The mass of the pure aluminum that can be extracted from 655 g of aluminum oxide is equal to 346 g. Therefore, option (C) is correct.
What is the balanced chemical equation?A balanced equation in which the number of atoms of each element should be same on the both sides of the equation. From the law of conservation of mass, the total mass of the elements on the reactant side as well as the product side should be equal in a balanced chemical equation.
The balanced chemical equation of the decomposition of aluminum oxide:
2Al₂O₃ (s) → 4 Al (s) + 3O₂ (g)
Given, the mass of the aluminum oxide = 655 g
The number of moles of aluminum oxide = 655/101.96 = 6.42 mol
2 moles of aluminum oxide form aluminum = 4 mol
Then 6.42 mol aluminum oxide form aluminum = (4/2) ×6.42 = 12.85 mol
The mass of the aluminum can be extracted = 12.84 ×27 = 346.9 g
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Sulfuryl chloride is in equilibrium with sulfur dioxide and chlorine gas: so2cl2(g) so2(g) + cl2(g) a system with a volume of 1. 00 l is in equilibrium at a certain temperature with p(so2cl2) = 1. 00 bar and p(so2) = p(cl2) = 0. 10 bar. By how much will the number of moles of so2cl2 at equilibrium change if the volume is reduced to 0. 50 l? (a) increase 1-10% (b) increase 11-50% (c) decrease 1-10% (d) decrease 11-50%
The volume is decreased to 0. 50L, the number of moles of SO₂Cl₂at equilibrium will increase by 1–10% option - a is correct.
What is Le Chatelier's Principle.The guiding idea of Le Chatelier is as follows: A shift in the position of the equilibrium results from a change in one of the variables that characterize a system in equilibrium and cancels out the effects of that change.
Now to solve this question first we have to know the Le-chatelier's
Principle
The Principal that if a system in chemical equilibrium is subjected to a disturbance it tends to change in a way that opposes this disturbance.
SO₂Cl₂(g) ⇄ SO₂(g) + Cl₂(g)
Initially, there is one molecule at the left hand side of the reaction and two molecules are on the right. But, the Partial pressure of molecules on RHS is lower than LHS. Concentration of RHS molecules is Lower, forward reaction is more favorable.
Decreasing volume would result in increasing the total pressure.
Now, according to Le chatelier's Principle, the equilibrium will shift in such a way to oppose change under compression. Since there are more moles of Products than reactants, to counteract the increased pressure. The equilibrium will shift to LHS increasing the moles
of SO₂Cl₂ but since the concentration (Partial Pressure)
of SO₂Cl₂, it will not increase more than 10%
Hence, answer will be (a) Increase 1-10%.
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→
1. A + 2B→→→→D
The rate of formation of D in the above reaction is found experimentally to be
independent of the concentration of B
and to quadruple when the
concentration of A is doubled.
Write the rate law for the reaction
Answer:
[A]²
Explanation:
Since the formation is independent of D, D is 0 order.
Since a quadruples when it is doubled it can be written as
2A^X= 4
To find the unknown power we can assume A= 1 to make the math simple. So When a = 2 (Because you doubled it) raised to X power it will equal 4
so the unknown power is 2
Making the rate law
[a]²[b]⁰
or simply just
[A]²
Given 750 g of oxygen gas and chlorine gas and an excess of the other reactants, how much potassium chloride (grams) will be produced?
2MnO2 + 4KOH + O2 + Cl2 -> 2KMnO4 + 2KCl + 2H20
must show work
Answer:
=2h20−2kmno4+2mno2+2ckl+cl2+4hko+o2
Explanation:
step-by-step.
2mno2+4koh+o2+cl2−2kmno4+2kcl+2h20
=2mno2+4hko+o2+cl2+−2kmno4+2ckl+2h20
Identify at least two physical properties (streak, fracture, etc.) of a mineral while using examples of common minerals that prominently feature those properties. Provide links or screenshots of the discussed minerals to illustrate the highlighted properties. Also, explain what mineral group it belongs to and why.
The two physical properties of a mineral can be color, streak and even cleavage also.
Color, streak, cleavage, hardness, specific gravity, fracture, luster, and crystal structure are only a few of the many diverse characteristics. I'll speak specifically about color and shine as they relate to diamonds and how they significantly impact the value of the individual stone. Diamonds are a type of carbon polymorph.
Polymorphism, as used in materials science, refers to the fact that a solid material can exist in more than one crystal structure or form. Isomerism in the form of polymorphism. The phenomena can be seen in any crystalline substance. A chemical element's polymorphism is referred to as allotropy. Pharmaceuticals, agrochemicals, pigments, dyestuffs, meals, and explosives all have practical applications for polymorphism. "A reversible transition of a solid crystalline phase at a given temperature and pressure (the inversion point) to another phase of the same chemical composition with a different crystal structure," according to IUPAC, describes a polymorphic transition.
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If 1 gram (g) of glycogen is split into maltose (no maltotriose or dextrins are produced),
what is the total mass of the product?
If 1 gram (g) of glycogen is split into maltose: The total mass of the product would be 2 grams (g).
Mass of Maltose Resulting from the Breakdown of 1 Gram of GlycogenWhen 1 gram of glycogen is broken down into maltose, the result is two molecules of maltose, each having a molecular weight of 342.29 g/mol. Therefore, the total mass of the product is equal to 2 x 342.29 g/mol, or 684.58 g/mol, which is equal to 2 grams (g).
This is because each molecule of maltose is composed of two molecules of glucose, which have a mass of 342.29 g/mol each. Therefore, when the 1 gram of glycogen is split into maltose, the total mass of the product is 2 grams (g).
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what is the balance of S8+Br2=S3Br7
Answer:
3S₈ + 28Br₂ => 8S₃Br₇
Explanation:
Start with either sulfur (S) or bromine (Br) and balance ...
3S₈ + Br₂ => 8S₃Br₇ or S₈ + 7/2Br₂ => S₃Br₇
Balance the remaining reactant ...
3S₈ + 56/2Br₂ => 8S₃Br₇
Remove fractions by multiplying by the fraction's denominator
2(3S₈ + 56/2Br₂ => 8S₃Br₇) => 6S₈ + 56Br₂ => 16S₃Br₇
Reduce to smallest whole number ratio => standard equation at STP ...
3S₈ + 28Br₂ => 8S₃Br₇
describe the phase and temperature chacges that will occur if you heat 50.0 g of h2o in its solid state at -8 C until it all vaporizes
The phase and temperature changes that will occur if you heat 50.0 g of H2O in its solid state at -8 C until it all vaporizes is that the solid H2O will transition to a liquid state at 0 C and then to a vapor at 100 C.
What is vapor?Vapor is an aerosolized suspension of tiny liquid particles that are released into the air. It is made up of a mixture of water and other chemicals, such as nicotine, propylene glycol, and other flavorings. Vapor is produced when heated liquid, such as e-liquid, is turned into a vapor. This vapor can be inhaled and exhaled in a manner similar to smoking a traditional cigarette, which is why vapor has become an alternative to traditional smoking.
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Fill in the blank.
When using a graduated cylinder you must look at ________ of the liquid when taking readings.
When using a graduated cylinder you must look at Meniscus of the liquid when taking readings.
How to Read a Graduated Cylinder?The surface at the center of the meniscus, not the top of the ring of liquid clinging to the graduated cylinder's wall, must be read in order to read a graduated cylinder correctly. This "center" will be the meniscus's lowest point for the majority of liquids. The center of the meniscus will be the highest point of the liquid for a very small number of liquids, such as mercury. Your line of sight must be level with the meniscus's center of curvature in order to interpret it correctly.
Reading a graded cylinder is a matter of paying close attention to the details once the measurement interval has been established and the meniscus has been assessed. Read the numbered line below while keeping your eyes level with the meniscus's middle and looking straight down.
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please help me find the density for this object
Answer:
D
Explanation:
Density is d=m/v
We have mass, it's 540
The volume is length*width*height
So it's 5*6*4=120 cm^3
540/120=4.5 g/cm^3
It's cm^3 because volume is in cubic centimeters.
What synthetic goal is achieved by subjecting an alkene to an oxymercuration demercuration reaction sequence
An alkene is subjected to an oxymercuration demercuration reaction sequence to attain a synthetic aim is the conversion of an alkene into an alcohol.
The oxymercuration reaction involves the addition of a hydroxymercury(II) compound (Hg(OH)2 or Hg(OAc)2) to the alkene in the presence of a strong base, such as sodium hydroxide (NaOH). This results in the formation of an intermediate alkoxymercury(II) compound, which can then be converted into an alcohol through the demercuration step. In the demercuration step, the alkoxymercury(II) compound is treated with a reducing agent, such as sodium borohydride (NaBH4), which reduces the mercury(II) to mercury(0) and converts the alkoxymercury(II) compound into an alcohol. In summary, the oxymercuration-demercuration reaction sequence is a two-step process that converts an alkene into an alcohol by adding a hydroxymercury(II) compound to the alkene in the presence of a base and then reducing the intermediate alkoxymercury(II) compound with a reducing agent.
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Which of these statements best describes how a star chart should be held while facing north?
The edge of the map labeled east should be held towards the observer.
The edge of the map labeled south should be held towards the observer.
The edge of the map labeled south should be held on the left of the observer.
The edge of the map labeled east should be held on the right of the observer.
Answer: The edge of the map labeled south should be held towards the observer.
Explanation: I just took the test with this and it was right
10. What would the new concentration be, in percentage, of 1.5 ml of a 10% solution that has been increased with normal saline to 3.0 ml
The 1.5 ml of a 10% solution that was made into a 3.0 ml solution by adding normal saline now has a new concentration of 5%.
The amount of material in a certain area is referred to as concentration in chemistry. Another definition states that concentration is the ratio of a solution's solute to its entire solution or solvent. Mass per unit volume is a common way to express concentration. However, moles or units of volume can also be used to express the solute concentration. Concentration could be per unit mass instead of volume. Concentration can be computed for any mixture, despite often being used with chemical solutions.
By mathematically dividing the mass, moles, or volume of the solute by the mass, moles, or volume of the solution, one may calculate the concentration (or, less commonly, the solvent).
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2C(s) + 2H2(g) + 52.4kJ ⇋ C2H4(g)
A) Which direction will the system shift when temperature is decreased?
B) Describe what will happen to the concentration of hydrogen gas when the temperature is increased.
C) State one way which you could increase the concentration of C2H4.
Answer:
A. The equilibrium will shift towards the right, towards the formation of products
B. The concentration of hydrogen gas will decrease as more of it is used in the formation of products
C. Increasing the temperature at which the reaction is performed will increase the concentration of C2H4, the product of the reaction.
Explanation:
The given reaction is an exothermic reaction as it requires the addition of extra energy of about 52.4KJ in the form of heat for the reaction to proceed towards product formation.
According to L' Chtler principle, when an external constraint is applied to A given system in equilibrium, equilibrium position will shift so as to annul the effect ofnthe constraint imposed on the system.
Therefore, the answers tonthe questions above are given below as follows :
A. The equilibrium will shift towards the right, towards the formation of products in order to remove the effect of the additional heat since the forward reaction is endothermic.
B. The concentration of hydrogen gas will decrease as more of it is used in the formation of products .
C. Increasing the temperature at which the reaction is performed will increase the concentration of C2H4, the product of the reaction as the equilibrium will shift towards the right; formation of products.
Fe(OH)3->Fe2O3->Fe->FeCl2->Fe(OH)2
[tex]Fe(OH)3- > Fe2O3- > Fe- > FeCl2- > Fe(OH)2[/tex], represents a set of possible chemical reactions that Fe(OH)3, or iron(III) hydroxide, can undergo.
In the first reaction, Fe(OH)3 is converted into Fe2O3, or iron(III) oxide, through the process of thermal decomposition. This reaction occurs when Fe(OH)3 is subjected to high temperatures, causing it to break down into Fe2O3 and water vapor.
In the second reaction, Fe2O3 is reduced to Fe, or elemental iron, through the process of electrolysis. This reaction involves passing an electric current through a solution of Fe2O3, causing the Fe2O3 to be reduced to Fe at the cathode and oxygen to be produced at the anode.
In the third reaction, Fe is converted into FeCl2, or iron(II) chloride, through the process of chlorination. This reaction involves adding chlorine gas to a solution of Fe, causing the Fe to be converted into FeCl2 and hydrogen gas.
In the fourth reaction, FeCl2 is converted into Fe(OH)2, or iron(II) hydroxide, through the process of acidification. This reaction involves adding an acid to a solution of FeCl2, causing the FeCl2 to be converted into Fe(OH)2 and hydrochloric acid.
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The correct question is:
Explain this chemical reaction [tex]Fe(OH)3- > Fe2O3- > Fe- > FeCl2- > Fe(OH)2[/tex]
16. INFER: Magnesium and Sodium atoms are about the same size. How does the size of a magnesium ion with a 2+ charge compare with that of a sodium ion with a single (+) charge?
The atomic size of a magnesium ion is smaller than the atomic size of sodium ion.
The distribution of electrons in an element's atomic orbitals is known by its electronic configuration. Atoms' electron configurations adhere to a standard nomenclature in which all atomic subshells that contain electrons are arranged in a sequence with the number of electrons they each hold expressed in superscript.
the electronic configuration of each element's electrons:
Na-[tex]1s^{2}2 s^{2}2 p^{6} 3s^{1}[/tex]
Mg-[tex]1s^{2} 2s^{2} 2p^{6} 3s^{2}[/tex]
The magnesium atom is smaller than the sodium atom because its nuclear charge is larger (12+) than that of sodium (11+), according to the electron configuration. The electrons will be drawn more strongly to the magnesium nucleus, reducing the size of the atom.
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Who goes to K12 and if so what grade
Answer:
I do
Explanation:
But i am unable to share my grade because of personal info.
Answer:
11 th
Explanation:
Find the kinetic energy of a boy of mass 6.5kg running at a velocity of 6.0m/s
Explanation:
Given,
Mass(m)=6.5kg
Velocity(v)=6 m/s
K.E.=1/2×mv^2
=1/2×6.5×6^2
=1/2×6.5×36
=117 J
How will you justify presence of 18 elements in 5th period and presence of 32 elements in 6th period?
The orbitals within subshells are filled in the sequence of increasing energy. The filling can choose from the 5s, 4d, as well as 5p sub-shells. Consequently, there are 18 total components in period 5.
There are 18 atoms in the 5th grade of the periodic table, never 32. Reason l=0, 1, 2, and 3 and n=5. The energy of the accessible electron shells 4d, 5s, and 5p grows in the correct sequence: 5s4d5p. and since there are a total of 9 accessible orbitals, 18 electrons could fit.
The fourth period includes 18 elements owing to the 10 extra electrons which the 3d orbitals can hold since the 3d sublevel doesn't really fill before the 4s sublevel.
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Why are all the elements in group 18 relatively unreactive meaning they do not gain lose or share electrons with other atoms?
Elements of group 18 belongs to the family of noble gases with a general electronic configuration ns²np⁶, where the valence shell is completely filled.
The elements of group 18 are considered to be noble because they have a completely filled valence shell due to which they donot have the tendency to gain, lose or share their valence electrons with other atoms. Thus, they are highly unreactive.
The elements belonging to noble gas family are: Helium (He), Neon (Ne), Argon(Ar), Krypton(Kr), Xenon(Xe), Radon(Rn).
under conditions of standard pressure and temperature, these elements exists as gases with very low chemical reactivity so they are known as inert gases.
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What is the name of this molecule?
O A. Butane
O B. Propane
O C. Propene
O D. Butene
The molecule represented below is Butane.
Important things to know about Butane Butane is an organic compound consisting of 4 carbon atoms. it is also a straight chain alkane with unsaturated bonds.its molecular formulae is C4H10.Can be used as a refrigerant.looking at the structure give each point represents a carbon atom, placing a C on each point gives you a total of 4, making it to be butane.See picture attached for a vivid illustration of butane.
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Answer:
Butane
Explanation:
i just took tha test
Herrington found a substance that tastes sour, turns litmus paper red and has a pH of 1.4. Herrington found a(n)
Answer: Herrington found an ACID.
Explanation:
Acid is defined as a substance which when dissolved in water, produces hydroxonium ion as the only positive ion. It is a proton donor. Acid can be used for the production of fertilizers, dyes, detergents, drugs, plastic and explosives.
The characteristics of an acid includes:
--> They have sour taste
--> In pH scale, values below 7 indicates acidity increasing downwards from 6 to 1.
--> strong acids are corrosive.
--> substances called indicators give specific colours in acidic media. For example: blue litmus turns red; phenolphthalein turns colourless; and methyl orange turns pink.
--> they react with active metals, that is, those above hydrogen on the activity series, to liberate hydrogen gas.
--> they react with bases to produce salts and water as the only products. This reaction is known as neutralisation reaction.
The above characteristics about acid shows that the substance found by Herrington is an ACID.
A sample of magnesium metal reacts with 45.0 mL of 3.0 M solution of hydrochloric acid. How many moles of HCl are reacting
moles of HCl are reacting is [tex]135\times10^{-3}[/tex]
In the International System of Units, the mole is used to measure material quantity. The number of a substance's elementary entities that are present in an object or sample depends on the amount of that substance. A solute's molar concentration is used to represent how much of a solute there is per unit volume of a solution or how much of a chemical species there is in a solution.
Magnesium reacts with hydrochloric acid to generate a salt of magnesium chloride and release hydrogen gas.
Mg(s) +HCl(aq) [tex]\rightarrow[/tex] [tex]MgCl_{2}[/tex](aq)+[tex]H_{2}[/tex](g)
molarity =[tex]\frac{moles of solute}{volume of solution \:(l)}[/tex]
molarity of Mg is 3.0M volume of solution is 45ml
now, 3M=[tex]\frac{moles of solute}{45\times 10^{-3} \:(l)}[/tex]
moles of mg = 135 millimoles.
now according to the reaction by using stoichiometry
moles of Mg = moles of HCl
moles of HCl =135 millimoles =[tex]135\times10^{-3}[/tex]
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What volume of 0.75 M H₂SO4 is required to neutralize 25.0
mL of 0.427 M KOH?
A volume of 0.02845 L is required to neutralize this acid-base reaction.
To neutralize an acid with a base, you need to react with equal molar amounts of the two. The balanced chemical equation for the neutralization of sulfuric acid (H₂SO₄) with potassium hydroxide (KOH) is as follows:
H₂SO₄ + 2 KOH → K₂SO₄ + 2 H₂O
The molarity of a solution is a measure of the number of moles of solute per liter of solvent. To find out how many moles of H₂SO₄ you need to neutralize 25.0 mL of 0.427 M KOH, you first need to convert the volume of KOH to liters, using the conversion factor 1 L/1000 mL.
25.0 mL KOH × (1 L/1000 mL) = 0.025 L KOH
Then, use the molarity of the KOH solution to find out how many moles of KOH you have:
0.427 M KOH × 0.025 L KOH = 0.010675 moles KOH
Since the balanced chemical equation shows that 1 mole of H₂SO₄ reacts with 2 moles of KOH, you need twice the number of moles of KOH, or 0.010675 moles × 2 = 0.02135 moles H₂SO₄.
Finally, use the molarity of the H₂SO₄ solution to find out how much volume you need:
(0.02135 moles H₂SO₄) ÷ (0.75 M H₂SO₄) = 0.02845 L H₂SO₄
So you need a volume of 0.02845 L of 0.75 M H₂SO₄ to neutralize 25.0 mL of 0.427 M KOH. This is equivalent to 28.45 mL of 0.75 M H₂SO₄.
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Fe2O3(s) +
_CO(g) - Fe(l) +
_CO2(g)
Balanced?
what will the boiling point of CHCL3 be when the atmospheric pressure exerted on its surface is 101.325
The boiling point of CHCl₃ at a pressure of 101.325 kPa is 61.8°C (143.24°F).
What is boiling point?The boiling point is the temperature at which the pressure exerted on a liquid by the environment equals the pressure exerted by the vapor of the liquid. Under these conditions, the application of heat converts the liquid to vapor without raising the temperature.
At any temperature, the liquid partially vaporizes into the space above until the pressure exerted by the vapor reaches a characteristic value called the vapor pressure of the liquid at that temperature. As the temperature rises, the vapor pressure increases. At boiling point, vapor bubbles form in the liquid and rise to the surface.
The boiling point of a liquid changes along the pressure. The normal boiling point is the temperature at which the vapor pressure equals normal atmospheric pressure at sea level (760 mm [29.92 inches] of mercury). At sea level, water boils at 100°C (212°F).
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The complete question is as follows:
What will the boiling point of CHCL3 be when the atmospheric pressure exerted on its surface is 101.325 KPa?
Calculate the amount of heat energy required to heat up 21.5 grams of ice from -15 °C to 10°C.
Answer:
8.74kj
Explanation:
There are three steps
Warming up the ice to its melitng point. THe nergy required to melt it completely. The energy requiered to warm up the water to a certain temp.
It can be seen by the three equations written
What group could X be in if it forms ions with ammonium in the ratio of (NH4)3X?
X could be in Group
If it forms ions with ammonium in the ratio of (NH4)3X, X could be in Group IV A. Group IVA (14) metals form cations with +4 charge, although tin (Sn) and lead (Pb) can form cations having +2 charge.
What does the term "coordinate bond" mean?A covalent link (a shared pair of electrons) in which both electrons originate from the same atom is known as a coordinate bond (also known as a dative covalent bond). Two atoms sharing a pair of electrons make a covalent connection. Because the electron pair is drawn to both nuclei, the atoms are kept together.
How is a coordinate bond recognized?An arrow pointing from the donor to the acceptor, with a positive charge on the donor and a negative charge on the acceptor, is used to symbolize a coordinate bond.
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How i an electron orbital different from an orbit what do the hape of the orbital hown in Figure 14
An orbit is a set route along which electrons spin around the nucleus of an atom, whereas an orbital is a region where the chance of finding any electron is calculated.
What is electron?The electron is a subatomic particle with an initial electric charge of -1. Electrons are the first generation of the lepton particle family and are often regarded as elementary particles due to the lack of known components or substructure. An electron is a negatively charged subatomic particle that can be attached to or released from an atom (not bound). A bound electron is one of the three major kinds of particles within an atom, the other two being protons and neutrons. The nucleus of an atom is made up of electrons, protons, and neutrons.
Here,
An orbit is a fixed path along which electrons spin around an atom's nucleus, whereas an orbital is an area where the probability of finding any electron is determined.
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which type of reaction is represented by the generic equation AB+CD --->AD+CB?
combustion
decomposition
single replacement
double replacement
Answer:
4. Double replacement
Explanation:
The generic equation shows that two compounds are being swapped, which is an indication of a double substitution reaction.
Correct answer double replacement.
So the correct answer is D) Double replacement.
Balance the below equation:
____NH_3+ 〖____O〗_2 → ____NO+ ____H_2 O
How many grams of NO can be produced from 12 g of NH3 and 12 g of O2?
What is the limiting reactant? What is the excess reactant?
How much excess reactant remains when the reaction is over?
Answer:
O₂ is the limiting reactant
0.406 moles of ammonia remains after the reaction goes complete.
Explanation:
Balanced reaction is:
4NH₃ + 5O₂ → 4NO + 6H₂O
Let's determine the moles of each reactant:
12 g . 1mol / 17g = 0.706 moles of ammonia.
12 g . 1mol / 32g = 0.375 moles of oxygen.
4 moles of ammonia react to 5 moles of oxygen
Then, 0.706 moles of ammonia may react to (0.706 . 5) /4 = 0.882 moles
We only have 0.375 moles of oxygen and there are needed 0.882. O₂ is the limiting reactant. Definetely ammonia is in excess.
5 moles of oxygen react to 4 moles of ammonia
Our 0.375 moles may react to (0.375 . 4) / 5 = 0.3 moles
We have 0.706 moles of NH₃ and we only need 0.3
After the reaction goes complete (0.706 - 0.3) = 0.406 moles of ammonia still remains.