the limiting reagent is nitrogen gas.
steps:
write out balanced equation: 3H2 + N2 = 2NH3
convert to moles to find how much NH3 each yields
find molar mass of each
10 g H2 (1 mol/2.016g) (2NH3/3H2) = 3.31 mol NH3
26g N2 (1mol/28.02g)(2NH3/1N2)=1.86 mol NH3
since N2 yields less NH3, it is the limiting reagent.
What is the weight in grams of 0.45 moles of gold(Au)?
Answer:
88.63494750000001
Explanation:
Convert moles Gold to gram.
calculate denisty in grans per milliliter 25.0 mL having a mass of 19.7 g
A 0.100 g sample of a carboxylic acid is burned in oxygen, producing 0.178 g of CO2 and 0.0734 g of H2O. Determine the empirical formula of the carboxylic acid.
The empirical formula of the carboxylic acid is C₃H₆O₂.
For determination of the empirical formula of the carboxylic acid.
As you know, one mole of water, contains 2 moles of hydrogen. This means that the percent composition of hydrogen in water will be
2× 1.00794 g/mol / 18.015 g/mol × 100 = 11.19% H
What this means is that every 100 g of water will contain 11.19 g of hydrogen. In your case, the 0.2349-g sample of water will contain
0.2349 g water⋅ 11.19 g H / 100 g water = 0.026285 g H
Similarly, one mole of carbon dioxide, CO₂, contains one mole of carbon. The percent composition of carbon in carbon dioxide will be
1 ×12.011 g/mol / 44.01 g/mol × 100 = 27.29% C
Once again, this tells you that every 100 g of carbon dioxide will contain
27.29 g of carbon. In your case, you will have
0.5706g H₂O ⋅ 27.29 g C /100g H₂O = 0.15572 g C
The mass of carbon + hydrogen originally present in the carboxylic acid sample will be
m C + H = 0.026285 g + 0.15572 g =0.18201 g
The initial mass of the sample was equal to 0.3200 g. This tells you that the sample also contains oxygen
m oxygen = 0.3200 g −0.18201 g = 0.13799 g O
So, now that you know how many grams of each element were present in the initial sample, use their molar masses to convert these to moles
For C: 0.15572g /12.011g/mol = 0.012965 moles C
For H: 0.026285 g/1.00794g/mol = 0.026078 moles H
For O: 0.13799g/15.9994g/ mol = 0.0086247 moles O
Now, to get the compound's empirical formula, you need to find the smallest whole number ratio that exists between the number of moles of each element in the compound.
To do that, divide these values by the smallest one to get
For C: 0.012965 moles / 0.0086247 moles = 1.5032 ≈ 1.5
For H: 0.026078moles /0.0086247 moles =3.0236≈ 3
For O: 0.0086247moles /0.0086247 moles = 1
This means that you have
C₁.₅H₃O₁
Since you're looking for the smallest whole number ratio that exists between the elements, multiply each subscript by 2 to get
C₁.₅H₃O₁ * 2 = C₃H₆O₂
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calculate the energy required to excite an electron from n=2 to n=4
Explanation:
taking atom as hydrogen than
answer is +2.55
just apply Delta energy=energy in 4th orbit -energy in 2nd orbit
[tex]energy = - 13.6 \times z ^{2} \div n {}^{2} [/tex]
so here you can find answer
Calculate the density, in g/mL, of a liquid that has a mass of 0.115 g and a volume of 0.000275 L.
Density of the liquid is 0.418g/mL
The liquid sample has a volume of 0.000275 L. We can convert this to mL (because we are asked to find the density in g/mL):
mass of liquid= 0.115 grams
volume of the liquid, V= 0.000275L
Density is defined as the ratio of mass per unit volume
Now we must convert the unit of volume from L to ml as liter is SI unit which goes with Kilogram
volume in ml = 0.000275 ml/l x 1000 =0.275 ml
Density d = mass/volume
= 0.115/ 0.275
= 0.418 g/mL
Hence the density of the liquid is 0.418 g/mL
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Which statement correctly compares a hypothesis and a theory? A theory is a prediction for a specific situation, while a hypothesis is used to make predictions for many similar situations. A hypothesis is a prediction for a specific situation, while a theory is used to make predictions for many similar situations. A theory provides an explanation, but a hypothesis does not. A hypothesis provides an explanation, but a theory does not.
The statement that correctly compares a hypothesis and a theory is that a hypothesis is a prediction for a specific situation, while a theory is used to make predictions for many similar situations (option B).
What is a hypothesis?A hypothesis is a tentative conjecture explaining an observation, phenomenon or scientific problem that can be tested by further observation, investigation and/or experimentation.
On the other hand, a scientific theory is a coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed.
A theory is simply a hypothesis confirmed by observation or experiment.
Therefore, the statement that correctly compares a hypothesis and a theory is that a hypothesis is a prediction for a specific situation, while a theory is used to make predictions for many similar situations.
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What is true of a molecule?
A. Each molecule of a compound has different properties.
B. Each atom of a molecule is the same
C. All molecules of a compund have the same properties.
D. All molecules of a compound have one type of atom
The true statement about a molecule is that all molecules of a compound have the same properties and is therefore denoted as option C.
What is an Atom?
This is referred to as the smallest unit of matter without the release of electrically charged particles which include proton, electron etc.
Atoms combine together to form molecules and they are involved in the formation of chemical compounds such as NaCl etc. It consists of identical molecules which means that all of them have the same properties which is therefore the reason why option C was chosen as the most appropriate choice.
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Answer:
All molecules of a compound have the same properties.
Explanation:
Identify the arrows that represent the process of cooling.
liquid
gas
solid
The arrows B, C, and E represent the process of cooling.
Solid state: In the solid state, the molecules are arranged in a regular and fixed pattern. The molecules in a solid are closely packed that is the solid particles can not move.
Liquid state: In the liquid state, the molecules are present in an irregular pattern. The molecules are closely packed but particles can move.
Gaseous state: In the gaseous state, the molecules are present in an irregular manner. The molecules of gases are not closely packed and can move freely.
Therefore, the solid changes to liquid on heating, and the liquid changes to solid after cooling.
Liquid changes to a gaseous state on heating while gases changes to liquid on cooling.
Solid changes to gas on heating and gases change to solid after cooling.
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10
Determine the formal charges on all atoms in the molecules.
a. :N=N=N:
b. : CEO:
C.
:0:
O.N.O
Formal charge = number of valence electron - 1/2 bonded electron - lone pair electron
a. N3 = number of valence electron - 1/2 bonded electron - lone pair e-
= 5 - 2/4 - 4
= -1
b. CO = number of valence electron - 1/2 bonded electron - lone pair e-
Charge on carbon
= 4 - 2 - 6/2
= -1
charge on oxygen
number of valence electron - 1/2 bonded electron - lone pair e-
= 6 - 2 - 6/2
= +1
c. NO3
by making structure we found that each oxygen has different charge in this compound.
O = -1, -1 , 0
N = 0
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This is an impossible formula. Pretend it is real.
If you had 1 mol of Cr8(PO4)3 how many moles of Cr would there be?
Remember that you should never include a 1 as a subscript but for the sake of clarity for this problem you may see a 1 as a subscript.
Fe = 52.00 g/mol
P = 30.97 g/mol
O = 16.00 g/mol
Make sure your answer includes TWO decimal places.
The number of mole of Cr in 1 mole of Cr₈(PO₄)₃ is 8.00 moles
Description of Cr₈(PO₄)₃From the formula of the compound, Cr₈(PO₄)₃, the following were obtained:
8 moles of Cr3 moles of P12 moles of OHow to determine the number of mole of Cr in 1 mole of Cr₈(PO₄)₃From the formula, we can see that 8 moles of Cr are present.
Thus, 1 mole of Cr₈(PO₄)₃ will contain = 1 × 8 = 8.00 moles of Cr
Therefore, we can conclude that 1 mole of Cr₈(PO₄)₃ contains 8.00 moles of Cr
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an enclosed gas is at a pressure of 143,95kpa .if the volume is increased by 40% at constant temperature. what is the new pressure in kilopascals ?
All processes for which the temperature stays constant are described by Boyle's law.
Boyle's law is expressed as p1 * V1 = p2 * V2, where p1 and V1 are starting pressure and volume, respectively. The ultimate values of these gas parameters are p2 and V2.
Boyle's law formula can be stated in a variety of ways, depending on the parameter we want to estimate. Let's imagine we wish to determine the pressure that results from changing a gas' volume under isothermal conditions. The Boyle's law equation thus reads: p2 = p1 * V1 / V2 or p2 / p1 = V1 / V2.
As we can see, the final-to-initial pressure ratio is the opposite of the volume ratio.
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A sample of natural gas was found to contain 0.070% (percent by volume) of hydrogen sulfide, H2S. Calculate the mass of H2S present in 2.00 L of natural gas at 298 K.
The mass of H₂s present in 2.00 L of natural gas at 298 K is 0.002156 g.
What is the volume of hydrogen sulfide in 2.00 L of natural gas at 298 K?The volume hydrogen sulfide in 2.00 L of natural gas at 298 K is calculated as follows:
Volume of hydrogen sulfide = percent composition * volume of natural gas
Volume of hydrogen sulfide = 0.07/100 * 2.00 L
Volume of hydrogen sulfide = 0.014 L
The given temperature is standard temperature.
Density of H₂s at STP is equal to 1.54 g/L.
mass of H₂s = density * volume
mass of H₂s = 0.0014 * 1.54
mass of H₂s = 0.002156 g
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Which of the following statements correctly describes density?
Answer:
Helper
Explanation:
is the expaltin of the explatin
Can somebody please help me
Answer:
A.
Explanation:
Spiders are creepy.
That your answer.
Name the material sent into space by a supernova
Answer:
Nebula Was Sent Into Space By Supernova
This shock wave compresses the material it passes through and is the only place where many elements such as zinc, silver, tin, gold, mercury, lead and uranium are produced. Over several months the gases cool and fade in brightness and join the debris of interstellar space.
Answer: This shock wave compresses the material it passes through and is the only place where many elements such as zinc, silver, tin, gold, mercury, lead and uranium are produced. Over several months the gases cool and fade in brightness and join the debris of interstellar space.
Explanation:
6) Calculate the mass of a liquid with a density of 2.5 g/mL and a volume of 15 mL.
The mass of a liquid with a density of 2.5 g/mL and a volume of 15 mL is 37.5g.
What is Density ?
Density is the measurement of quantity or mass per unit of volume in a particular substance. Its units are grams per centimeters cube (g/cm³) or kilograms per liter (kg/l)
⇒ g/cm³ can also be written as g/mL because 1cm³ = 1mL
What is Volume ?
Volume is a measure of space. When measuring the volume of a liquid which is sometimes referred to as capacity, the units liters (L) and milliliters (mL) are used.
What is Mass ?Mass is defined as amount of matter present in a body. Gram (g) and kilogram (kg) are the common units.
density = mass / volume
mass = density × volume
= 2.5 g/mL × 15 mL.
= 37.5 g
Since density is given in g/mL and volume is given in mL, we can keep the unit of mass in grams (g).
Thus we can conclude that the mass of liquid is 37.5g
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What is the mass (in grams) of 10.00 L of propane vapor (C3H8) at STP?
The mass (in grams) of 10.00 L of propane vapor ([tex]C_3H_8[/tex]) at STP is 19.668 g
One mole of gas requires 22.4 L of space at STP.
Moles of[tex]C_3H_8[/tex] = 10.0L/22.4L = 0.446 mol
Mass of [tex]C_3H_8[/tex] = 0.446×44.1 = 19.668 g
STP, or standard temperature pressure, refers to the nominal atmospheric conditions at sea level. The temperatures and pressures are 0 degrees Celsius and 1 atmosphere, respectively. In addition to other professionals, the STP value is crucial for physicists, chemists, engineers, pilots, and navigators.STP in chemistry is the abbreviation for Standard Temperature and Pressure. STP is most frequently employed for doing calculations for gases.To learn more about STP visit:
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2. How many grams of copper(II) chloride contain 2.17 grams of Cu²+?
4.63 gram of Cooper(II) chloride contain 2.17 grams of Cu²+
Molar mass of copper(II) chloride = 134.45 g/mol
Molar mass of copper = 63 grams
The average mass of an element's atoms expressed in atomic mass units is known as its atomic mass (amu, also known as daltons, D). The mass of each isotope is multiplied by its abundance to produce the atomic mass, which is a weighted average of all the isotopes of that element.
63 gram of copper is present in 134.45 g/mol of copper(II) chloride
1 gram copper is present in copper(II) chloride = 134.45/63 = 2.13 gram
2.17 gram Cu²+ in copper(II) chloride = 2.13 gram x 2.17 gram = 4.63 gram
Hence, 4.63 gram of Copper(ii) chloride contain 2.17 grams of Cu²+
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Which postulate of Dalton's atomic model was later changed and why?
According to postulates of the Dalton's atomic theory, atoms of same element are identical in all respects i.e., in shape, size, mass and chemical properties. However, after the discovery of isotopes, it was modified as : atoms of same element may not be similar in all respects
Choose one of the following articles to read. Then you will summarize the article in 3-5 sentences and give a 2-3 sentence reflection on your personal thoughts on the article. Your answer must be in complete sentences and use proper sentence structure. Your answers must contain the listed terms and use them in the correct context. CAPITALIZZE the listed term within your answer. Label your answer the with question # you choose.
Do Astronauts need sunscreen in space?
Be sure to use the following terms in your summary: ultraviolet radiation, electromagnetic waves, wavelength
Why is the color blue so rare in nature?
Be sure to use the following terms in your summary: waves, visible light, wavelengths
Explain the difference between radiation and radioactivity
Be sure to use the following terms in your summary: electron, wave, electromagnetic radiation
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What is the volume of each of the following at STP?
A.44.00 g N2
B.0.25 mol NH3
Considering the definition of STP conditions, you obtain:
A. 44 grams of N₂ will ocupy at STP 35.168 L.
B. 0.25 moles of NH₃ will ocupy at STP 5.6 L.
Definition of STP conditionsThe STP conditions refer to the standard temperature and pressure. Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
Definition of molar massThe molar mass of substance is a property defined as the amount of mass that a substance contains in one mole.
Volume in this caseIn this case, you have:
44 grams of N₂, with a molar mass of 28 g/mole0.25 moles NH₃You can apply the following rule of three to know the number of moles of N₂: if 28 grams of the compound are contained in 1 mole, 44 grams are contained in how many moles?
number of moles of N₂= (44 grams× 1 mole)÷ 28 grams
number of moles of N₂= 1.57 moles
Now, you can apply the following rules of three to know the volume of N₂ and NH₃:
if by definition of STP conditions 1 mole of N₂ occupies a volume of 22.4 liters, 1.57 moles occupies how much volume?volume of N₂= (1.57 moles× 22.4 L)÷ 1 mole
volume of N₂= 35.168 L
if by definition of STP conditions 1 mole of NH₃ occupies a volume of 22.4 liters, 0.25 moles occupies how much volume?volume of NH₃= (0.25 moles× 22.4 L)÷ 1 mole
volume of NH₃= 5.6 L
Finally, you obtain:
A. 44 grams of N₂ will ocupy at STP 35.168 L.
B. 0.25 moles of NH₃ will ocupy at STP 5.6 L.
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A German automobile's gas mileage is 18km/L. Convert this quantity to miles per gallon.
Answer:
42
Explanation:
miles per gallon = kilometers per liter × 2.35
Compounds that have a high degree of ionization in solution are known as what
When a neutral molecule is exposed to a solution, it splits into charged ions, which is known as ionization. The degree of ionization of acids and bases is determined by the degree of dissociation of compounds into their constituent ions. Strong acids and bases have a higher degree of ionization than weak acids and bases.
What is the degree of ionization?The Ionisation degree denotes the strength of an acid or a base. A strong acid is said to completely ionize in water, whereas a weak acid is said to ionize only partially. Because there are different degrees of acid ionization, there are also different levels of weakness, which can be expressed quantitatively.
Why do acids and bases have such high ionization levels?Ionization of these bases results in the formation of hydroxyl ions (OH). As a result, the degree of ionization of acids and bases is determined by the degree of dissociation of compounds into their constituent ions. Strong acids and bases have a high degree of ionization when compared to weak acids and bases.
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Add curved arrows(s) to show the resonance using the following pattern: a lone pair (on nitrogen) next to a pi bond. Modify the second structure given to draw the new resonance structure. Include lone pairs and charges in your structure. Using the + and - tools to add charges to an atom, and use the single bond tool to add/remove double bonds.
Answer:
ddddxddddddddddddddddddddddddd
What is the limiting reactant if 0.5 g Al is reacted with 0.5 g CuCl2?
What is the theoretical yield of copper produced by this reaction?
Taking into account the reaction stoichiometry ,CuCl₂ is the limiting reagent and the theoretical yield of copper produced is 0.2363 grams.
Reaction stoichiometryIn first place, the balanced reaction is:
2 Al + 3 CuCl₂ → 3 Cu + 2 AlCl₃
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
Al: 2 molesCuCl₂: 3 molesCu: 3 molesAlCl₃: 2 molesThe molar mass of the compounds is:
Al: 27 g/moleCuCl₂: 134.44 g/moleCu: 63.54 g/moleAlCl₃: 133.35 g/moleThen, by reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
Al: 2 moles ×27 g/mole= 54 gramsCuCl₂: 3 moles ×134.44 g/mole= 403.32 gramsCu: 3 moles ×63.54 g/mole= 190.62 gramsAlCl₃: 2 moles ×133.35 g/mole= 266.7 gramsLimiting reagentThe limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
Limiting reagent in this caseTo determine the limiting reagent, it is possible to use a simple rule of three as follows: if by stoichiometry 54 grams of Al reacts with 403.32 grams of CuCl₂, 0.5 grams of Al reacts with how much mass of CuCl₂?
mass of CuCl₂= (0.5 grams of Al× 403.32 grams of CuCl₂)÷ 54 grams of Al
mass of CuCl₂= 3.734 grams
But 3.734 grams of CuCl₂ are not available, 0.5 grams are available. Since you have less mass than you need to react with 0.5 grams of Al, CuCl₂ will be the limiting reagent.
Definition of theoretical yieldThe theoretical yield is the amount of product acquired through the complete conversion of all reagents in the final product, that is, it is the maximum amount of product that could be formed from the given amounts of reagents.
Theoretical yield of copperConsidering the limiting reagent, the following rule of three can be applied: if by reaction stoichiometry 403.32 grams of CuCl₂ form 190.62 grams of Cu, 0.5 grams of CuCl₂ form how much mass of Cu?
mass of Cu= (0.5 grams of CuCl₂× 190.62 grams of Cu)÷ 403.32 grams of CuCl₂
mass of Cu= 0.2363 grams
Then, the theoretical yield of copper produced is 0.2363 grams.
SummaryIn summary, you obtain:
CuCl₂ is the limiting reagent.the theoretical yield of copper produced is 0.2363 grams.Learn more about theoretical yield:
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calculate the energy of an EM wave having wavelength 4.2nm
The energy of an electromagnetic wave that has a wavelength of 4.2nm is 4.731 × 10-¹⁷ J.
How to calculate energy of a wave?The energy of a wave can be calculated using the following formula:
E = hf
Where;
E = energyh = Planck's constant (6.626 × 10-³⁴J/s)f = frequency of the waveHowever, the frequency must be calculated first as follows:
λ = v / f
Where;
λ = wavelengthv = speed of light (3 × 10⁸m/s)4.2 × 10-⁹ = 3 × 10⁸/f
f = 7.14 × 10¹⁶Hz
Energy = 6.626 × 10-³⁴ × 7.14 × 10¹⁶
Energy of the wave = 4.731 × 10-¹⁷ J
Therefore, the energy of an electromagnetic wave that has a wavelength of 4.2nm is 4.731 × 10-¹⁷ J.
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expaln the conductivity of magnesium
Magnesium is not a good conductor. Hence, the conductivity of magnesium is not good.
Magnesium is placed in group 2 of the periodic table. It has 2 valence electrons which are in the fully filled s-subshell. When the subshell is fully filled, the electrons are not available to move to conduct. For example, group 1 has half filled subshell which allows the electrons to move.
But, how does magnesium conduct? As its subshell is fully filled and therefore no electrons are available to move.
In group 2 metals, there is a property called s-p hybridization. The s- and p- subshells overlap so that metals can now move to the unfilled states of the p-subshell.
Hence, magnesium is not a good conductor.
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For any large collection of randomly selected chlorine atoms:
a. what is the average atomic mass of chlorine in amu?
An atomic mass unit is defined as 1/12 th of the mass of carbon-12 atom.
The mass of an atom is mainly due to its protons and neutrons in the nucleus.
Weight of a proton is 1.6 x 10^-27 kg
Weight of a neutron is 1.6 x 10^-27kg
However weight of an electron is 9 x 10^-31kg and hence is negligible in calculation of amu
A chlorine atom has 17 protons in its nucleus and 18 neutrons in its nucleus
Its atomic number is 17
Amu weight of Cl= weight of protons+ weight of neutrons
=17+18
=35amu
Hence the average atomic mass unit of chlorine atoms will be 35 amu
Disclaimer:
The value is taken for easier calculation and is not accurate upto 3 decimals
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1.3511, 2.473, 5.687524, 7.555, 8.235 rounded to one significant figure. Please help, I'm stuck!
Answer:
1,2,6,8,8
Explanation:
1.3511=1
2.473 =3
5.687524=6
7.555=8
8.235=8
What is the chemical equation for frying an egg
The given chemical reaction is :
Calcium Oxide (s) + Water (l) → Calcium Hydroxide (s)
Molecular Changes : A chemical reaction is one in which the replying substances experience changes at the molecular position. This means that bonds between tittles of the reactants are broken, and tittles are changed or rearranged to produce commodity new. Chemical reaction can be reversible or unrecoverable.
What happens when frying an egg ?
Frying an egg is a chemical response. It's an illustration of an endothermic response or bone that takes in heat to make the response do. An egg is made up of proteins and water, and the thralldom also contains fat. When an egg is hotted , the proteins begin to change their structure. Protein motes are veritably complex, made up of long chains of structure blocks called amino acids. These chains are also folded and twisted to make complicated molecular structures. Hotting the egg adds energy, which causes the motes to begin to move and lose their shape. Bonds holding the shape of the protein motes together begin to break, unfolding the proteins and allowing them to spread out. New bonds are formed, and water evaporates out of the egg, changing it into a semi-solid. The egg has experienced anon-reversible chemical response, as it can not be changed back into its raw state.
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