Answer:
(a): The theoretical yield of silicon is 72.33 kg.
(b): The percent yield of the reaction is 91.25 %.
Explanation:
Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.
Excess reagent is defined as the reagent which is left behind after the completion of the reaction.
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] .....(1)
For [tex]SiO_2[/tex]:
Given mass = 155.0 kg = 155000 g (Conversion factor: 1 kg = 1000 g)
Molar mass = 60 g/mol
Putting values in equation 1:
[tex]\text{Moles of }SiO_2=\frac{155000g}{60g/mol}=2583.3mol[/tex]
For carbon:
Given mass = 78.2 kg = 78200 g
Molar mass = 12 g/mol
Putting values in equation 1:
[tex]\text{Moles of carbon}=\frac{78200g}{12g/mol}=6516.67mol[/tex]
The chemical equation for the reaction of silicon dioxide and carbon follows:
[tex]SiO_2+2C\rightarrow Si+2CO[/tex]
By stoichiometry of the reaction:
1 mole of [tex]SiO_2[/tex] reacts with 2 moles of carbon
So, 2583.3 moles of [tex]SiO_2[/tex] will react with = [tex]\frac{2}{1}\times 2583.3=5166.4mol[/tex] of carbon
As the given amount of carbon is more than the required amount. Thus, it is present in excess and is considered as an excess reagent.
Thus, [tex]SiO_2[/tex] is considered a limiting reagent because it limits the formation of the product.
For (a):By stoichiometry of the reaction:
1 mole of [tex]SiO_2[/tex] produces 1 mole of silicon
So, 2583.3 moles of [tex]SiO_2[/tex] will produce = [tex]\frac{1}{1}\times 2583.3=2583.3mol[/tex] of silicon
Since the molar mass of silicon = 28 g/mol
Putting values in equation 1:
[tex]\text{Mass of Si}=2583.3mol\times 28g/mol=72332.4g=72.33 kg[/tex]
Hence, the theoretical yield of silicon is 72.33 kg.
For (b):The percent yield of a reaction is calculated by using an equation:
[tex]\% \text{yield}=\frac{\text{Measured value}}{\text{Theoretical value}}\times 100[/tex] ......(2)
Given values:
Measured value of silicon = 66.0 kg
Theoretical value of silicon = 72.33 kg
Putting values in equation 1:
[tex]\% \text{yield}=\frac{66.0kg}{72.33kg}\times 100\\\\\% \text{yield}=91.25 \%[/tex]
Hence, the percent yield of the reaction is 91.25 %.
why is an alkaline substance dropped into lakes in some countries
Answer:
Lake Treatment
Explanation:
Sulphuric dioxide produced by industries and released into the atmosphere returns as acid rain or sulphuric acid. In lakes impacted by acid rain, such as in Ontario, Canada, the application of alkalis dropped by airplanes can control and neutralize the water's pH level.
5.96 g of ammonia reacts completely according to the following reaction:
2 NH, (g) + Co, (g) → CN,OH, (s) + H20 (1)
(a) What is the theoretical yield of urea (CN,OH,) for this reaction?
(b) If 13.74 g of urea are produced, what is the percent yield for this equation?
please show work, will give brainliest
Explanation:
this explanation may help u to understand:)
The table shows the recipe and the available ingredients for making the maximum possible number of sandwiches.
Making Sandwiches
Recipe for One Sandwich:
2 cheese slices, 1 ham slice, 2 bread slices
Ingredients Available:
12 cheese slices, 10 ham slices, 12 bread slices
If the ingredients represent reactants of a chemical reaction, which of the following represents the leftover reactant?
A. 2 ham slices
B. 4 ham slices
C. 2 cheese slices
D. 4 cheese slices
Answer:
B. 4 ham slices
Explanation:
A chemical reaction involves one or more substances known as reactants combining chemically to give one or more substances known as products.
Reactants in chemical reactions combine in definite mole or mass ratios to give products. Therefore, when one substance is present in excess of what is required to combine with another to form products, that substance is known as the excess reagent. The other substance which is present in a smaller amount and which when used up, the reaction stops is known as the limiting reagent.
From the illustration of the sandwiches in the question, the recipe for one sandwich represents the chemical equation of a reaction. The equation form is given below:
2 cheese slices + 1 ham slice + 2 bread slices ---> 1 sandwich
The ratio of the reactant is 2 : 1 : 2
From the available ingredients, 12 cheese slices, 10 ham slices, 12 bread slices.
12 cheese slices will require 6 ham slices and 12 bread slices to produce 6 sandwiches.
However, since there are 10 ham slices, 4 ham slices will be left over unused. This is the excess or leftover reactant.
Answer:
B. 4 ham slices
Explanation:
Got it right on the test
Please help me complete this, it’s my last chance
Protons: charge: +1 // mass: 1 // location: nucleus
Neutrons: charge: 0// mass: 1 // location: nucleus
Electrons: charge: -1// mass: 0// location: orbitals
Dichlorine monoxide, Cl2O is sometimes used as a powerful chlorinating agent in research. It can be produced by passing chlorine gas over heated mercury (II) oxide according to the following equation: HgO + Cl2 ????HgCl2 + Cl2O What is the percent yield, if the quantity of the reactants is sufficient to produce 0.86g of Cl2O but only 0.71 g is obtained?
Answer:
% yield = 82.5%
Explanation:
HgO + 2Cl₂ → HgCl₂ + Cl₂O
Our reactants are:
HgO and Cl₂Our products are:
HgCl₂ + Cl₂OWe do not have information about moles of reactants, but we do know the theoretical yield and the grams of product, in this case Cl₂O, we have produced.
Percent yield = (Yield produced / Theoretical yield) . 100
Theoretical yield is the mass of product which is produced by sufficent reactant. We replace data:
% yield = (0.71 g/0.86g) . 100 = 82.5%
The percent % yield = 82.5%
The balanced chemical equation will be:
HgO + 2Cl₂ → HgCl₂ + Cl₂O
The reactants participating in this reaction are: HgO and Cl₂
The products so formed are: HgCl₂ + Cl₂O
[tex]\text{ Percent yield} = \frac{\text{Yield produced}}{\text{Theoretical yield}} *100[/tex]
The theoretical yield is the maximum possible mass of a product that can be made in a chemical reaction.
[tex]\text{Percent yield}= \frac{0.71 g}{0.86g} * 100 \\\\\text{Percent yield}= 82.5\%[/tex]
Thus, the percent yield is 82.5%.
Learn more:
brainly.com/question/25996347
A hot air balloon has an air vent that keeps the air pressure inside and outside the same. Allen observes that a hot air balloon rises up when the gas molecules inside it are heated. Which
of the following laws is used to understand the behavior of the gas and why?
a) The high temperature brings the gas molecules closer together according to Charles's law because this law describes how a gas will behave at constant pressure
b) The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
c) The high temperature lowers volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
d) The high temperature ralses volume according to Boyle's law because this law describes how a gas will behave when the number of moles remains constant.
Answer:
B - The high temperature makes the gas molecules spread apart according to Charles's law because this law describes how a gas will behave at constant pressure.
Explanation:
Charle's Law describes the relationship between temperature and volume, where increased temperature leads to increased volume. When volume is increased, that means the gas molecules are more spread apart and have more random motion. Therefore, the answer is B.
The high temperature causes the gas molecules to spread apart according to Charles's law because explain how a gas, behave at constant pressure.
What does Charles law state?The physical principle called Charles' law which states that the volume of a gas equals a constant value many by its temperature as measured on the Kelvin scale.
Volume regaled by a clinched amount of gas is directly proportional to its temperature and pressure if remains steady.
Thus, option "B" is correct, the volume of a gas equals a constant value.
To learn more about Charles law click here:
https://brainly.com/question/14842720
The reaction of iron (III) oxide with carbon monoxide produces iron and carbon dioxide.
Fe,O3(s) + 3CO(g) - 2Fe(s) + 3C0 (9)
If you have 39.5g of Fe2O3, how many grams of CO are required for a complete reaction?
Answer:
21g
Explanation:
no.ofmol fe2o3=39.5/(56×2+16×3)=0.25mol
from equation 1mole fe2o3 react with 3mole co
so,0.25mol fe2o3 react with 0.75mol co
mass of co=0.75×(12+16)=21g
Answer:
Approximately [tex]20.8\; \rm g[/tex].
Explanation:
[tex]\rm Fe_2O_3 \, (s) + 3\; CO\, (g) \to 2\; Fe\, (s) + 3\; CO_2\, (g)[/tex].
Relative atomic mass:
[tex]\rm Fe[/tex]: [tex]55.845[/tex].[tex]\rm C[/tex]: [tex]12.011[/tex].[tex]\rm O[/tex]: [tex]15.999[/tex].Formula mass:
[tex]\begin{aligned}M({\rm Fe_2O_3}) &= 2 \times 55.845 + 3 \times 15.999\\ &= 159.687\; \rm g \cdot mol^{-1}\end{aligned}[/tex].
[tex]\begin{aligned}M({\rm CO}) &= 12.011 + 15.999\\ &= 28.010\; \rm g \cdot mol^{-1}\end{aligned}[/tex].
Number of moles of [tex]\rm Fe_2O_3[/tex] formula units in [tex]39.5\; \rm g[/tex] of this compound:
[tex]\begin{aligned}&n({\rm Fe_2O_3}) \\ &= \frac{m({\rm Fe_2O_3})}{M({\rm Fe_2O_3})} \\ &= \frac{39.5\; \rm g}{159.687\; \rm g \cdot mol^{-1}}\approx 0.247\; \rm mol\end{aligned}[/tex].
Refer to the balanced equation for this reaction.
Coefficient of [tex]\rm Fe_2O_3[/tex]: [tex]1[/tex].Coefficient of [tex]\rm CO[/tex]: [tex]3[/tex].Hence, for every formula unit of [tex]\rm Fe_2O_3[/tex] that this reaction consumes, [tex]3\; \rm mol[/tex] of [tex]\rm CO[/tex] molecules would also need to be consumed. Therefore, if neither reactant is in excess:
[tex]\displaystyle \frac{n({\rm CO})}{n({\rm Fe_2O_3})} = \frac{3}{1} = 3[/tex].
Calculate the number of moles of [tex]\rm CO[/tex] required to react with that [tex]39.5\; \rm g[/tex] of [tex]\rm Fe_2O_3[/tex]:
[tex]\begin{aligned}&n({\rm CO}) \\ &= n({\rm Fe_2O_3}) \cdot \frac{n({\rm CO})}{n({\rm Fe_2O_3})} \\[0.5em] &\approx 0.247\; \rm mol \times 3 \approx 0.742\; \rm mol\end{aligned}[/tex].
Make use of the formula mass of [tex]\!\rm CO[/tex] to find the mass of that [tex]0.742\; \rm mol[/tex] of [tex]\rm CO[/tex] molecules:
[tex]\begin{aligned} m({\rm CO}) &= n({\rm CO}) \cdot M({\rm CO}) \\ &\approx 0.742\; \rm mol \times 28.010\; \rm g \cdot mol^{-1} \\ &\approx 20.8\; \rm g\end{aligned}[/tex].
Calcium has 6 different isotopic forms, listed with their fractional composition values, 40Ca-0.96941; 42Ca-0.00647; 43Ca-0.00135; 44Ca-0.2086 ; 46Ca-0.00004; and 48Ca-0.00187. Identify the most and least abundant isotopes of calcium.
Answer:
The most abundant isotope is ⁴⁰Ca and the least abundant is ⁴⁶Ca
Explanation:
The mass, in percentage, of eah isotope of Calcium is their fractional composition multiplied by 100:
40Ca-0.96941*100 = 96.941% of ⁴⁰Ca
42Ca-0.00647*100 = 0.647% of ⁴²Ca
43Ca-0.0013*100 = 0.13% of ⁴³Ca
44Ca-0.02086*100 = 2.086% ⁴⁴Ca
46Ca-0.00004*100 = 0.004% ⁴⁶Ca
48Ca-0.00187*100 = 0.187% of ⁴⁸Ca
That means the most abundant isotope is ⁴⁰Ca and the least abundant is ⁴⁶Ca
What will be the mass of 2 moles of propane gas?
a 20 grams
b 44 grams
c88 grams
d 30 grams
Answer: 88 grams
Explanation:
Gamma rays have the highest frequency among all common electromagnetic radiations. It means the gamma rays have the highest energy and the longest wavelength
Answer:
yes
Explanation:
cos of high electron transfer
20. What is an irreversible change?
Answer:
A change is called irreversible if it cannot be changed back again. For example you cannot change a cake back into its ingredients again. Irreversible changes are permanent.
Explanation:
Hope this helps!! :))
What are fluids? Why are they so called?
Fluids are liquid and gases. They take the shape of their containers. They are called fluids because of their ability to flow.
What volume of 6.49 MHCl is needed to prepare 2.11 L of 1.07 MHCl? Your answer should have three significant figures.
Answer:
0.348 L
Explanation:
Step 1: Given data
Concentration of the concentrated solution (C₁): 6.49 MVolume of the concentrated solution (V₁): ?Concentration of the dilute solution (C₂): 1.07 MVolume of the dilute solution (V₂): 2.11 LStep 2: Calculate the volume of the concentrated solution
We want to prepare a dilute solution from a concentrated one. We can calculate the volume of the concentrated solution using the dilution rule.
C₁ × V₁ = C₂ × V₂
V₁ = C₂ × V₂ / C₁
V₁ = 1.07 M × 2.11 L / 6.49 M = 0.348 L
how old was the oldest animal fossil
help thx
Answer:
the Rhyniognatha hirsti
Explanation:
at age 400 million years old
Choose the atom that has the largest atomic radius.
a. Cl
b. S
c. Na
d. Si
Answer:
the correct answer is option C. Na
A molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor
a. True
b. False
Answer:
True
Explanation:
Hydrogen bonding is a type of intermolecular interaction that occurs when hydrogen is bonded to a highly electronegative atom.
We define the term ''hydrogen bond donor'' as the molecule that supplies the hydrogen atom in the hydrogen bond.
Hence, it is true that the molecule or ion that donates the hydrogen in a hydrogen bond is a hydrogen bond donor
Refer to your completed Table 1d of the recitation guide of ionic compound naming rules to determine whether this statement is true or false. A Roman numeral in a compound name tells you how many of that ion appear in the formula. Select one: True False
Answer:
False
Explanation:
Roman numerals are seen in the names of several compounds. They often appear immediately after the name of central atom in the molecule.
These Roman numerals are used to depict the oxidation state of the central atom in the molecule and not to show how many of that ion appear in the formula.
For instance, in carbon IV oxide, the Roman numeral IV shows that the central atom in the compound-carbon is in the +4 oxidation state.
what elements don't form bonds
Answer:
Noble gases are a set of elements in the periodic table because they don't naturally bond with other elements. *Examples ...Helium; Neon; Radon; Xenon; Argon etc
Explanation:
theyre noble gases.
A solution containing 1.22 g of a diprotic acid H2CH2O4 (malonic acid)
was titrated with 45.5 mL of NaOH to reach the second equivalence
point. What is the concentration of the NaOH solution? (MW_malonic
acid = 104.06 g/mol)
Answer:
0.515 M
Explanation:
The reaction that takes place is:
H₂CH₂O₄ + 2NaOH → Na₂CH₂O₄ + 2H₂OFirst we convert 1.22 g of malonic acid into moles, using its molar mass:
1.22 g ÷ 104.06 g/mol = 0.01172 molThen we convert 0.01172 malonic acid moles into NaOH moles, using the stoichiometric coefficients of the balanced reaction:
0.01172 mol H₂CH₂O₄ * [tex]\frac{2molNaOH}{1molH_2CH_2O_4}[/tex] = 0.02344 mol NaOHFinally we calculate the concentration of the NaOH solution, using the number of moles and given volume:
Converting 45.5 mL ⇒ 45.5/1000 = 0.0455 L
0.02344 mol / 0.0455 L = 0.515 MCollision theory states that as molecules or ions bump into each other, a reaction will only occur if the collision has the correct amount of energy and impact is at the right angle and location. Describe how collision theory helps predict how temperature, pressure, and concentration impact reaction rates. Question 5 of 11 Collision theory states that as molecules or ions bump into each other, a reaction will only occur if the collision has the correct amount of energy and impact is at the right angle and location. Describe how collision theory helps predict how temperature, pressure, and concentration impact reaction rates. As temperature increases, the number of collisions _______ and the energy of the collisions _______.
Answer: As temperature increases, the number of collisions increases and the energy of the collisions increases.
Explanation:
According to collision theory, for a reaction to take place it is necessary to have collisions between the reacting species or atoms.
A collision will only be effective if species coming together have a certain minimum value of internal energy equal to the activation energy of the reaction.
More is the number of collisions taking place in a chemical reaction more will be the kinetic energy of its molecules. As kinetic energy is the energy acquired due to motion of atoms or a substance.
Also, collisions increases with increase in temperature as:
[tex]K.E = \frac{3}{2}kT[/tex]
Kinetic energy is directly proportional to temperature. So, more is the temperature more will be energy of molecules.
Thus, we can conclude that as temperature increases, the number of collisions increases and the energy of the collisions increases.
12. Which formula shows a substance that is not molecular?
H₂
H2O
н
CO2
Answer:
the answer is H ..............
Having enough folic acid in your system by the early weeks of pregnancy is critical to prevent spina bifida.
Answer:
Yes.
Explanation:
Yes, enough folic acid in the body by the early weeks of pregnancy helps to prevent spina bifida. The body of woman uses folate during the pregnancy which produces red and white blood cells that help your baby to grow. Folate also lowers the risk of neural tube defect (NTD) in the unborn baby. Neural tube defect (NTDs) are the serious birth defects that greatly affect the spinal cord, brain and skull of the baby.
When using vacuum filtration to separate a dissolved solid from an undissolved solid, what techniques should you use to ensure a quantitative separation
Answer: See explanation
Explanation:
Vacuum filtration is referred to as a fast filtration technique that is used in the separation of solids from liquids. It is also used to collect a desired solid. It basically uses a side-arm flask and a Buchner funnel.
Based on the question, the techniques that should be used to ensure a quantitative separation goes thus:
• Wet the filter paper before the mixture is poured into the filter funnel.
• Then, carefully rinse the flask with a little amount of water into the filter funnel.
• After that, the solid on the filter paper should be washed the with a small amount of water.
• Finally, Dry the solid on the filter paper when the separation is done.
can yall please help im very slow
Answer:
turtle
Explanation:
they are slow and they take there time
The reaction of bromine gas with chlorine gas, shown here, has a Keq value of 7.20 at 200°C. If a closed vessel was charged with the two reactants, each at an initial concentration of 0.200 M, but with no initial concentration of BrCl, what would be the equilibrium concentration of Br2, Cl2 and BrCl(g)?
Br2(g) + Cl2(g) ↔ 2BrCl(g) K = 7.20
Answer:
[tex][Cl_2]=[Br_2]=0.856M[/tex]
[tex][BrCl]=0.229M[/tex]
Explanation:
Hello there!
In this case, for this chemical equilibrium problem, it turns out possible for us to solve for the equilibrium concentrations by firstly setting up the equilibrium expression:
[tex]Keq=\frac{[BrCl]^2}{[Cl_2][Br_2]}[/tex]
Thus, by plugging in an ICE chart, in terms of x (reaction extent), we can write:
[tex]7.20=\frac{(2x)^2}{(0.200-x)^2}[/tex]
And could be solved for x as follows:
[tex]\sqrt{7.20} =\sqrt{\frac{(2x)^2}{(0.200-x)^2} } \\\\2.68=\frac{2x}{0.200-x} \\\\x=0.1146M[/tex]
Therefore, the equilibrium concentrations turn out to be:
[tex][Cl_2]=[Br_2]=0.200M-0.1146M=0.856M[/tex]
[tex][BrCl]=2*0.1146M=0.229M[/tex]
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Answer:
?
Explanation:
A small coffee cup calorimeter contains 28.0 g of H2O at 19.73 oC. A 2.05 g sample of a metal alloy is heated to 98.88 oC and then placed in the water. The contents of the calorimeter come to a temperature of 21.23 oC. What is the specific heat of lead
Answer:
1.104 J/g°C
Explanation:
Using Q = m × c × ∆T
Where;
m = mass of substance (g)
c = specific hear capacity (J/g°C)
∆T = change in temperature (°C)
For a colorimeter,
Q(water) = - Q(metal)
m. c. ∆T (water) = - m. c. ∆T (metal)
According to the information provided;
For water:
m = 28.0g
c = 4.184 J/g°C
∆T = (21.23 - 19.73°C)
For the metal:
m = 2.05g
c = ?
∆T = (21.23 - 98.88°C)
m. c. ∆T (water) = - m. c. ∆T (metal)
[28 × 4.184 × (21.23 - 19.73°C)] = -[2.05 × c × (21.23 - 98.88°C)]
[117.152 × 1.5] = -[2.05 × c × (-77.65)]
175.728 = -[-159.1825c]
175.728 = 159.1825c
c = 175.728 ÷ 159.1825
c = 1.104
c = 1.104 J/g°C
someone answer please
Answer:
A
Explanation:
Density of a substance can be used as unit factor for conversion between mass and volume: then the If 20 g of gold (density 19.3 g/cm), the corresponding volume that gold will occupy is
Answer:
density = d = 19.3g/cm^3
Mass of gold = m= 20g
now
we know,
density = mass / volume
or volume = mass/ density
volume = 20/19.3 = 1.036cm^3
Explanation:
I need help please ASAP
