Explanation:
A molecular compound is a compound in which atoms share electrons with each other and thus, forms covalent bonds. As a result, molecular compounds are covalent compounds.
In the compound [tex]C_{3}H_{8}[/tex], since hydrogen atom has only one electron and carbon atom has 4 electrons in its valence shell. So, in order to completely fill its octet both carbon and hydrogen will share electrons with each other.
Therefore, [tex]C_{3}H_{8}[/tex] is a covalent compound. Hence, it is also a molecular compound.
In [tex]MgCl_{2}[/tex], magnesium being a metal has excess of electrons and chlorine being a non-metal has deficiency of electrons. Thus, magnesium donates its two electrons to both the chlorine atoms and forms an ionic bond.
Hence, [tex]MgCl_{2}[/tex] is an ionic compound. Thus, it is not a molecular compound.
In [tex]OCl_{2}[/tex], both oxygen and chlorine are non-metals. Hence, they have deficiency of electrons. As a result, both oxygen and chlorine will share electrons in order to complete their octet.
So, there will be formation of covalent bonds. Thus, [tex]OCl_{2}[/tex] is a molecular compound.
[tex]Zn(NO_{3})_{2}[/tex] is an inorganic compound and dissolves in water to form ions of [tex]Zn^{2+}[/tex] and [tex]NO^{-}_{3}[/tex]. Hence, [tex]Zn(NO_{3})_{2}[/tex] is an ionic compound.
Thus, we can conclude that out of the given options, [tex]C_{3}H_{8}[/tex] and [tex]OCl_{2}[/tex] exists as molecules.
Severe shock occurs when blood loss of
30,20,50,10,5%
Which one has more mass a bag of cotton balls or a bag of nails and explain
Determine the entropy change when 1.80 mol of HBr(g) condenses at atmospheric pressure?
Answer:
Entropy change = -168.3 J/mol-K
Explanation:
The entropy change is expressed as:
[tex]DeltaS = \frac{DeltaH}{T}[/tex]
For HBr, the enthalpy of condensation = -19.27 kJ/mol
Temperature T = -67 C = 273 - 67 = 206 K
Therefore, the entropy change when 1 mol of HBr condenses is:
= [tex]\frac{-19.27 kJ/mol}{206 K} =0.0935 kJ/mol-K = -93.5 J/mol-K[/tex]
Thus for the given 1.80 mol of HBr the entropy change would be:
[tex]= 1.80 mol * -93.5 J/mol- K = -168.3 J/mol-K[/tex]
The entropy change when 1.80 mol of HBr(g) condenses at atmospheric pressure can be determined using the equation ΔS = -ΔH/T, where ΔH is the enthalpy change and T is the temperature.
Explanation:The entropy change when a substance condenses can be calculated using the following equation:
∆S = -∆Hvap / T
where:
∆S is the entropy change (J/K·mol)
∆Hvap is the enthalpy of vaporization (kJ/mol)
T is the temperature of condensation (K)
The enthalpy of vaporization of HBr is -19.27 kJ/mol. The temperature at which HBr condenses at atmospheric pressure is its boiling point, which is -67°C. Converting this temperature to Kelvin, we get:
T = -67°C + 273.15 K = 206.15 K
Plugging in these values, we get:
∆S = -(-19.27 kJ/mol) / 206.15 K = 0.09348 kJ/K·mol
Converting kJ to J, we get:
∆S = 0.09348 kJ/K·mol * 1000 J/kJ = 93.48 J/K·mol
Therefore, the entropy change when 1.80 mol of HBr(g) condenses at atmospheric pressure is -168.3 J/K·mol.
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He balanced equation for the reaction of acetylene, c2h2, and oxygen in an acetylene torch is 2 c2h2 + 5 o2 → 4 co2 + 2 h2o. in this reaction the number of grams of oxygen required to react with 0.13 g of acetylene is ________.
To react with 0.13 g of acetylene, 0.399 grams of oxygen are needed based on the molar masses and the balanced chemical equation 2 C2H2 + 5 O2
ightarrow 4 CO2 + 2 H2O.
To find the number of grams of oxygen required to react with 0.13 g of acetylene, we need to use the balanced chemical equation for the reaction and the molar mass of acetylene (C2H2) and oxygen (O2). The balanced chemical equation is 2 C2H2 + 5 O2
ightarrow 4 CO2 + 2 H2O. First, we calculate the molar mass of acetylene, which is (2 imes 12.01 g/mol for carbon) + (2 imes 1.008 g/mol for hydrogen) = 26.04 g/mol. Next, we determine how many moles of acetylene 0.13 g corresponds to by using the molar mass:
moles of C2H2 = 0.13 g / 26.04 g/mol = 0.00499 mol
According to the balanced equation, 2 moles of C2H2 react with 5 moles of O2. Therefore, for 0.00499 moles of C2H2, the moles of O2 required are (0.00499 mol C2H2 imes 5 moles O2) / 2 moles C2H2 = 0.012475 moles O2.
The molar mass of O2 is (2 imes 16.00 g/mol) = 32.00 g/mol. Now, we'll convert moles of O2 to grams:
grams of O2 = 0.012475 moles imes 32.00 g/mol = 0.399 grams of O2
Therefore, 0.399 grams of oxygen are required to react with 0.13 grams of acetylene.
The diagram shows Niels Bohr’s model of an atom.
What happens when the electron moves from the first energy level to the second energy level?
Energy is absorbed, and an emission line is produced.
Energy is released, and an emission line is produced.[wrong]
Energy is absorbed by the atom.
Energy is lost from the atom.
Answer: When the electron moves from the first energy level to the second energy level, energy is absorbed.
Explanation:
When an electron moves from first energy level to the second energy level,energy is being absorbed by the atom which means that the electron jumps from lower energy level to higher energy level.
Bohr's Equation
E=[tex]\frac{-E_0}{n^2}[/tex]
where,
E= energy of an electron in 'n' level (n=1,2,3...etc)
[tex]E_0[/tex]= energy of an electron in ground state.
as we can see from this equation energy is inversely proportional to the n principle quantum number which means that there will be decrease in energy. As the energy is decreasing in magnitude with the negative sign which actually means there is increase in energy.
In the balanced reaction below, what is the mole ratio comparing iron (Fe) and oxygen gas (O2)?
4Fe + 3O2 --> 2Fe2O3
Question options:
4:2
1:3
2:3
4:3
The given balanced reaction is,
[tex] 4Fe(s) + 3O_{2}(g) --->2Fe_{2}O_{3} (s) [/tex]
The stoichiometric coefficients of each element or compound represents the number of moles of that element or compound required for the complete reaction to take place.
The mole ratios of different products and reactants will be:
[tex] \frac{Fe}{O_{2}} = \frac{4 mol Fe}{3 mol O_{2}} [/tex]
[tex] \frac{Fe}{Fe_{2}O_{3}} = \frac{4 mol Fe}{2 Fe_{2}O_{3}} [/tex]
[tex] \frac{O_{2}}{Fe_{2}O_{3}} =\frac{3 mol O_{2}}{2molFe_{2}O_{3}} [/tex]
So the mole ratio comparing iron (Fe) and oxygen gas ([tex] O_{2} [/tex]) is
4 : 3
A sample of chlorine gas is confined in a 5.0 L container at 328 torr and 37 degrees C. How many moles of gas are in the sample?
PLEASE HELP!!! BIG TEST TMRRW!!!! WORK WOULD BE GREATLY APPRECIATED
Answer:
what he/she/they said
Explanation:
Which are isotopes? an atom that has an atomic number of 20 and a mass number of 42 is an isotope of an atom that has which are isotopes? an atom that has an atomic number of 20 and a mass number of 42 is an isotope of an atom that has an atomic number of 20 and a mass number of 40. an atomic number of 21 and a mass number of 42. 22 protons and 20 neutrons. 22 neutrons and 20 protons?
Explanation:
Isotopes are defined as the species which contain same number of protons but different number of neutrons.
As the sum of all the protons present in an atom is known as atomic number. Whereas the sum of total number of protons and neutrons is known as atomic mass.
Hence, isotopes are also defined as atoms with same atomic number but different atomic mass.
For example, an atom that has an atomic number of 20 and a mass number of 42 will contain the following number of neutrons.
Mass number = no. of protons + no. of neutrons
42 = 20 + no. of neutrons
no. of neutrons = 42 - 20
= 22
So, isotope of this atom could be [tex]^{40}_{20}A[/tex]. This means that an element with atomic number of 20 and a mass number of 40.
Thus, we can conclude that an atom that has an atomic number of 20 and a mass number of 42 is an isotope of an atom that has an atomic number of 20 and a mass number of 40.
Since, both of them contains same number of protons but different number of neutrons.
elements can be broken down through ______ processes.
Which of the following correctly describes the size of meteoroids?
Answer:
The correct answer is C. Meteoroids are smaller than comets and asteroids
Explanation: Asteroids go as far as a kilometer in size while meteoroids can be as big as a house. Comets are out of all comparison as they can be up to 80 000 km long.
Which of the following radioisotopes is naturally occurring?
93^239Np
53^131I
102^254No
96^242Cm
Answer:
I - 131 is the correct answer.
I - 131 is the only naturally occuring radioactive isotope among these four options.
Explanation:
Np - 239 - Neptunium is also considered as an artificial element,as only trace amounts of it are found in nature.
And Np - 239 is not a naturally occuring radioactive isotope but it is synthesized artificially.
No - This is an artificial element.That means its not found in nature. Hence all its isotopes are also synthesized artificially.
Cm - This is also an artificial element and all its isotopes are also synthesized artificially.
Np - 239,No - 254,Cm - 242 are radioactive isotopes but they are not naturally occuring radioactive isotopes. But these three are artificially made radioactive isotopes.
And Iodine - 131 is the only naturally occuring radioisotope among these.
What is the total pressure in a 6.00-l flask which contains 0.127 mol of h2(g) and 0.288 mol of n2(g) at 20.0°c?
The total pressure in a 6.00-L flask with a mixture of 0.127 mol H₂ and 0.288 mol N₂ at 20.0°C is calculated using the ideal gas law PV = nRT. After converting the temperature to Kelvin and determining the total moles of gas, the pressure is found to be approximately 1.68 atm.
Explanation:To calculate the total pressure in a 6.00-L flask containing 0.127 mol of H₂(g) and 0.288 mol of N₂(g) at 20.0°C, we can use the ideal gas law, which is PV = nRT. Here, P is the pressure, V is the volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature in Kelvin.
First, convert temperature from Celsius to Kelvin: T = 20.0 + 273.15 = 293.15 K.
Next, use R = 0.0821 L·atm/(K·mol), which is the ideal gas constant appropriate when pressure is in atmospheres and volume is in liters.
Combine the moles of gases: total moles (n₂₄₂al) = 0.127 mol H₂ + 0.288 mol N₂ = 0.415 mol.
Then calculated the pressure using the ideal gas law: P = (nRT)/V = (0.415 mol * 0.0821 L·atm/(K·mol) * 293.15 K) / 6.00 L = 1.68 atm (rounded to two decimal places).
The total pressure in the flask at 20.0°C is therefore approximately 1.68 atmospheres.
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What is the balanced chemical equation for the reaction used to calculate ΔH∘f of SrCO3(s)?
If fractional coefficients are required, enter them as a fraction (i.e. 1/3). Indicate the physical states using the abbreviation (s), (l), or (g) for solid, liquid, or gas, respectively without indicating allotropes. Use (aq) for aqueous solution.
Answer:
[tex]Sr(s)+C(s)+ 3/2O_{2}(g)\rightarrow SrCO_{3}(s)[/tex]
Explanation:
The standard enthalpy of formation (ΔH°f) is defined as the enthalpy change which accompanies the formation of 1 mole of a compound from its constituent elements all of which are in their standard states i.e. either solid (s), liquid (l) , gas (g) or the aqueous phase (aq).
Strontium carbonate (SrCO3) contains 3 elements:
-Strontium (Sr) where the standard state is solid(s)
- Carbon (C) where the standard state is again a solid (s)
- oxygen (O) where the standard state is the gas phase (g)
The balanced chemical equation for the standard enthalpy of formation (ΔH°f) for SrCO3 would be:
[tex]Sr(s)+C(s)+ 3/2O_{2}(g)\rightarrow SrCO_{3}(s)[/tex]
particle will balance the following nuclear equation?
234/91 Pa --> 234/92 U
Answer : Beta particle will balance the following nuclear equation.
Explanation :
The nuclear reaction is,
[tex]^{234}_{91}Pa\rightarrow ^{234}_{92}U+^{-1}_0\beta[/tex]
Beta particle : It forms when a neutron changes into a proton and a high-energy electron.
When the nucleus emits the beta particle, the mass number remains same and the atomic number increases by 1 and the nuclear charge increases by 1.
Hence, the Beta particle will balance the following nuclear equation.
How is most carbon dioxide transported from tissues to the lungs? view available hint(s) how is most carbon dioxide transported from tissues to the lungs? as carbonic acid. as carbon dioxide gas. as bicarbonate ions (hco3−). as protons (h+)?
Check my answers?
Which of the following best describes the motion of the particles in a piece of steel?
None are moving
A few are moving
X All are moving (my choice)
Most are moving
Most solids_____
X are dense and difficult to compress (my answer)
are able to flow
are amorphous
have a disorderly structure
Cyrstals are classified into how many different crystal systems?
4
5
6
X 7 (my answer)
Thanks!
1. All are moving
2. Are dense and difficult to compress
3.
All are correct... 3/3 100%
#1: A gas effuses 4.0 times faster than oxygen (O2). What is the molecular mass of the gas?
A. 1.0 g/mol
B. 2.0 g/mol
C. 4.0 g/mol
D. 7.67 g/mol
**not sure... i think it's either B or C... what do u thinK? @Mertsj :),
If a gas effuses 4.0 times faster than oxygen (O2), the molecular mass of the gas is 2.0 g/mol.
HOW TO USE GRAHAM LAW OF DIFFUSION?The molecular mass of a gas can be calculated using Graham's equation of diffusion as follows:
R1/R2 = √M2/M1
Where R1 and R2 are the rate of diffusion of oxygen and unknown gas respectivelyM1 and M2 is the molecular mass of oxygen and unknown gas respectivelySince the gas effuses 4.0 times faster than oxygen;
R1 = ?R2 = 4R1M1 = 32g/molM2 = ?R1/4R1 = ✓32/M2
(1/16) = x/32
16x = 32
x = 2g/mol
Therefore, If a gas effuses 4.0 times faster than oxygen (O2), the molecular mass of the gas is 2.0 g/mol.
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Sirius is a blue-white star with a surface temperature of about 9800 K. What is most likely the mass of Sirius? 1.0 solar mass 1.4 solar mass 2.0 solar mass 12 solar mass
The answer is actually 2.0 solar masses.
How many moles of copper are needed to react with sulfur to produce 0.25 moles of copper (I) sulfide
Is hot coffee an element a compound a heterogeneous mixture or a homogeneous mixture?
Hot coffee is a homogeneous mixture, consisting of substances that are uniformly distributed and cannot be easily separated.
Explanation:Hot coffee is neither an element nor a compound, but rather a type of mixture. Specifically, hot coffee is a homogeneous mixture. A mixture is a material composed of two or more substances that are combined without a chemical reaction occurring, and in a homogeneous mixture, these substances are uniformly distributed. Therefore, in the case of hot coffee, the coffee solids, water, and any added sugar or cream are thoroughly mixed and cannot be easily separated, which is typical of homogeneous mixtures.
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Hot coffee is a homogeneous mixture, characterized by a uniform composition throughout. It is not a heterogeneous mixture or a compound.
Explanation:Hot coffee is an example of a homogeneous mixture. This classification is due to the uniform composition throughout the coffee, which is a combination of several substances including water, coffee solids, and possibly sugar or milk. It remains homogeneous due to the heat which keeps the solids dissolved. It differs from a heterogeneous mixture, where the composition varies from point to point, and also from a compound, which is a substance formed by chemical union of two or more elements. In contrast, the constituents of a mixture like coffee can be separated by physical changes, such as evaporation.
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Which defines reaction mechanism in chemistry? the mixing of two or more liquids to form a solution the steps in a chemical reaction in which products result from reactants a process in which a product is changed from one physical form to another intermolecular forces that cause attraction or repulsion between nearby particles?
Answer:
the answer is B : the steps in a chemical reaction in which products result from reactants
Explanation:
Sodium tends lose a single electron in natural settings. Based on what you know, what are two other elements that tend to do the same thing?
Question 4 options:
sodium and magnesium
hydrogen and helium
beryllium and boron
potassium and rubidium
**I said D**,
Answer:
D. potassium and rubdium
How many molecules (not moles) of nh3 are produced from 5.81×10−4 g of h2? express your answer numerically as the number of molecules?
which atoms exist as diatomic molecules?
if a solution has a hydronium ion concentration of 1x10^-9 m the solution is
a) acidic and has a pH of 5
b) basic and has a pH of 9
c) basic and has a pH of 5
d) acidic and has a pH of 9
The acidity or alkalinity of a solution depends upon the hydronium ion concentration and hydroxide ion concentration. If a solution has a hydronium ion concentration of 1x10⁻⁹ m the solution is basic. The correct option is B.
What is pH of a solution?The pH of a solution is defined as the negative logarithm to the base 10 of the value of the hydronium ion concentration in moles per litre. The pH scale introduced by Sorensen is more convenient in expressing the hydronium ion concentration of a solution.
The pH can be calculated as:
pH = -log [H₃O⁺]
If the concentration of [H₃O⁺] is less than 10⁻⁷ M, then the solution is found to be basic.
Here pH is:
pH = - log [1 x 10⁻⁹]
= 9
So the pH of the solution is 9.
Thus the correct option is B.
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"what percentage of the solar nebula's mass consisted of elements besides hydrogen and helium gases?"
which of these stars is least likely to be categorized as a supergiant? A. Betelgeuse B. Pollux C. Sirius A D. Sun Reset Submit
Answer: The correct answer is option D.
Explanation: Super-giant stars are the stars which are greater than Sun. They have a mass hundred time greater than Sun and can be thousand times greater than Sun.
The masses of the stars are represented in Solar masses which is the mass of the Sun.
Mass of Betelgeuse = 20 Solar masses
Mass of Pollux = 1.7 Solar masses
Mass of Sirius = 2.02 Solar masses
Mass of Sun = 1 Solar mass.
As, the mass of Sun is the least from the given stars. Hence, it is least considered as a super-giant.
Final answer:
Pollux is the least likely to be categorized as a supergiant since it is an evolved giant star, while Betelgeuse is a known red supergiant, and both Sirius A and the Sun are main-sequence stars.
Explanation:
The star least likely to be categorized as a super giant among the options provided is Pollux. Betelgeuse is a well-known red super giant that is visible near Orion's belt as the bright red star marking the hunter's shoulder. Pollux, in contrast, is classified as an evolved giant star (a red giant), which is a less massive and less luminous stage compared to a super giant. Option B
Sirius A, known for being the brightest star in the sky after the Sun, is a main-sequence star, and also not a super giant. The Sun itself is a main-sequence star, not nearly massive enough to ever become a super giant. Therefore, while neither Pollux, Sirius A, nor the Sun are super giants, Pollux being an evolved giant is the furthest in its life cycle from the super giant category compared to the main-sequence state of Sirius A and the Sun.
MEDAL, please help me understand.
Which best describes the oxidizing agent in this reaction?
Cl2(aq) + 2Brmc003-1.jpg(aq) mc003-2.jpg 2Clmc003-3.jpg(aq) + Br2(aq)
Bromine (Br) is the oxidizing agent because it gains an electron.
Bromine (Br) is the oxidizing agent because it loses an electron.
Chlorine (Cl) is the oxidizing agent because it gains an electron.
Chlorine (Cl) is the oxidizing agent because it loses an electron.,
Answer:
c
Explanation:
At STP, two 5.0-gram solid samples of different ionic compounds have the same density. These solid samples could be dominated by their
The correct answer is option (b). At STP, two 5.0-gram solid samples of different ionic compounds have the same density. These solid samples could be dominated by their crystal structures.
A) Molar masses: The molar mass of a compound refers to the mass of one mole of that substance. While the molar mass affects the mass of the compound, it does not directly determine the density unless the volume occupied by the same mass of different compounds is considered.
B) Crystal structures: The crystal structure refers to the arrangement of ions in a solid. If two ionic compounds have the same density, it is likely that their ions are packed in a similar manner, resulting in the same volume for the same mass. The crystal structure determines how closely the ions are packed together, which directly influences the density.
C) Ionic charges: While ionic charges influence the electrostatic forces between ions, they do not directly determine the density of a solid. The arrangement of ions (crystal structure) has a more direct impact on density than the charges of the ions themselves.
D) **Solubilities**: The solubility of a compound refers to how well it dissolves in a solvent, such as water. This property does not affect the density of the solid form of the compound.
The complete question is:
At STP, two 5.0-gram solid samples of different ionic compounds have the same density. These solid samples could be dominated by their __________.
A) molar masses
B) crystal structures
C) ionic charges
D) solubilities
Which property could be a dominant factor for these solid samples to have the same density?
1. What mass of H2O will be produced if 9.5 g of H2 reacts with 1.2 g of O2?
__ H2 + __ O2 --> __ H2O
2. If 1.85 g of Mg(OH)2 reacts with 3.71 g of HCl, how much MgCl2 is produced? What is the limiting reactant?
__ Mg(OH)2 + __ HCl --> __ MgCl2 + __ H2O
3. What mass of potassium hydroxide is formed when 8.2 g of potassium oxide is added to 1.3 g of water?
__ K2O + __ H2O --> __ KOH
4. What mass of aluminum chloride could be made from 8.1 g of aluminum and 4.2 L of chlorine at STP?
__ Al + __ Cl2 --> __ AlCl3
I know this is a lot of questions but please help and show your work. Thank you.
1) The answer is: mass of water is 1.35 grams.
Balanced chemical reaction: 2H₂ + O₂ → 2H₂O.
m(O₂) = 1.2 g; mass of oxygen.
M(O₂) = 2 · 16 g/mol.
M = 32 g/mol, molar mass of oxygen.
n(O₂) = m(O₂) ÷ M(O₂).
n(O₂) = 1.2 g ÷ 32 g/mol.
n(O₂) = 0.0375 mol; amount of oxygen, limiting reactant.
m(H₂) = 9.5 g; mass of hydrogen.
M(H₂) = 2 g/mol, molar mass of hydrogen.
n(H₂) = m(H₂) ÷ M(H₂).
n(H₂) = 9.5 g ÷ 2 g/mol.
n(H₂) = 4.5 mol; amount of hydrogen.
From chemical reaction: n(O₂) : n(H₂O) = 1 : 2.
n(H₂O) = 0.0375 mol · 2.
n(H₂O) = 0.075 mol; amount of water.
m(H₂O) = n(H₂O) · M(H₂O).
m(H₂O) = 0.075 mol · 18 g/mol.
m(H₂O) = 1.35 g; mass of water.
2) The answer is: 3.05 grams of MgCl₂ is produced, the limiting reactant is Mg(OH)₂.
Balanced chemical reaction: 2HCl + Mg(OH)₂ → MgCl₂ + 2H₂O.
m(Mg(OH)₂) = 1.85 g; mass of magnesium hydroxide
n(Mg(OH)₂) = m(Mg(OH)₂) ÷ M(Mg(OH)₂).
n(Mg(OH)₂) = 1.85 g ÷ 58.32 g/mol.
n(Mg(OH)₂) = 0.032 mol; limiting reactant.
m(HCl) = 3.71 g; mass of hydrochloric acid.
n(HCl) = 3.71 g ÷ 36.46 g/mol.
n(HCl) = 0.102 mol; amount of hydrochloric acid.
From chemical reaction: n(Mg(OH)₂) : n(MgCl₂) = 1 : 1.
n(MgCl₂) =0.032 mol; amount of magnesium chloride.
m(MgCl₂) = n(MgCl₂) · M(MgCl₂).
m(MgCl₂) = 0.032 mol · 95.21 g/mol.
m(MgCl₂) = 3.05 g; mass of magnesium chloride.
3) The answer is: mass of potassium hydroxide is 8.1 grams.
Balanced chemical reaction: K₂O + H₂O → 2KOH.
m(K₂O) = 8.2 g; mass of potassium oxide.
n(K₂O) = m(K₂O) ÷ M(K₂O).
n(K₂O) = 8.2 g ÷ 94.2 g/mol.
n(K₂O) = 0.087 mol; amount of potassium oxide.
m(H₂O) = 1.3 g; mass of water.
n(H₂O) = 1.3 g ÷ 18 g/mol.
n(H₂O) = 0.072 mol; limiting reactant.
From chemical reaction: n(H₂O) : n(KOH) = 1 : 2.
n(KOH) = 2 · 0.072 mol.
n(KOH) = 0.144 mol.
m(KOH) = 0.144 mol · 56.1 g/mol.
m(KOH) = 8.1 g; mass of potassium hydroxide.
4) The answer is: mass of aluminum chloride is 16.66 grams.
Balanced chemical reaction: 2Al + 3Cl₂ → 2AlCl₃.
m(Al) = 8.1 g; mass of aluminium.
n(Al) = m(Al) ÷ M(Al).
n(Al) = 8.1 g ÷ 27 g/mol.
n(Al) = 0.3 mol.
V(Cl₂) = 4.2 L; volume of chlorine.
n(Cl₂) = 4.2 L ÷ 22.4 L/mol.
n(Cl₂) = 0.1875 mol; limiting reactant.
From chemical reaction: n(Cl₂) : n(AlCl₃) = 3 : 2.
n(AlCl₃) = 2 · 0.1875 mol ÷ 3.
n(AlCl₃) = 0.125 mol; amount of aluminium chloride.
m(AlCl₃) = 0.125 mol · 133.34 g/mol.
m(AlCl₃) = 16.66 g; mass of aluminium chloride.