Answers
ANSWER
The number of moles of helium is 4.0 mol
EXPLANATION
Given information
\(\text{ The number of helium atoms is 2.4}\times10^{24}\text{ atoms}\)To find the number of moles of helium, follow the steps below
Step 1: Write the formula for calculating the number of moles
\(\text{ Mole }\frac{\text{ number of atoms}}{\text{ Avogadro's number}}\)\(\text{ Recall, that Avogadro's number is 6.022}\times10^{23}\)Step 2: Substitute the given data into the formula in step 1
\(\begin{gathered} \text{ Mole = }\frac{\text{ number of atoms}}{\text{ Avogadro's number}} \\ \text{ } \\ \text{ Mole = }\frac{2.4\times10^{24}}{6.022\times10^{23}} \\ \\ \text{ Mole = }\frac{2.4}{6.022}\times10^{24-23} \\ \\ \text{ Mole = 0.3985}\times10 \\ \text{ Mole = 3.985} \\ Mole\approx4.0\text{ mol} \end{gathered}\)Hence, the number of moles of helium is 4.0 mol
Related Questions
For parts a & b below, derive only the initial value problem set up.
A tank of capacity 200 gallons holds 100 gallons of water with 25 pounds of sugar in solution. Pure water is poured into it at the rate of 2 gallons per minute, and the well-stirred mixture flows out of this tank at a rate of gallon per minute and into the second tank that initially contained 50 gallons of fresh water. The well-stirred mixture in the second tank is allowed to leave the tank at the same rate (1 gal/min).
1. Determine an Initial value problem that satisfied by the amount of sugar in the first tank (Tank A).
2. Determine an Initial value problem that satisfied by the amount of sugar in the second tank (Tank B).
Answers
Answer:
Explanation:
From the given information:
Let y(t) be the amount of sugar in tank A at any time.
Then, the rate of change of sugar in the tank is given by:
\(\dfrac{dy}{dt}= (rate \ in ) - ( rate \ out )\)
The rate of the sugar coming into the tank is 0
\(\text{rate of sugar going out }= \dfrac{y(t) \ pound}{100}\times \dfrac{1 }{min} \\ \\ = \dfrac{y}{100} \ pound/min\)
\(So; \\ \\ \\ \dfrac{dy}{dt} = 0 - \dfrac{y}{100} \\ \\ \implies \dfrac{dy}{y }= -\dfrac{dt}{100 } \\ \\ \implies dx|y| = -\dfrac{t}{100}+C \\ \\ \implies e*{In|y|}= e^{-\dfrac{t}{100}+C} \\ \\ \implies y = Ce^{-\dfrac{t}{100}}\)
Initial amount of sugar = 25 Pounds
Now; y(0) = 25
25 = Ce⁰
C = 25
So; y(t) = 25 \(e^{-\dfrac{t}{100}\)
Thus, the amount of sugar at any time t = \(\mathbf{25 e^{^{-\dfrac{t}{100}}}}\)
B) For tank B :
\(\dfrac{dy}{dt}= 1 - \dfrac{y}{50 } \\ \\ \dfrac{dy}{dt}= \dfrac{50-y}{50} \\ \\ \dfrac{dy}{50-y }= \dfrac{dt}{50}\)
According to erikson, unsuccessful completion of the first psychosocial stage will result in
Answers
Answer:
Unsuccessful completion of this stage can result in an inability to trust, and therefore an sense of fear about the inconsistent world. It may result in anxiety, heightened insecurities, and an over feeling of mistrust in the world around them.
Hope this helps!
Answer: Unsuccessful completion of this stage can result in an inability to trust, and therefore an sense of fear about the inconsistent world. It may result in anxiety, heightened insecurities, and an over feeling of mistrust in the world around them.
Explanation:
(b) Calculate the pH of the following buffer solution.
A solution of 10.0g each of formic acid (CH COOH (Mwt 46g/mol) and Potassium formate (CKHCOO
(Mwt 84g/mol) dissolved in 1.0 litre of water.
(formic acid ka = 1.8 x 104)
Answers
The pH of the buffer solution can be determined using Henderson equation. The pH is obtained as 4.51.
What is buffer solution?A buffer solution is a solution with constant pH and its maintains the pH of a solution upto a desired point. The pH of a buffer solution is determined using Henderson equation as written below:
pH = Pka + ln [A-]/[HA]
Where, [A-] be the concentration of the salt and [HA ] be that of the acid.
Given that 10 g of acid and its salt are dissolved in 1 L solution. Thus,
no.of moles of acid = 10 g / 46 = 0.217 in L means 0.217 M
concentration of salt = 10 g/ 84 g in one L = 0.119 M.
ka = 1.8 × 10⁴
pka = log Ka = 4.25
pH = 4.25 + ln (0.119 / 0.217)
= 4.51
Therefore, the pH of the solution is 4.51.
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Homework Answered Due Today, 11:59 PM
The reaction 3H₂(g) + N₂(g) → 2NH3(g) has an enthalpy of reaction of -92.6 kJ/mol. If 1 g of hydrogen and 2 g of nitrogen are
reacted, how much heat is produced (kJ)?
Answers
The amount of heat energy produced when 1 g of hydrogen and 2 g of nitrogen are reacted, is -6.61 KJ
How do i determine the heat energy produced?First, we shall obtain the limiting reactant. Details below:
3H₂ + N₂ -> 2NH₃
Molar mass of N₂ = 28 g/molMass of N₂ from the balanced equation = 1 × 28 = 28 g Molar mass of H₂ = 2 g/molMass of H₂ from the balanced equation = 3 × 2 = 6 gFrom the balanced equation above,
28 g of N₂ reacted with 6 g of H₂
Therefore,
2 g of N₂ will react with = (2 × 6) / 28 = 0.43 g of H₂
We can see that only 0.43 g of H₂ is needed in the reaction.
Thus, the limiting reactant is N₂
Finally, we the amount of heat energy produced. Details below:
3H₂ + N₂ -> 2NH₃ ΔH = -92.6 KJ
Molar mass of N₂ = 28 g/molMass of N₂ from the balanced equation = 1 × 28 = 28 gFrom the balanced equation above,
When 28 grams of N₂ reacted, -92.6 KJ of heat energy were produced.
Therefore,
When 2 grams of N₂ will react to produce = (2 × -92.6) / 28 = -6.61 KJ
Thus the heat energy produced from the reaction is -6.61 KJ
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Consider a disubstituted aromatic compound. The parent name is benzene and there is a chloro and bromo substituent. Disubstituted benzenes can be described using the terms ortho, meta and para, depending on their relative distance from each other. The terms are often just abbreviated as o, m and p. In addition, the IUPAC name can use locant numbers instead of the descriptor. Br
Select the correct names for the structure.
1. 1-bromo-3-chlorobenzene
2. 3-bromo-1-chlorobenzene
3. meta-bromochlorobenzene
4. o-bromochlorobenzene
5. ortho-bromochlorobenzene
6. m-bromochlorobenzene
Answers
Answer:The correct names for the structure are:
--> 1. 1-bromo-3-chlorobenzene.
--> 3. meta-bromochlorobenzene.
--> 6. m-bromochlorobenzene.
Explanation:
Benzene is the simplest member of the aromatic hydrocarbons. It has a ring structure consisting of six carbon and six hydrogen atoms. This equally means that a benzene can have up to six substituents. One of the chemical properties is that benzene and other members of its series undergo substitution reaction whereby one or more of its six hydrogen atoms is replaced by monoatomic reagents.
Disubstituted benzene consists of two substituents which are described based on either numerical locants or specific words for the three possible forms.
The numerical locant method are used the same naming substitutes of other hydrocarbons. From the question, the numerical locant method was derived through using the following steps:
--> the functional group is benzene
--> there are two substituents which includes bromine( written as bromo) and chlorine ( written as chloro)
--> while placing the number, it's done alphabetically ('1-bromo' comes before '3-chloro') in a clockwise manner. This is to give chorine the lowest locant number.
The second naming method for a disubstituted benzene is the the ortho-, meta-, para- (or their singel letter equivalent) nomenclature method. This is only used for benzene structures.
--> ortho or O : this is used when the substituents are close to each other in the benzene ring.
--> meta or (m) : This is used when the substituents are separated by one carbon in the benzene ring.
--> para or (p): This is used when the substituents are across each other in the benzene ring
From the question, the bromine substituent is separated from the chlorine by one carbon atom, therefore it's meta-bromochlorobenzene or m-bromochlorobenzene.
23 2 C,H,.+ 13 0,8 CO, + 10 H,0
Butane is a hydrocarbon that is a liquid at room temperature making it easier to store and be used as an ignition source for many things like lighters and grills. How many grams of C,H,, will be needed to produce 20.00 grams of o, in this reaction? a. 2.4 grams C,H, b. 5.6 grams C.H.
Answers
Describe what happens between the valence electrons in an Ionic Bond.
How is that different from a covalent bond?
Answers
Answer:
In an ionic bond, the elctrons are transferred. For example, NaCl has an ionic bond because Na loses an electron and the Cl atom gains the electron. However in a covalent bond, the electrons are shared equally. Covalent bonds usually occur between two nonmetals.
Explanation:
The heat of reaction for the combustion of propane is –2,045 kJ. This reaction is: C3H8(g) +502 (g) 3CO2 (g) + 4H2O (g). Determine the standard heat of formation of propane.
Answers
Answer:
\(\Delta _fH_{C_3H_8}=-102.7kJ/mol\)
Explanation:
Hello,
In this case, we can consider that the given heat of combustion is indeed the heat of reaction since it corresponds to the combustion of propane, which is computed by using the heat formation of all the involved species as shown below:
\(\Delta _cH=3*\Delta _fH_{CO_2}+4*\Delta _fH_{H_2O}-\Delta _fH_{C_3H_8}-5*\Delta _fH_{O_2}\)
Thus, since the heat of formation of gaseous carbon dioxide is -393.5 kJ/mol, water -241.8 kJ/mol and oxygen 0 kJ/mol, the heat of formation of propane is:
\(\Delta _fH_{C_3H_8}=3*\Delta _fH_{CO_2}+4*\Delta _fH_{H_2O}-5*\Delta _fH_{O_2}-\Delta _cH\\\\\Delta _fH_{C_3H_8}=3*(-393.5)+4*(-241.8)-5*0-(-2045)\\\\\Delta _fH_{C_3H_8}=-102.7kJ/mol\)
Best regards.
4. Consider Limitations Students were given the following sets of items and
asked, for each set, to identify which item had greater thermal energy. For
which set would this task be most difficult? Explain.
Set 1: 5 g of iron at 45°C and 10 g of iron at 45 °C
Set 2: 10 g of water at 30°C and 10 g of water at 50°C
Set 3: 32 g of copper at 50°C and 32 g of nickel at 50°C
Answers
Answer:set 3
Explanation:
Why are antiparallel beta sheets more stable than parallel beta sheets?
Answers
Answer:
The side chains of the amino acids alternate above and below the sheet
Explanation:
Hydrogen bonds are formed between the amine and carbonyl groups across strands. ... Antiparallel ß sheets are slightly more stable than parallel ß sheets because the hydrogen bonding pattern is more optimal.
a tire will burst if the air inside it reaches a pressure greater than 1.4 x 10^3 kpa. at what temperature will the tire burst if it has a volume of 30L and contains 2.5 mol of air? assume that the air behaves as an ideal gas. assuming that these values are representative, do you need to worry about your car tire bursting from overheating of they are in good condition?
Answers
This extremely high temperature indicates that under normal conditions, you do not need to worry about your car tire bursting from overheating as it is unlikely to reach such extreme temperatures.
To determine the temperature at which the tire will burst, we can use the ideal gas law equation:
PV = nRT
Where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
Rearranging the equation to solve for temperature, we have:
T = PV / (nR)
Given that the pressure threshold for bursting is 1.4 x 10^3 kPa, the volume is 30 L, and the number of moles of air is 2.5 mol, we can substitute these values along with the ideal gas constant R = 8.314 J/(mol K) into the equation.
T = (1.4 x 10^3 kPa) * (30 L) / (2.5 mol * 8.314 J/(mol K))
Converting kPa to Pa and L to m^3, and simplifying the equation, we find:
T ≈ 20,993 K
This extremely high temperature indicates that under normal conditions, you do not need to worry about your car tire bursting from overheating as it is unlikely to reach such extreme temperatures.
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WILL GIVE BRAINLIEST AND LOTS OF POINTS
I rlly need help its due tomorrow
Alma is planning on joining the track team this year. In preparation for the season, Alma decides she wants to start running on her own to get in shape.
The next day, Alma decides to work on short sprints instead of long-distance running. Explain how Alma’s body cells would obtain energy differently when she sprints than when she runs long distances. When would her body’s cells make energy more efficiently? Why?
Answers
Alma is using ATC-PC which is a quick fuel source. Which is the first energy used in short and quick uses of energy. While it gives the max energy at first, after about 10 seconds it runs out. Which then short term energy starts. Which uses carbs as energy. This gets to max energy after a little bit and after a few minutes, it starts to run out. Then long term energy kicks in. This uses oxygen to provide energy, while it lasts for a long time, it takes time to reach max energy. This can also fail if your respiratory system or cardiovascular system can't provide enough oxygen.
B
1
2
3
4
5
sodium (Na)
boron (B)
O magnesium (Mg)
lithium (Li)
6
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10
An atom of element X has one more shell of electrons than an atom of beryllium, but it has one less valence electron
than beryllium. Which element is element X?
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Answers
Sodium has three shells while beryllium has two shells. Beryllium has one more valence electron compared to sodium.
Valence electron are the electrons present in outer most shell of the atom Atomic number of beryllium is 4 and its electronic distribution is 2,2. this indicates there are 2 electrons in outermost shell Atomic number of sodium is 11 and its electronic distribution is 2,8,1.This indicates there is 1 electron in outermost shell.Beryllium is found in period 2 of group 2 of the periodic table, which is also known as the alkaline earth metal group. Sodium is found in period 3 of group 1 of periodic table,also called alkaline earth metal group. Thus ,sodium has one less valence electron in outermost shell as compared to berylliumLearn more about valence electron here-
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The kinetic energy of a 23.2-g object moving at a speed of 98.7 m/s is ________ J. The kinetic energy of a 23.2-g object moving at a speed of 98.7 m/s is ________ J. 0.950 145 113 1450 113000
Answers
The kinetic energy of a 23.2-g object moving at a speed of 98.7 m/s is 113.30 J. Option D
The kinetic energy of an object can be calculated using the formula: KE = (1/2)mv^2, where KE is the kinetic energy, m is the mass of the object, and v is the velocity or speed of the object.
Given:
Mass (m) = 23.2 g = 0.0232 kg
Speed (v) = 98.7 m/s
Substituting these values into the formula, we can calculate the kinetic energy:
KE = (1/2)(0.0232 kg)(98.7 m/s)^2
KE = (1/2)(0.0232 kg)(9756.09 m^2/s^2)
KE ≈ 113.30 J
Therefore, the kinetic energy of a 23.2-g object moving at a speed of 98.7 m/s is approximately 113.30 J.
It's worth noting that the question is repeated twice, but the answer remains the same. The kinetic energy of the object is determined by its mass and speed, and both calculations yield the same result. Option D
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i) __________are rigid due to strong (ii)___________ of attraction between the particles
Answers
Answer:
Liquid Solids are rigid due to strong glass of attraction between the particles.
Explanation:
which statement about the sun is true?
A.The sun is a red giant
B. The sun will become a red giant
C. The sun began as a red giant
D. The sun cannnot become a reg giant
Answers
The Law of Conservation of Mass states that mass changes before and after a change.
True
False
Answers
How do you determine the percent yield of a chemical reaction?
Answers
Answer:
percentage yield =[ experimental yield / theoretical yield] x 100
Explanation:
(NH4) (OH) is compound soluble or insoluble?
Answers
An inorganic fungicide, microbiocide, and herbicide is ammonium hydroxide. It is very soluble in water and non-volatile.
In Ammonium hydroxide Ammonium Chloride, which hydroxide is insoluble?Because of its extremely high solubility product, magnesium hydroxide, also known as Magnesium hydroxide, is insoluble in Ammonium hydroxide. Nevertheless, when Ammonium Chloride is present, the following reaction occurs, and the magnesium hydroxide dissolves.
Why does water include Ammonium hydroxide?Ammonia is dissolved in water to form ammonium hydroxide (Ammonium hydroxide). The substance, also known as ammonia or ammonia water, is used as a cleaner and in the production of plastics, rubber, fertiliser, and textiles. It is a clear, colourless liquid with a strong to barely detectable ammonia odour.
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Which of the following compounds would form an acid when dissolved in water as an aqueous solution?
NaCl
NO2
H2SO3
HCl
Answers
Answer:
Explanation:
An acid is a substance that can donate protons (H+) to water when dissolved in it, resulting in an increase in the concentration of H+ ions in the solution.
When NaCl (sodium chloride) is dissolved in water, it dissociates into its individual ions, Na+ and Cl-. These ions do not donate protons to water, so NaCl does not form an acid when dissolved in water.
NO2 (nitrogen dioxide) is a neutral compound, it does not donate protons to water and does not form an acid when dissolved in water.
H2SO3 (sulfurous acid) is an acid, when dissolved in water, it donates protons to water and forms H+ ions and SO3- ions.
HCl (hydrochloric acid) is an acid, when dissolved in water it donates protons to water and forms H+ ions and Cl- ions.
So the answer is H2SO3 and HCl are the compounds that would form an acid when dissolved in water as an aqueous solution.
Ice has a density of 0.92g/cm3. It will float in water.
Answers
The density of pure water is 1 g/cm^3.
Its density is 0.98 g cm 3 at room temperature, in comparison with the handiest zero.92 g cm 3 for ice, a reality that has to be defined through atomic, and molecular concepts. If ice has been no longer much less dense than water, it might sink, having a devastating impact on lake backside ecosystems. believe it or now not, ice is honestly about 9% much less dense than water. for the reason that water is heavier, it displaces the lighter ice, causing the ice to glide to the pinnacle.
The density of ice is about 90 percent that of water, but that could range because ice can contain air, too. meaning that about 10 percent of an ice cube or iceberg will be above the water line. The density of water is maximum at four∘C, and the density of the ice is much less than the water due to its susceptible intermolecular pressure of attraction. as the density of water is more, it's miles heavier than ice. therefore ice floats on the floor of the water. Ice continually floats due to the fact it's far less dense than everyday water. because frozen water molecules shape a crystal.
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How can the affect of radiation on healthy cells can be reduced when treating cancer?
Answers
The affect of radiation on healthy cells can be reduced when treating cancer by focusing the radiation on the cancerous cells.
How can the effect of radiation on healthy cells can be reduced when treating cancer?These side effects are also known as late side effects, which causes the human healthy cells after some time. The Doctors try to protect the healthy human cells by lowering the power of the radiations as possible. The radiation dose is balanced between being high enough to kill cancer cells, yet low enough to limit damage to healthy cells. If we use the advancement of technology of dose conformity such as IMRT, SBRT, and IGRT, then we can get rid of such dangerous radiations.
So we can conclude that the affect of radiation on healthy cells can be reduced when treating cancer by focusing the radiation on the cancerous cells.
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Balance the entire chemical
reaction using an atom inventory.
What is the correct whole
number coefficient for propane,
C3H8?
[?]C3H8+ [ 0₂
]CO2+[ ]H2O
Answers
The balanced chemical equation for the combustion of propane with oxygen is: C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
To balance the equation, first balance the carbon atoms on both sides of the equation. There are three carbon atoms in the propane molecule and three in the carbon dioxide molecule, so balance the carbon atoms by putting a coefficient of 3 in front of the CO₂ molecule.
C3H8 + 5O2 → 3CO₂
Next, balance the hydrogen atoms. There are eight hydrogen atoms in the propane molecule and four in the water molecule, so balance the hydrogen atoms by putting a coefficient of 4 in front of the H₂O molecule.
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Finally, balance the oxygen atoms. There are five oxygen atoms on the left side and 10 on the right side, so balance the oxygen atoms by putting a coefficient of 5 in front of the O₂ molecule.
Therefore, the correct whole number coefficient for propane, C3H8, is 1.
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heating curve iron
at what temperature does the substance begins to boil
at what temperature does a substance begin to melt
at what temperature is a substance for a liquid and a gas
at what temperature is the substance both a solid and a liquid
Answers
The substance begins to boil at 2750⁰C, the substance begins to melt at 1500⁰C, the temperature at which the substance is both a liquid and a gas at 2750⁰C, temperature is the substance both a solid and a liquid at 1500⁰C.
Heating curves are the graphical correlations between heat added to a substance. When viewed from a cooling perspective, ie. loss of heat, it is the cooling curve.
The gradient of the cooling curve is related to the heat capacity, the thermal conductivity of the substance, and the external temperature. The more heat is required to change the temperature of the substance, the slower it cools, so the smaller the gradient of the curve. The higher the thermal conductivity, the faster heat is transferred, so the faster the substance cools.
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The scientists could show that the paint at the crime scene was from a 1992 Chevy. The specific chip of paint that was recovered also matched the chip of paint that was taken from the suspect’s car. What is TRUE about this evidence?
A.
They were unable to find class nor individual characteristics.
B.
They were only able to find class characteristics.
C.
They were able to find both class and individual characteristics.
D.
They were only able to find individual characteristics.
Answers
The affirmation "They were only able to find class characteristics." is true, therefore, option B is correct.
What are class characteristics?Class characteristics are part of the physical evidence. These are those objects that tell us if a crime has been committed or that they would have a connection with a crime or with the perpetrator of this crime with the victim. In this case it would be the type of paint chip that was taken from the suspect that matched the one found at the scene.
Class characteristics specifically, they are the properties that we are going to associate with a specific group of suspects, which decreases the number of suspects but does not connect us directly with just one culprit. Such as paint, blood or fibers.
Therefore, we can confirm that the correct option is B. They were only able to find class characteristics.
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Which best describes what a refrigeration system would do?
O It adds cold air through the room.
O It moves the thermal energy to another place.
O Itallows coolant to release cold air into the room.
O It transfers energy from the ground.
Answers
Answer:
It moves the thermal energy to another place.
Explanation:
Answer:
B is correct in edge
How does Gas Trapping bottles Monitor Volcanos?
( put in your own words don’t look up on internet )
I will give brainlst If you answer correctly.
Answers
Answer: the pressure releases gas. The two most abundant gases are sulfur dioxide and carbon dioxide, and if levels of these gases increase,
Explanation:
Q1. Consider the gravitational interactions among Earth, the Sun, and the Moon. Does this constitute a system? If so, what are its boundaries? Is it open or closed? What forms of energy are involved?
Answers
When two objects descend towards one another, the potential energy related to the gravitational field is released (transformed into kinetic energy).
The potential energy that a huge item has in relation to a different massive object due to gravity is known as gravitational energy and gravitational potential energy. When two objects descend towards one another, the potential energy related to the gravitational field is released (transformed into kinetic energy). Bringing two things farther apart increases the gravitational potential energy.
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The nuclei of Three naturally occurring magnesium isotopes have the same number of protons but different numbers of neutrons . Explain Why ? Why does every atom of barium have 56 protons and 56 lectrons? Which subatomic particles in an atom determine its mass number ?
Answers
Based on atomic properties and structure:
Isotopes have the same proton number(atomic number) but different neutron numbers. An atom of barium has 56 protons and 56 neutrons in order to maintain electrical neutrality.The mass number of an atom is determined by the sum of protons and neutrons.What are isotopes?Isotopes are atoms of an element having the same atomic number but different mass numbers.
The difference in mass number is dues to different neutron numbers.
However, because they have the same proton number, they are atoms of the same element.
Neutral atoms contains equal number of protons and electrons.
An atom of barium has 56 protons and 56 neutrons in order to maintain electrical neutrality.
The mass number of an atom is determined by the sum of protons and neutrons.
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Strontium hydroxide reacts with hydrobromic acid to produce Strontium bromide and
water.
Write and balance the chemical reaction above, use it for problems 1-4 below:
1. If 5.50 moles of strontium hydroxide were consumed, how much moles of water are
produced?
2. Find the mass of hydrobromic acid used to produce 7.50 moles water.
3. If 10.8 g of strontium hydroxide were used, how much moles of strontium bromide are
produced?
4. If 13.3 g of hydrobromic acid were consumed, find the mass of the water produced.
Answers
Sr(OH)2 + 2 HCl --> SrCl2 + 2 H2O
To find the moles of water produced when 5.50 moles of strontium hydroxide are consumed, we need to apply the law of conservation of mass. The mass of water produced is equal to the mass of strontium hydroxide consumed. Since strontium hydroxide has a molar mass of 142 g/mol and water has a molar mass of 18 g/mol, 1 mol of strontium hydroxide can produce 9 mol of water. Therefore, 5.50 moles of strontium hydroxide can produce 49.5 mol of water.
Similarly, 7.50 moles of water can be produced by reacting 18 moles of hydrobromic acid with strontium hydroxide. Hydrobromic acid has a molar mass of 79.9 g/mol, so 18 moles of hydrobromic acid would have a mass of 79.9 * 18 = 1435.2 g.
To find the moles of strontium bromide produced when 10.8 g of strontium hydroxide is used, we need to apply the law of conservation of mass again. The mass of the strontium bromide produced is equal to the mass of strontium hydroxide consumed. Since strontium bromide has a molar mass of 410 g/mol and strontium hydroxide has a molar mass of 142 g/mol, 1 mol of strontium bromide can consume 3.23 moles of strontium hydroxide. Therefore, 10.8 g of strontium hydroxide can produce 10.8 / 3.23 = 3.34 moles of strontium bromide.
Finally, to find the mass of water produced when 13.3 g of hydrobromic acid is consumed, we need to apply the law of conservation of mass yet again. The mass of the water produced is equal to the mass of hydrobromic acid consumed. Since hydrobromic acid has a molar mass of 79.9 g/mol, 13.3 g of hydrobromic acid would produce 13.3 / 79.9 = 0.166 moles of water.