represent a redox reaction?
A
B
с
D
2AgBr (s) → 2Ag (s) + Br2 (g)
Cu2+ (aq) + Zn (s) → Cu (s) + Zn2+ (aq)
2Fe (s) + 3Cl2 (9) ► 2FeCl3 (s)
MgO (s) + 2HCl (aq) → MgCl2 (aq) + H20 (1

Answers

Answer:

The answer is D. In the reactions A,B and C the reactants undergo changes in oxidation number. And also the reaction D is an acid_base neutralization reaction.

How does the number of valence electrons in atoms of metalloids explain why metalloids are semiconductors? They have one or two valence electrons, so they cannot lose electrons easily. They have one or two valence electrons, so they can lose or gain electrons. They have three to six valence electrons, so they cannot lose electrons easily. They have three to six valence electrons, so they can lose or gain electrons.

Answers

Answer:

They have three to six valence electrons, so they can lose or gain electrons.

Explanation:

Here, we are required to identify how the number of Valence electrons on atoms of metalloids explain why metalloids are semiconductors.

This is because; They have three to six valence electrons, so they can lose or gain electrons

Metalloids are elements in the periodic table which are characterized by the the presence of 3 to 6 Valence electrons.

Metalloids unlike Alkali and alkali earth metals (which have 1 and 2 Valence electrons and are highly electropositive) and halogens( with valency of 7 and are highly electronegative) have three to six valence electrons and are therefore able to lose or accept electrons.

Ultimately, the presence of three to six Valence electrons and the ability to either lose or gain electrons is the criteria for their semiconductor character.

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A non-conservative force acting on a particle:_________.
A) does work that can depend on the path of motion.
B) does work equal to the change in the kinetic energy of the particle.
C) does work that is never equal to the change in kinetic energy of the particle.
D) can not have an associated potential energy function.
E) does work that only depends on the endpoints of the path, not on the path between the endpoints.

Answers

Answer: Option A.

does work that can depend on the path of motion.

Explanation:

A non-conservative force acting on a particle does work that can depend on the path of motion because a non conservative force is a type of force that can remove energy from a progressive system and this energy cannot be restored back and the forces are path dependent because it matters where the particle begin or end.

It is a type of force such as friction or air resistance. This type of force does work that only depend on the path of motion.

If a boy was standing on his head, his mouth would be ___ to his nose.

Answers

Answer:

The correct answer is "inferior".

Explanation:

In anatomy, the term inferior is used to describe parts of the body that are below other part used as reference. Inferior comes from the Latin "inferus" that means "below". In this case, the mouth will always be inferior to the nose, it doesn't matter if the boy was standing on his head or if he is in other position.

Answer:

correct answer, inferior.

Explanation:

of little or less importance, value, or merit always felt inferior to his older brother. 2a : of low or lower degree or rank. b : of poor quality : mediocre. 3 : situated lower down : lower.

If one person is regarded as inferior to another, they are regarded as less important because they have less status or ability. He preferred the company of those who were intellectually inferior to himself.

Hope this helped!

What is the solubility product expression for Zn3(PO4)2?

Answers

Answer:

[tex]Ksp=[Zn^{2+}]^3[PO_4^{3-}]^2[/tex]

Explanation:

Hello,

In this case, since the equilibrium dissociation of zinc phosphate is:

[tex]Zn_3(PO_4)_2(s)\rightleftharpoons 3Zn^{2+}(aq)+2(PO_4)^{3-}(aq)[/tex]

Due to the fact that only the zinc and phosphate ions are in aqueous state, the solubility product expression is written considering the law of mass action in which the concentration of each species is powered to the corresponding stoichiometric coefficient as follows:

[tex]Ksp=[Zn^{2+}]^3[PO_4^{3-}]^2[/tex]

Best regards.

Chromium(III) oxide reacts with hydrogen sulfide (H2S) gas to form chromium(III) sulfide and water: Cr2O3(s) + 3H2S(g) → Cr2S3(s) + 3H2O(l) To produce 156 g of Cr2S3, (a) how many moles of Cr2O3 are required? mol (b) how many grams of Cr2O3 are required? g

Answers

Answer:

(a) 0.779 mol Cr₂O₃

(b) 118 g Cr₂O₃

Explanation:

Step 1: Convert 156 g Cr₂S₃ to moles

Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol

S Molar Mass - 32.07 g/mol × 3 = 96.21 g/mol

156 g Cr₂S₃ ÷ 200.21 g/mol = 0.779182 mol Cr₂S₃

Step 2: Find conversion from Cr₂S₃ to Cr₂O₃

1 mol Cr₂S₃ equals 1 mol Cr₂O₃

Step 3: Use Dimensional Analysis

0.779182 mol Cr₂S₃ · [tex]\frac{1 \hspace{2} mol \hspace{2} Cr_2O_3}{1 \hspace{2} mol \hspace{2} Cr_2S_3}[/tex] = 0.779182 mol Cr₂O₃

0.779182 mol Cr₂O₃ ≈ 0.779 mol Cr₂O₃ (3 significant figures)

Step 4: Convert moles to grams

Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol

O Molar Mass - 16.00 g/mol × 3 = 48.00 g/mol

0.779182 mol Cr₂O₃ · 152.00 g/mol = 118.436 g Cr₂O₃

118.436 g Cr₂O₃ ≈ 118 g Cr₂O₃ (3 significant figures)

KCl is an ionic salt with a formula weight of 74.54 g/mole. A 1.417 M (mole/liter) KCl solution has a density of 1064.5 grams/liter at 20.0 OC. Use the Molarity and the formula weight to find the mass (g) of salt in one liter. Then, find the mass (g and kg) of water in one liter of the solution as the difference between the solution mass and the KCl mass. Include the conversion factor. Determine the molality (m), or moles of salt per kg of water, by dividing the moles of salt in one liter by the kg of water in one liter. Show all units and use proper significant figures. (

Answers

Answer:

Mass of the salt:  105.6g of KCl.

Mass water: 958.9g of water.

Molality: 1.478m.

Explanation:

Mass of the salt:

In 1L, there are 1.417 moles. In grams:

1.417 moles KCl * (74.54g / mol) = 105.6g of KCl

Mass of the water:

We can determine the mass of solution (Mass of water + mass KCl) by multiplication of the voluome (1L and density 1064.5g/L), thus:

1L * (1064.5g / L) = 1064.5g - Mass solution.

Mass water = 1064.5g - 105.6g = 958.9g of water

Molality:

Moles KCl = 1.417 moles KCl.

kg Water = 958.9g = 0.9589kg.

Molality = 1.417mol / 0.9589kg = 1.478m

Observations made during an experiment are called

Answers

Observation consists of receiving knowledge of the outside world through our senses,or recording information using scientific tools and instruments.Any data recorded during an experiment can be called and observation.

A cube has an edge length of 9 cm .

If it is divided up into 1-cm cubes, how many 1-cm cubes would there be?

Answers

Answer:

9^3 i think so like 279

Explanation:

blah

Which pair of elements have chemical properties that are most similar

Answers

[tex]\text{Hello there! :)}[/tex]

Answer:

[tex]\large\boxed{(B)}[/tex]

Elements on the periodic table that are the closest in characteristics are in the same group, or column.

Looking at the answer choices, the only two pairs of elements that are in the same group are (B) Al and Ga, as well as (D) F and I.

On the periodic table, Al (Aluminum) and Ga (Gallium) are only one period (row) away from each other, while F (Flourine) and I (Iodine) are 3 periods away.

***Periods determine the number of energy levels and other properties, so elements that are closer to each other would have more similar properties.

Therefore, Aluminum and Gallium contain the most similar chemical properties.

what is formed when polyatomic ions bond with other ions.
A) ionic compounds.
B) neutral compounds.
C) ionic elements.
D) neutral elements.​

Answers

Answer:

iconic compounds is your anwser

Answer:

Iconic Compounds

Explanation:

I watched a video about it.

Have a nice Friday!

What percentage of light hits Earth’s surface directly?

3 percent
5 percent
31 percent
47 percent

Answers

Answer: yall trust me on this one, i took one for the team. The answer is "C" or you can say 31 percent. boys get me 50 thanks.

Explanation:

The percentage of sunlight that hits the Earth's surface directly is 31 percent. The correct option is C.

What is sunlight?

Sunlight is the electromagnetic radiation transferred by the sun.

The sun is 93 million away from the earth, so it takes eight and half minutes to reach the sunlight to the earth.

Only 30 to 34 percent of light reaches the earth, and the remaining lights are reflected back by clouds and the earth itself.

Thus, the correct option is C, 31 percent.

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Identify the type of chemical reaction taking place in the following and write in balanced equation from
a) Barium Chloride mixed with copper sulphate solution and a white precipitate is observed b) On heating green colour sirf ferrous sulphate crystals reddish brown solid left and smell of gas having order of burning sulphur is produced.​

Answers

Answer:

a. The balanced chemical equation is written below and this is a type of double displacement reaction.

Explanation:

When barium chloride reacts with copper sulfate, a white precipitate of barium sulfate is observed.

The chemical equation for the reaction of barium chloride and copper sulfate follows:

b.

2FeSO4--(heat)---> Fe2O3 + SO2+ SO3

This Reaction is an example of Thermal Decomposition Reaction.

3. The 2 in 1s2 represents the number of
located in that energy level.
Answers:
electrons
protons

Answers

Answer:

electrons

Explanation:

In an atom, you can have varying numbers of electrons, depending on if its an ion or not.  You can use the orbitals to see the energy level of the atom.

An atom has only one number of protons.  The number of protons cannot vary.

A. The measured pH of a 0.100 M HCl solution at 25 degrees Celsius is 1.092. From this information, calculate the activity coefficient of H+.B. The measured pH of a solution of 0.010 HCl and 0.090 KCl at 25 degree Celsius is 2.102. Calculate the activity coefficient of H+ in this solution.C. Why does the pH change in part B relative to that in part A?

Answers

Answer:

activity coefficient [tex]\mathbf{\gamma =0.809}[/tex]

activity coefficient [tex]\mathbf{\gamma = 0.791}[/tex]

The change in pH in part A = 0.092

The change in pH in part B =  0.102

Explanation:

From the given information:

pH of HCl solution = 1.092

Activity of the pH solution [a] = [tex]10^{-1.092}[/tex]

[a] = 0.0809 M

Recall that [a] = [tex]\gamma[/tex] × C

where;

[tex]\gamma[/tex]  = activity coefficient

C = concentration

Making the activity coefficient the subject of the formula, we have:

[tex]\gamma = \dfrac{[a]}{C}[/tex]

[tex]\gamma = \dfrac{0.0809 \ M}{0.100 \ M}[/tex]

[tex]\mathbf{\gamma =0.809}[/tex]

B.

The pH of a solution of HCl and KCl = 2.102

[a] = [tex]10^{-2.102}[/tex]

[a] = 0.00791 M

activity coefficient [tex]\gamma = \dfrac{0.00791 \ M}{0.01 \ M}[/tex]

[tex]\mathbf{\gamma = 0.791}[/tex]

C. The change in pH in part A = 1.091 - 1.0 = 0.092

The change in pH in part B = 2.102 -2.00 = 0.102

How many atoms are represented by one formula unit of aluminum carbonate A12(CO2)3

Answers

Answer:

well ,if I have done my sum rights there are

14 atom in the one formula unit of aluminium carbonate.

Answer:

14 atoms

Explanation:

write the number in scientific notation 1123

Answers

1.123 * 10^3 thatsssss it

what is biotic?check all that apply​

Answers

where are the answers that apply .. hopes this help :)

Answer: biotic is Living things in their ecological relations.

Explanation:

Which of these is a chemical property?

boiling point
odor
ability to rust
color

Answers

Answer:

ability to rust

Explanation:

i'm like 90% sure thats correct

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