How many hydrogen atoms are in 7.80 mol of ammonium sulfide?

Answers

Answer 1

The number  of hydrogen atoms that are in 7.80 moles of ammonium sulfide are  3.756 x 10^25  atoms


calculation

Step  1:  calculate  the  moles of H  in  (NH4)2S

 since there are 8 atoms of  H in (NH4)2S  the moles of

   H =  8 x7.80 =  62.4  mole

 Step  2: use of Avogadro's law  constant  to  determine the number  of  H atom

          that is 1 mole = 6.02 x10^23 atoms

                     62.4 moles=?  atoms

cross  multiplication

= [ 62.4  x 6.02 x10^23]/  1 mole= 3.756  x10^25    atoms

Answer 2

Answer: There are [tex]3.75 \times 10^{25}[/tex] number of H atoms in 7.80 mol of ammonium sulfide.

Explanation:

The formula of ammonium sulfide is [tex](NH_{4})_{2}S[/tex].

There are 2 nitrogen atoms, 8 hydrogen atoms and 1 sulfur atom in one molecule of ammonium sulfide.

Calculate moles of hydrogen atoms as follows.

              [tex]8 \times 7.80[/tex] = 62.4

According to Avogadro's number 1 mole contains [tex]6.022 \times 10^{23} atoms[/tex]

Therefore, calculate number of H atoms as follows.

               [tex]62.4 \times 6.022 \times 10^{23}[/tex]

             = [tex]375.77 \times 10^{23}[/tex]

             = [tex]3.75 \times 10^{25}[/tex]

Thus, there are [tex]3.75 \times 10^{25}[/tex] number of H atoms in 7.80 mol of ammonium sulfide.


Related Questions

If the frequency of an FM wave is 8.85 × 107 hertz, what is the period of the FM wave?

Answers

NAMASTE

HERE IS YOUR ANSWER:

[tex] \boxed{Frequecy = \frac{1}{time \: period} } [/tex]

Frequency (given) = 8.85× [tex] {10}^{7} [/tex]hz

time period =
[tex] \frac{1}{8.85 \times {10}^{7}} [/tex]

= 0.112 × [tex] {10}^{-7} [/tex]

= 1.12 × [tex]{10}^{-8}[/tex]

Answer: The period of the FM wave [tex]1.1299\times 10^{-8} seconds[/tex].

Explanation:

Frequency of the wave = [tex]8.85\times 10^{7} Hertz[/tex]

Frequency is inverse of time period that is :

[tex]Frequency=\frac{1}{\text{Time period}}[/tex]

[tex]\text{time period}=\frac{1}{frequency}[/tex]

[tex]=\frac{1}{8.85\times 10^{7} Hertz}=0.11299\times 10^{-7} seconds=1.1299\times 10^{-8} seconds[/tex]

The period of the FM wave [tex]1.1299\times 10^{-8} seconds[/tex].

Jena's blueberry-pineapple smoothie measured 200g and was contained in 300ml. What is it's density?

Answers

The density of Jena’s smoothie is 0.667 g/mL.

Mass = 200 g

Volume = 300 mL

Density = mass/volume = 200 g/300 mL = 0.667 g/mL

Answer:

rounded it is 0.67 g/ml

Explanation: i took the test it was a bit confusing but i figured it out

A gas at constant volume has a pressure of 4.50 atm at 200. K. What will be the pressure of the gas at 250. K?

Answers

The Ideal Gas Law allows us to assume that at constant volume the variation in pressure is proportional to the variation in temperature.

Hence,

[tex]\frac{P1}{T1} = \frac{P2}{T2}\\ \\

\frac{4.50}{200} =\frac{P2}{250} \\ \\

P2 = \frac{4.50 * 250}{200}\\ \\

P2 = 5.63 atm[/tex]

Using Gay-Lussac's Law,  we get [tex]P_2[/tex]  [tex]5.625 atm[/tex] at [tex]250 K[/tex].

To find the new pressure of a gas at constant volume when the temperature changes, we use Gay-Lussac's Law, which states that pressure is directly proportional to temperature for a given mass of gas at constant volume. The formula for Gay-Lussac's Law is:

[tex]\frac{P_1}{T_1} = \frac{P_2}{T_2}[/tex]

Where:

[tex]P_1[/tex] is the initial pressure[tex]T_1[/tex] is the initial temperature[tex]P_2[/tex] is the final pressure[tex]T_2[/tex] is the final temperature

Given:

[tex]P_1 = 4.50 \, \text{atm}[/tex]

[tex]T_1 = 200 \, \text{K}[/tex]

[tex]T_2 = 250 \, \text{K}[/tex]

Rearrange the formula to solve for [tex]P_2[/tex]:

[tex]P_2 = P_1 \times \frac{T_2}{T_1}[/tex]

Substitute the known values:

[tex]P_2 = 4.50 \, \text{atm} \times \frac{250 \, \text{K}}{200 \, \text{K}}[/tex]

Calculate:

[tex]P_2 = 4.50 \, \text{atm} \times 1.25 \\ \implies P_2= 5.625 \, \text{atm}[/tex]

The new pressure of the gas at [tex]250 K[/tex] will be [tex]5.625 atm[/tex].

What is one chemical property of iron?
A) Iron is malleable.
B) The density of iron is 7.86 g/cc.
C) Iron combines readily with oxygen.
D) Iron is a good conductor of electricity and heat.

Answers

A chemical property of iron is its ability to combine with oxygen to form iron oxide, commonly known as rust; this process is known as corrosion. Therefore, the correct answer is that iron combines readily with oxygen "C".

The question asks about the chemical property of iron. Chemical properties describe the ability of a substance to undergo a specific chemical change. For iron, a key chemical property is its capability to combine with oxygen to form iron oxide, commonly known as rust. This process is part of a broader category of chemical changes known as corrosion. Unlike physical properties, which can be observed without changing the substance, chemical properties can only be seen as the substance is transformed into a different substance. Therefore, the correct answer to the question is C) Iron combines readily with oxygen.

what is the strongest metal known to man? may mark brainliest

Answers

I'm pretty sure the strongest metal known to man is Tungsten.

What chemical element did hennig brand discover and what was he boiling down when he discovered it

Answers

Hennig Brand discovered Phosphorus while he was boiling Urine to produce gold.

What is the predicited order of first ionization energies from highest to lowest for lithium sodium potassium and rubidium

Answers

The predicted order of ionization energies is Li > Na > K > Rb

Atomic size increases as you go down a Group (see image). We are adding electrons to increasingly larger shells.

The valence electrons are further from the attraction of the nucleus, so they are less tightly held.

Thus, Li has the highest ionization energy and Rb the lowest.

Significant figures communicate the level of precision in measurements

Answers

You are right! That is true.

Classify the reactions as endothermic or exothermic....PLEASE HELP ASAP

Answers

1) Endothermic reactions:

a) The reaction between ammonium nitrate and water absorbs heat from the surrounding environment.

There are two types of reaction: endothermic reaction (chemical reaction that absorbs more energy than it releases) and exothermic reaction (chemical reaction that releases more energy than it absorbs).

b) Ammonium chloride dissolved in a beaker of water makes the beaker cold.

Dissolving this salt absorbs heat from beaker.

c) Water separates on hydrogen and oxygen when an electric current is run through it.

Electrolysis of water is the decomposition reaction (heat is required), because from one molecule (water) two molecules (hydrogen and oxygen) are produced. Water is separated into two molecules.

2) Exothermic reactions:

a) Three drops of concetrated sulfuric acid added to 100 milliliters in a beaker makes the beaker hot.

Energy is released, beaker absorbs that heat.

b) Uranium atoms are split to produce nuclear energy.

Nuclear energy is released.

c) Methane and oxygen are combined to produce methanol and heat.

Balanced chemical reaction: 2CH₄ + O₂ → 2CH₃OH + heat.

What is the formula for water

Answers

Formula for water? There is no formula, but there is a symbol, if that's what you meant. The symbol for water is H2O. It means 2 Hydrogen molecules, because the symbol is H. And the O stands for Oxygen. So it meands two hydrogen molecules bonded with one oxygen molecule. Hope I helped :)

Answer:

Explanation:

what do you mean do you mean H2O

A light wave travels at a speed of 3.0 × 108 meters/second. If the wavelength is 7.0 × 10-7 meters, what is the frequency of the wave?

Answers

c = f*L 


If you cant remember this just consider the units of each (denoted [c] is units of c): 


[c] = meters/second, [f] = 1/seconds or Hertz, [L] = meters 


So [c] = [f*L], an easy way to remember it. 


So to get the frequency, just solve for f: 


f = c/L = (3.00 x 10^8)/(5.93 x 10^-7) m/s = 5.05902192 × 10^14 m/s ~ 5.06 x 10^14 m/s 


what are the limitations of the Klmn electronic configuration style of writing

Answers

In the KLMN electronic configuration style of writing K denotes the first shell which can hold up to two electrons, L denotes the second shell which can hold up to eight (2 + 6) or 8 electrons, M denotes the third shell which can hold up to eight (2 + 6 + 10) or 18 electrons etc.

The KLMN style of writing  only indicates the number of electrons in each principal quantum number, however the spdf electronic configuration style of writing subdivides each shell into its subshells.

For instance the 3rd principal quantum number has s,p and d subshells, wherein s, p and d orbitals can have a maximum of 2, 6 and 10 electrons respectively.


WILL GIVE BRAINIEST
Listed in the Item Bank are some important labels for sections of the image below. To find out more information about labels, some have more details available when you click on them. Drag and drop each label to the corresponding area it identifies in the image.

Word Bank:

Alkali Metals
Alkaline Earth Metals
Metalloid
Metals
Noble Gas
Nonmetal
Transition Metals

Answers

To the blue column on extreme left (group-1) drag and put ALKALI METALS.

To the orange column (group-2) write down Alkaline earth metals

To the next parrot green column (from group 3 to group 12) write down transition metals.

From group 1 to 12 write metals

The yellow part is non metals

The pink last column (group 18)is noble gas

The peach colored is metalloids.

Explanation:

Elements of group 1 represented in the blue column are alkali metals.

Elements of group 2 represented in the peach column are alkaline earth metals.

Elements from scandium to zinc or all the elements represented in the green columns are transition metals.

Elements in coral pink boxes represent metalloids, that is, they show properties of both metals and non-metals.

Elements present in blue, peach, green and coral pink boxes are all metals.

Whereas elements present in pink, that is, group 18 are all noble gases.

And elements present in yellow boxes are all non-metals.

(PLEASE HELP will give first correct answer brainliest!!) Which option correctly describes glucose catabolism?

1. Glucose is broken down in glycolysis, yielding two ATP molecules; after the Krebs cycle, 34 molecules of ATP are formed in ETS reactions.

2. Glucose is broken down in glycolysis, yielding pyruvic acid; after the Krebs cycle, two molecules of ATP are formed in ETS reactions.

3. Glucose is broken down in glycolysis, yielding two ATP; after the Krebs cycle, NADH and FADH2 are formed, yielding NAD+ and FAD in ETS reactions.

4. Glucose is broken down in glycolysis, yielding pyruvic acid; after the Krebs cycle, NADH and FADH2 are formed, yielding 34 ADP in ETS reactions.

Answers

The correct answer is number 1
Th correct answer is number 1

What is the name of the compound CO?\

Answers

Carbon Monoxide is the correct answer

Carbon Monoxide would be the correct answer.

If an decrease in temperature accompanies a reaction, what occurred?

Answers

I think the correct answer from the choices listed above would be the last option. If a decrease in temperature accompanies a reaction, then energy was absorbed which means that the reaction is endothermic. Hope this answers the question. Have a nice day.


Answer:

It should be  endothermic reaction.

Explanation:

Because it absorbs more energy than release it.

I took the test before.  

You can see my other article just search in search engine with: Learningandassignments diy4pro

Click on my site and find these related article post:

Chemical Reactions Learning for quiz Unit 3 Lesson 2 Physics

Hope it helps.

#diy4pro

What process uses atomic particles and uranium to determine exact age ?

Answers

the decay of the neutrons in the nucleus of the atom

The process of radiometric dating uses the decay of uranium-238 to lead-206 to determine the age of ancient rocks.

U-238 decays to stable Pb-206 largely by the emission of α particles, with a half-life of about 4.5 × 10⁹ a.

Thus, geologists can determine the age of rocks by measuring the relative amounts of U-238 and Pb-206.

However, the method is not “exact”.

The rock must be more than ten million years old so that enough uranium can decay to make the amount of lead measurable.

The age uncertainty for 100-million-year-old rocks ranges from 100 000 a

to 3 000 000 a.

The error margin for older rocks, say, 2.5 billion years old, can be as low

as 2 000 000 a. That’s a long time, but it’s an uncertainty of less than 0.1 %.

Which of the following is a solution?
a) sand
b) salt water
c) orange juice
d) granola

Answers

I think the answer would be B) Salt water because the other options wouldn't make much sense.

How many moles of ammonia, NH3, can be made from 7.5 moles of H2? N2 + 3H2 → 2NH3 A. 15 moles B. 22 moles C. 5 moles

Answers

The reaction will produce C. 5 mol NH₃.  

N₂ + 3H₂ ⟶ 2NH₃

Moles of NH₃= 7.5 mol H₂ × (2 mol NH₃/3 mol H₂) = 5 mol NH₃

5 moles of ammonia, [tex]NH_3[/tex], can be made from 7.5 moles of [tex]H_2[/tex].

What is a mole?

The mole is an SI unit used to measure the amount of any substance. The abbreviation for a mole is mol. One mole is exactly 6.02214076×[tex]10^{23}[/tex] particles.

Given data:

Moles of H₂ react = 7.5 mol

Moles of NH₃ formed =?

Chemical equation:

N₂ + 3H₂       →    2NH₃

Now we will compare the moles of ammonia with hydrogen.

            H₂              :           NH₃

             3               :             2

            7.5             :          [tex]\frac{2 X 7.5}{3}[/tex]  = 5

Hence, 5 moles of ammonia would be formed from 7.5 moles of hydrogen.

Learn more about mole here:

https://brainly.com/question/26416088

#SPJ2

an atom of gallium has 31 proton and a mass number of 70 what is the atomic number for an atom of gallium

Answers

Hello!

Atomic Number, is the number where the atom lays on the perodic table and can be found through the number of protons. Meaning that gallium has an atomic number of 31 !

Atomic weight, which is equal to 70 in this case, can be found by subtracting the atomic number from that total to find the remaining number of neutrons that make up the mass. So gallium has 31 protons and 39 protons.


Hope this helps answer your question.

Answer: The correct answer is 31.

Explanation:

Atomic number is defined as the number of protons or electrons that are present in a neutral atom.

Atomic number = number of protons = number of electrons

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

We are given:

Number of protons = 31

Mass number = 70

Number of neutrons = Mass number - Number of protons = 70 - 31 = 39

Atomic number will be equal to the number of protons present in an atom which is 31

Hence, the correct answer is 31.

What is the pH of a 0.28 M solution of ascorbic acid

Answers

Hey there!

Values Ka1 and Ka2 :

Ka1 => 8.0*10⁻⁵

Ka2 => 1.6*10⁻¹²

H2A + H2O -------> H3O⁺  + HA⁻

 Ka2 is very less so I am not considering that dissociation.

Now Ka = 8.0*10⁻⁵ = [H3O⁺] [HA⁻] / [H2A]

lets concentration of H3O⁺  = X then above equation will be

8.0*10−5 = [x] [x] / [0.28 -x

8.0*10−5 = x² /  [0.28 -x ]

x² + 8.0*10⁻⁵x  - 2.24 * 10⁻⁵

solve the quardratic equation

X =0.004693 M

pH = -log[H⁺]

pH = - log [ 0.004693 ]

pH = 2.3285

Hope that helps!

what is the answer for this thing below? and how you've done it.
[tex]8x - 9 = 8[/tex]

Answers


[tex]8x - 9 = 8[/tex]
+9 +9 (add 9 in both sides)
[tex]8x = 17[/tex]
÷8 ÷8 (divide 8 in both sides)
[tex]x = \frac{17}{8} [/tex]
Here you go
If you don't know how I've done you need to use their inverse operations.




To solve this, first add 9 on both sides.

8x-9+9=8+9

8x=17

Then divide both sides by 8 to find the value of x.

[tex]\frac{8x}{8}[/tex]=[tex]\frac{17}{8}[/tex]

x=[tex]\frac{17}{8}[/tex]

The final answer is x=[tex]\frac{17}{8}[/tex] or 2.125.

Most of the mass of an atom is contained in its _____. A. electrons B. protons C. nucleus D. neutrons

Answers

Atom is made up of NUCLEUS and electrons revolving around nucleus.

Nucleus itself contains protons and neutrons. Protons and neutrons are approximately 1680 times heavier than the electrons. So the major contribution to the mass of an atom comes from the nucleus.

Answer is C.

What is the name for the ocean current that brings warm water from the Gulf of Mexico to Western Europe

Answers

that is called the Gulf Stream

question answered by

(jacemorris04)

I believe it’s the golf stream

Please help ASAP. I'm stuck on this one question. >.<
Which is a pure substance?
A. A mixture
B. A solution
C. a compound

Answers

C. A compound !hope this helps!

Im pretty sure the answer is C. a compound


Upon landing, the 90.7 kg carbon fiber brakes of an airliner heat up 312∘C, producing heat. As the brakes start to cool back to their initial temperature, the heat is absorbed by the 123 kg rubber tires. Assuming that all of the heat is transferred from the brakes to the tires, what is the specific heat of the tires if their temperature rises 172∘C?

Round your answer to two decimal places.
Use 1.400Jg∘C for the specific heat of carbon fiber.

Answers

The calculation results in a specific heat of approximately 1.89 J/g°C.

To calculate the specific heat of the tires we first find the amount of heat absorbed by the brakes when they cool down.

Using the formula Q = mcΔT:
Heat absorbed by brakes Q = (90.7 kg)(1.400 J/g°C)(312°C)

Note that 1 kg = 1000 g, so we convert the mass of brakes from kg to grams.

Q = (90700 g)(1.400 J/g°C)(312°C) = 39930720 J

This same amount of heat is transferred to the tires. We can now calculate the specific heat of the tires.

Q = mcΔT, where m is mass, c is specific heat, and ΔT is the temperature change.

Rearranging the formula to solve for specific heat c:

c = Q / (mΔT)

Substituting Q = 39930720 J, m = 123000 g (since tires are 123 kg), and ΔT = 172°C:

c = 39930720 J / (123000 g * 172°C)

c = 39930720 J / 21156000 g°C

c = 1.89 J/g°C

The specific heat of the tires is approximately 1.89 J/g°C.

A mixture in which the particles are distributed evenly, but particles keep their properties.

a) element


b) heterogenous mixture


c) homogenous mixture


d) compound

Answers

Answer: Homogeneous mixture

Explanation:

Element: It is a substance made up from only one type of atom. It is not a mixture.

Heterogeneous mixture: This is a mixture having two or more substances that are unevenly distributed. The substances can be easily separated.

Homogeneous mixture: This is a mixture having two or more substances that are evenly distributed. These cannot be easily separated. The substances retain their original properties.

Compound: It is a substance which is composed of two or more elements in a specific ratio. these are evenly distributed but in this the elements do not retain their original properties.

Hence, from the above points, it is easily justified that homogeneous mixtures are the ones, where the particles are evenly distributed and also retain their original properties.

you rent a car in Germany with a gas mileage rating of 12.8km/L. What is its rating in miles per gallon?

Answers

so one liter is about 2. something gallons so at 12.8 km/l you would get about 30 mpg which is insane but yeah

Answer: The mileage rating of the car is 30.05 miles per gallon

Explanation:

We are given:

Mileage rating = 12.8 km/L

To convert this level into milligrams per deciliters, we use the conversion factor:

1 mile = 1.61 km

1 gallon = 3.78 L

Converting the above rating into miles per gallon, we get:

[tex]\Rightarrow (\frac{12.8km}{L})\times (\frac{1mile}{1.61km})\times (\frac{3.78L}{1 gallon})\\\\\Rightarrow 30.05miles/gallon[/tex]

Hence, the mileage rating of the car is 30.05 miles per gallon

7.321 mg of an organic compound containing carbon, hydrogen, and oxygen was analyzed by combustion. The amount of carbon dioxide produced was 17.873 mg and the amount of water produced was 7.316 mg. Determine the empirical formula of the compound.

Answers

The molecular formula is C₄H₈O.

We must calculate the masses of C, H, and O from the masses given.

Mass of C = 17.873 mg CO₂ × (12.01 mg C/44.01 mg CO₂) = 4.8774 mg C

Mass of H = 7.316 mg H₂O × (2.016 mg H/18.02 mg H₂O) = 0.818 48 mg H

Mass of O = Mass of compound - Mass of C - Mass of H

= (7.321 – 4.8774 – 0.818 48) mg = 1.6251 mg

Now, we must convert these masses to moles and find their ratios.

From here on, I like to summarize the calculations in a table.

Element     m/mg      n/mmol     Ratio    Integers  

     C          4.877 4    0.406 11   3.9984         4

     H         0.818 48   0.811 99   7.9944         8

     O         1.625 1      0.101 57   1                    1

The empirical formula is C₄H₈O.

Missing words please help me

Answers

The first one is 206 then move, body, then protects, calcium,strong,blobs

there are
[tex]206[/tex]
bones in the human skeleton. Our bones are very
[tex]strong[/tex]
the skeleton does three very important jobs. It helps us to
[tex]move[/tex]
around, it supports the
[tex]body[/tex]
and it
[tex]protects[/tex]
the organs inside the body. Bones are made from
[tex]calcium[/tex]
and they are very hard. They are
[tex]alive[/tex]
and grow with us. Witought our skeletons, we would look like
[tex]blobs[/tex]



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