Given the chart of bond energies, calculate the enthalpy change for the reaction below. Show all work to receive full credit.
Answers
The enthalpy change of the reaction -
CH₄ + 2O₂ = CO₂ + 2H₂O is -808kJ/mol.
Enthalpy is the measurement of energy in a thermodynamic system. The quantity of enthalpy equals to the total content of heat of a system, equivalent to the system’s internal energy plus the product of volume and pressure.
For a process taking place at constant pressure, the enthalpy change is equal to the heat absorbed or evolved. If the enthalpy change is positive, heat is absorbed and the reaction is endothermic. If the enthalpy change is negative, heat is evolved and the reaction is termed exothermic.
Given,
Enthalpy change = Sum of bond energies of reactants - sum of bond energies of products
= (4 × C-H) + (2 × O = O) - (2 × C = O) + (4 × O-H)
= [( 4 × 413 ) + ( 2 × 495 )] - [( 2 × 799 ) + ( 4 × 463 )]
= (1652 + 990) - (1598 + 1852)
= 2642 - 3450
= -808 kJ/ mol
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Related Questions
A 100 cc bottle of Amoxicillin 125 oral suspension requires addition of 61 ml of Purified Water to make 100 cc. What is the powder volume
Answers
A 100 cc bottle of Amoxicillin 125 oral suspension requires addition of 61 ml of Purified Water to make 100 cc. The powder volume is 76.25.
How do you calculate powder volume ?To calculate the powder volume use the expression
[tex]\frac{H}{Q} = \frac{D}{X}[/tex]
where,
H = Dose on hand
Q = Quantity on hand
D = Desired dose
X = Quantity desired
Now put the values in above expression we get
[tex]\frac{H}{Q} = \frac{D}{X}[/tex]
[tex]\frac{100}{61} = \frac{125}{X}[/tex]
[tex]X = \frac{125 \times 61}{100}[/tex]
X = 76.25
Thus from the above conclusion we can say that A 100 cc bottle of Amoxicillin 125 oral suspension requires addition of 61 ml of Purified Water to make 100 cc. The powder volume is 76.25.
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1. Determine the molecular formula of an oxide of iron in which the mass of iron and oxygen are 69.9% and 30% respectively given that the molar mass of the oxide 159.898/mol, find the empirical and molecular formula.
2. a crystalline salt when heated becomes anhydrous and loses 51.2% of its weight the anhydrous salt analysis gave the percent composition as magnesium is equal to 20.0% and sulphur is equal to 26.66% and oxygen is equal to 53.33%.
3. In three moles of Ethane calculate the following
1. calculate number of carbon atoms.
2. number of moles of hydrogen atoms
3. number of molecules of Ethane.
Answers
1a. The empirical formula of the compound is Fe₂O₃
1b. The molecular formula of the compound is Fe₂O₃
2a. The molecular formula of the anhydrous salt is MgSO₄
2b. The formula of the crystalline salt is MgSO₄.7H₂O
3i. The number of mole of carbon atoms in the compound is 6 moles
3ii. The number of mole of hydrogen atoms in the compound is 18 moles
3iii. The number of molecules in 3 moles of ethane is 1.806×10²⁴ molecules
1a. How to determine the empirical formulaFe = 69.9%O = 30%Empirical formula =?Divide by their molar mass
Fe = 69.9 / 56 = 1.248
O = 30 / 16 = 1.875
Divide by the smallest
Fe = 1.248 / 1.248 = 1
O = 1.875 / 1.248 = 3/2
Multiply by 2 to express in whole number
Fe = 1 × 2 = 2
O = 3/2 × 2 = 3
Thus, the empirical formula of the compound is Fe₂O₃
1b. How to determine the molecular formulaEmpirical formula = Fe₂O₃Molar mass of compound = 159.89 g/molMolecular formula = ?Molecular formula = empirical × n = molar mass
[Fe₂O₃]n = 159.89
[(56×2) + (16×3)]n = 159.89
160n = 159.89
n = 159.89 / 160
n = 1
Molecular formula = [Fe₂O₃]n
Molecular formula = [Fe₂O₃] × 1
Molecular formula = Fe₂O₃
2a. How to determine the molecual formula of the anhydrous saltWe'll begin by calculating the empirical formula
Mg = 20.0% S = 26.66% O = 53.33%Empirical formula =?Divide by their molar mass
Mg = 20.0 / 24 = 0.83
S = 26.66 / 32 = 0.83
O = 53.33 / 16 = 3.33
Divide by the smallest
Mg = 0.83 / 0.83 = 1
S = 0.83 / 0.83 = 1
O = 3.33 / 0.83 = 4
Thus, the empirical formula of the anhydrous salt is MgSO₄
The molecular formula of the anhydrous salt can be obtained as follow:
Empirical formula = MgSO₄Molar mass of compound = 120 g/molMolecular formula = ?Molecular formula = empirical × n = molar mass
[MgSO₄]n = 120
[24 + 32 + (16×4)]n = 159.89
120n = 120
n = 120 / 120
n = 1
Molecular formula = [MgSO₄]n
Molecular formula = [MgSO₄] × 1
Molecular formula = MgSO₄
2b. How to determine the formula of the crystalline saltWater (H₂O) = 51.2%Anhydrous salt (MgSO₄) = 100 - 51.2 = 48.8%Formula of crystalline salt =?Divide by their molar mass
MgSO₄ = 48.8 / 120 = 0.4
H₂O = 51.2 / 18 = 2.8
Divide by the smallest
MgSO₄ = 0.4 / 0.4 = 1
H₂O = 2.8 / 0.4 = 7
Thus, the formula of the crystalline salt is MgSO₄.7H₂O
3i. How to determine the mole of carbon atoms in 3 moles of C₂H₆1 mole of C₂H₆ contains 2 moles of carbon atoms.
Therefore,
3 moles of C₂H₆ will contain = 3 × 2 = 6 moles of carbon atoms
3ii. How to determine the mole of hydrogen atoms in 3 moles of C₂H₆1 mole of C₂H₆ contains 6 moles of hydrogen atoms.
Therefore,
3 moles of C₂H₆ will contain = 3 × 6 = 18 moles of hydrogen atoms
3iii. How to determine the number of moleculesFrom Avogadro's hypothesis,
1 mole of ethane = 6.02×10²³ molecules
Therefore,
3 moles of ethane = 3 × 6.02×10²³ molecules
3 moles of ethane = 1.806×10²⁴ molecules
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Complete question
2. A crystalline salt when heated becomes anhydrous and loses 51.2% of its weight the anhydrous salt analysis gave the percent composition as magnesium is equal to 20.0% and sulphur is equal to 26.66% and oxygen is equal to 53.33%. Ccalculate the molecular formula of the anhydrous and the crystalline salt. The molecular weight of the anhydrous salt is 120
PLEASE I NEED HELP ASAP!!!!
1.)Alex reacts 40.0 grams of substance X with 850 mL of 1.0 mol/L solution of hydrochloric acid. What is the maximum mass of carbon dioxide gas that could be obtained from this reaction?
2.)Jess reacts 25.0 grams of substance X with 40.0 mL of 2.0 mol/L of sodium hydroxide solution. The reaction yielded 2.5 grams of calcium hydroxide. Calculate the theoretical yield of calcium hydroxide and %Yield for the reaction.
Answers
The percent yield of the calcium hydroxide is 84.5%.
What is stoichiometry?Stoichiometry enables us to obtain the mass of a substance form the equation of the reaction.
The equation of the reaction is;
CaCO3 + 2HCl -----> CaCl2 + CO2 + H2O
Number of moles of X = 40.0 grams/100 g/mol = 0.4 moles
Number of moles of HCl = 850/1000 * 1 M = 0.85 moles
If 1 mole of CaCO3 reacts with 2 moles of HCl
0.4 moles of CaCO3 reacts with 0.4 moles * 2 moles/1 mole
= 0.8 moles of HCl
Hence X is the limiting reactant.
The reaction is 1:1 then the amount of CO2 produced is 0.4 moles
Mass of CO2 = 0.4 CO2 * 44 g/mol = 17.6 g
2) The reaction equation is; 2NaOH + CaCO3 ---> Ca(OH)2 + Na2CO3
Number of moles of X = 25.0 grams/100 g/mol = 0.25 moles
Number of moles of NaOH= 40/1000 L * 2 M = 0.08 moles
If 1 mole of X reacts with 2 moles of NaOH
0.25 moles reacts with 0.25 moles * 2 moles /1 mole
= 0.5 moles
NaOH is the limiting reactant
2 moles of NaOH produces 1 mole of CO2
0.08 moles of NaOH produces 0.08 moles * 1 mole/2 moles
= 0.04 moles of CO2
Theoretical yield of CO2 = 0.04 moles of CO2 * 74 g/mol = 2.96 g
Percent yield = 2.5 g/ 2.96 g * 100
= 84.5%
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Which solution could be used to precipitate the calcium ion form a water sample?
Answers
Calcium carbonate ([tex]CaCO_{3}[/tex]), an insoluble precipitate that could be removed from water by filtration, is created when the calcium ion in hard water bonds with the carbonate ion.
Precipitates may be ionic solids that are insoluble and result from reactions between certain cations as well as anions in water. A precipitate's formation could be influenced by a variety of circumstances.
When calcium atoms gain or lose electrons, they change their charge but also reactivity, forming calcium ions.
Therefore, Calcium carbonate ([tex]CaCO_{3}[/tex]), could be used to precipitate the calcium ion form a water sample
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A sample of neon gas in a bulb is at 149.05 °C and 349.84 kPa. If the pressure drops
to 103.45 kPa, what is the new temperature (in °C)? Provide your answer to two
decimals.
Answers
The new temperature (in °C) of the gas, given the data is –148.20 °C
Data obtained from the question Initial temperature (T₁) = 149.05 °C = 149.05 + 273 = 422.05 KInitial pressure (P₁) = 349.84 KPa Volume = constant New pressure (P₂) = 103.45 KPaNew temperature (T₂) =? How to determine the new temperatureThe new temperature of the gas can be obtained by using the combined gas equation as illustrated below:
P₁V₁ / T₁ = P₂V₂ / T₂
Since the volume is constant, we have:
P₁ / T₁ = P₂ / T₂
349.84 / 422.05 = 103.45 / T₂
Cross multiply
349.84 × T₂ = 103.45 × 422.05
Divide both side by 349.84
T₂ = (103.45 × 422.05) / 349.84
T₂ = 124.80 K
Subtract 273 from 124.80 K to express in degree celsius
T₂ = 124.80 – 273
T₂ = –148.20 °C
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Which of the following can easily form an ionic bond with a cation?
Sr
Ne
NH4+
PO43–
Answers
PO43- can form an ionic bond with a cation.
The chemical species which can easily form an ionic bond with a cation will be.
The definition of an ionic bond is a chemical bond that is formed between two ions that have opposite charges.
An Ionic bond is formed when one atom gives up one or more electrons to another atom.
These bonds can easily form between a pair of atoms or between molecules. This kind of bonding is most widely seen in bonds present in salts.
Compared to other options given, is the best option as the total number of 32 valence electrons, is the highest among the given choices. Its tendency to form ionic bonds with the other cation is much higher as compared to others.
P has 5 electrons which combine with 4 O atoms which have 6 lone pairs and a -3 charge on it, which means it is accepting 3 electrons so it will be (+3), so total valence electrons will be 5 + 6 (4) + 3 = 32.
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Which compound has the lowest melting point?
CaCl2
K2Cr2O7
C6H12O6
K2O
Answers
Answer:
[tex]K2O[/tex]
Explanation:
If you use a melting point periodic table there is a listing of all the elements and their melting point.
Potassium (K) has a melting point of 63.25 degrees Celsius and oxygen (O) has a melting point of -218 degrees Celsius. Therefore, if you add those two values up
[tex](63.25x2)+-218 = -91.5 Degrees Celsius[/tex]
All the other compounds do not reach negatives.
The protein--iron compound that has the bonding capabilities for the transport of oxygen and carbon dioxide is:
Answers
It is hemoglobin.
What is hemoglobin and its composition?In the red blood cells (erythrocytes) of vertebrates, hemoglobin, an iron-containing protein, transports oxygen from the lungs to the body's tissues and organs and returns carbon dioxide to the lungs. In a complete blood cell (CBC) test, the amount of hemoglobin in the blood is often measured.
A globin group is surrounded by four heme groups, which together form a tetrahedral shape in each hemoglobin molecule. Heme is an organic complex known as a porphyrin that has an iron atom linked to it. Heme makes up only 4% of the weight of the molecule. As the blood circulates between the lungs and the tissues, the iron atom is what holds oxygen in place. Each hemoglobin molecule contains four iron atoms, and as a result, it has the capacity to bind four oxygen molecules. Two linked pairs of polypeptide chains make up globin.
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Provide the organometallic reagent that is needed to perform the transformation shown below. The reagent should be formatted as LiR or BrMgR, where R is an alkyl group written as a Condensed Formula. Do not use subscripts.
Answers
The correct answer is [tex]LiCH_{3}CH(CH_{3} )CH_{3}[/tex] .
Organometallic reagentOrganometallic chemistry is the study of organometallic compounds, which are substances that contain at least one chemical bond between a carbon atom from an organic molecule and a metal. These substances include alkali, alkaline earth, and transition metals, as well as metalloids like boron, silicon, and selenium. In addition to links to organyl fragments or molecules, bonds to 'inorganic' carbon, such as those to carbon monoxide (metal carbonyls), cyanide, or carbide, are also typically regarded as organometallic. Although they are not strictly speaking organometallic compounds, some similar compounds, such as transition metal hydrides and metal phosphine complexes, are frequently included in discussions of such substances. The phrase "metalorganic compound," which is comparable but different, describes molecules that contain metals but do not have direct metal-carbon bonds but do have organic ligands.
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Predict the nature of the indicated
covalent bond.
H
H
polar
H-C
H
-C-H
H
non-poiar
Answers
Answer:
Non-polar
Explanation:
Non-polar bonds occur when the electrons in a covalent bond are equally shared between the two atoms.
The indicated bond is most likely non-polar because the two atoms are identical (both carbons). In addition, these two carbons are balanced (their other bonds are identical). This means there is no reason for the electrons in the bond to be pulled in any particular direction.
At the stoichiometric (equivalence) point in a titration of benzoic acid with naoh(aq) shown by equation 3, the ph is:_______
Answers
Benzoic acid is one of the weakest acid for titration. The pH of the salt solution generated is the pH greater than 7( >7 ) at the equivalence point in any titration.
The benzoate anion, combines with water to create OH- and undissociated benzoic acid. This reaction is stronger than OH-. As a result of the hydroxide ions generated by this reaction, the final solution has a pH greater than 7. Hydrolysis is the term for an ion's reaction with water, such as the benzoate ion.
What is titration?A titration is a method for figuring out the concentration of an unknown solution by using a solution with known concentration.Until the reaction is finished, the titrant (the known solution) is typically added from a buret to a known volume of the analyte (the unknown solution).The concentration of the unknown can be determined by knowing the amount of titrant that was added. An indicator is frequently used to indicate the reaction's endpoint or end of the reaction.Know more about titration numerical https://brainly.com/question/14501686
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Determine the mass, in grams, of 0.350 moles of s (1 mol of s has a mass of 32.07 g).
Answers
Answer:
11.22 gm
Explanation:
32.07 gm / mole * .350 mole = 11.22 gm
The mass of 0.350 moles of Sulphur is equal to 11.22 g.
What is a mole?A mole is a standard unit which is used to calculate the huge number of quantities of atoms, molecules, ions, or other particular particles. The mass of the one mole of any element is called atomic mass and that of any compound is called molar mass.
The number of units present in one mole was found to be equal to 6.023 × 10 ²³ which is known as Avogadro’s constant or Avogadro’s number.
Given, the number of moles of sulphur = 0.350 moles
The mass of one mole of sulphur = 32.07 g
Then, the mass of 0.350 moles of Sulphur = 0.350 × 32.07
The mass of 0.350 moles of Sulphur (S) = 11.22 g
Therefore, 11.22 grams is the mass of 0.350 moles of Sulphur (S).
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Draw the major 1,2- and 1,4-addition products that form as a result of the following reaction between one equivalent each of 2,4-hexadiene and HBr.
Answers
The major 1,2- and 1,4-addition products are 4-Bromo-2-hexene and 2-Bromo-2-hexene.
What is Markovnikov Rule ?
Markovnikov rule explains that in addition reaction of alkene react with a hydrogen halide. The hydrogen atom is attached to the carbon atom that is already bonded to the greatest number of hydrogen.
What is Addition Reaction ?An addition reaction is an organic reaction occur when two or more molecules combine to form a larger molecule without the loss of any atoms present in reactant.
Thus from the above conclusion we can say that The major 1,2- and 1,4-addition products are 4-Bromo-2-hexene and 2-Bromo-2-hexene.
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Draw an atomic structure of Sodium (Na). What are sub-atomic particles?
Answers
Sodium represents by the (Na).
_____ in carbon dioxide in your red blood cells, which causes _____ in ph, causes your breathing to speed up.
Answers
Increase in carbon dioxide in your red blood cells, which causes a drop in pH, causes your breathing to speed up.
The presence of carbon dioxide in red blood cell will lower the pH because carbon dioxide combines with water to form [tex]H^{+}[/tex] and [tex]HCO_{3} ^{-}[/tex] .
About 70% of Carbon dioxide transported as bicarbonate ion in the plasma of the red blood cells .When carbon dioxide diffuses across the cell membrane of erythrocyte then it reacts with water to form carbonic acid.This carbonic acid breaks into bicarbonate ion and proton in the presence of carbonic anhydrase . this is because it is very unstable.This hydrogen ions binds to the hemoglobin and which results in initiation of bohr effect .So, as concentration of hydrogen ions increases pH of the blood decreases.learn about carbonic acid
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please help me with this question
Answers
From the calculation, the concentration in parts per billion is 6 ppb.
What is ppb?The term ppb refers to the concentration of a substance in parts per billion. We obtain the ppb using the formula;
Mass of solute/ Mass of solution * 10^9
Now, 1L = 1000cm^3 = 1000 g
The concertation in ppb = 6 * 10^-6 g/1000 g * 10^9
= 6 ppb
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The main acid in the stomach is hydrochloric acid (HCl). Which chemical equations show a reaction that occurs when someone takes an antacid
Answers
Answer:
Mg(OH)2(s) + 2HCl(aq) => MgCl2(aq) + 2HCl(l)
Explanation:
The reaction that occurs in the stomach when one takes an antacid {Mg(OH)2} is termed as Neutralization reaction as it reacts with hydrochloric acid to form magnesium hydroxide and water.
The equation of reaction:
Mg(OH)2(s) + 2HCl(aq) => MgCl2(aq) + 2HCl(l)
The mass of solute per 100 mL of solution is abbreviated as (m/v). Mass is not technically the same thing as weight, but the abbreviation (w/v) is also common. How many grams of sucrose are needed to make 655 mL of a 40.0% (w/v) sucrose solution
Answers
The mass of solute per 100 mL of solution is abbreviated as (m/v). Mass is not technically the same thing as weight, but the abbreviation (w/v) is also common. 262 grams of sucrose are needed to make 655 mL of a 40.0% (w/v) sucrose solution
Define SoluteA solute is a material that dissolves in a solution. The amount of solvent present in fluid solutions is greater than the amount of solute. The two most common examples of solutions in daily life are salt and water. Salt is the solute because it dissolves in water.
forms of ratios for product concentration or yield:-w/v:- Weight by volume or weight per volume are the terms used. Any solid compound's concentration in a liquid can be calculated using it. It is measurable in gm/ml.Weight by weight ratio is referred to as w/w.It is employed to determine the final yield of the compound obtained from the starting compound. as in —mg/—gm.It provides the real yield of the substance or item.
Volume/volume. It is used to specify a liquid's composition or percent in a liquid compound.using w/v we can calculate the weight of sucrose:-
40.0% means 40 g sucrose/ 100 g solution
40.0g sucrose x (655/100)=grams of sucrose
262 grams of sucrose are needed to make 655 mL of a 40.0% (w/v) sucrose solution.
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Given the balanced equation: 2KClO3 --> 2KCl 3O2 What type of reaction is represented by this equation
Answers
The correct option is (2) decomposition.
In the balanced equation 2KClO3==> 2KCl + 3O2, as there is a reduction of oxygen therefore it is decomposition reaction.
What is decomposition reaction?A chemical reaction that results in the breakdown of one reactant into two or more reactants is known as a decomposition reaction.
The general equation for decomposition is-
AB -> A + B
Where A & B are now the product molecules and AB is the parent (reactant) molecule.
Some key features of the decomposition reaction are-
A combination reaction is the opposite of the a decomposition reaction. In such reactions, a single product is created form two or even more reactants.Decomposition processes are not always endothermic. Both endothermic and exothermic reactions can take place during decomposition. This one is more typical than the former, though.Extraction of metal from their ores is a significant use of decomposition processes. For instance, by putting calamine through a breakdown reaction, zinc can be extracted. The same process can be used to make sodium form sodium chloride (NaCl).A type of decomposition reaction known to be a double decomposition reaction involves the exchange of positive and negative ions between two constituent reactants to create two new molecules.To know more about decomposition reaction, here
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The complete question is-
Given the balanced equation:
2KClO3==> 2KCl + 3O2
Which type of reaction is represented by this equation?
(1) synthesis
(2) decomposition
(3) single replacement
(4) double replacement
How many sucrose molecules are in 3.0 moles of sucrose?
Answers
Answer: No of molecule of sucrose = 1.806 X 10^24
Explanation:
No. of molecules = No. of moles X NA
No. of molecule of sucrose = 3 moles X 6.02 X 10^23
No of molecule of sucrose =18.06 X 10^23
No of molecule of sucrose =1.806 X 10^24
Answer:
1.80 × 10²⁴ Molecules of Sucrose
HELP PLEASE!!!!!
2. To test for the presence of substance X, a lab assistant,
Alex, treats a sample of the material with hydrochloric acid.
Bubbles of carbon dioxide gas are observed and collected
during the test reaction. Write a balanced chemical equation
for the reaction.
3. Another lab assistant, Jess, disagrees with Alex, and treats
a sample of substance X with sodium hydroxide. One of the
products of this reaction is a compound called milk of lime
(found to be only slightly soluble in water). Write a balanced
chemical equation and identify the type of reaction taking
place.
4. Which lab assistant is performing a valid test for substance
X? Explain your answer, including a prediction of what would
be observed during a positive test. HINT: Research what is the
valid test for substance X. At this point you should know the
identity of substance X (you found it in Question #1).
62%
Answers
(2.) A lab assistant Alex test for the presence of X, the balanced chemical equation is CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O. (3.) Another lab assistant perform the test, the balanced chemical equation is CaCO₃ + 2NaOH → Ca(OH)₂ + Na₂CO₃. (4.) The Substance X is Calcium carbonate.
What is Balanced Chemical Equation ?The balanced chemical equation is the equation in which the number of atoms on the reactant side is equal to the number of atoms on the product side in an equation.
(2.) To test for the presence of substance X, a lab assistant, Alex, treats a sample of the material with hydrochloric acid. Bubbles of carbon dioxide gas are observed and collected during the test reaction.
The balanced chemical equation is
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
(3.) Another lab assistant, Jess, disagrees with Alex, and treats a sample of substance X with sodium hydroxide. One of the products of this reaction is a compound called milk of lime (found to be only slightly soluble in water).
The balanced chemical equation is
CaCO₃ + 2NaOH Ca(OH)₂ + Na₂CO₃
The type of reaction is Double displacement reaction
(4.) The lab assistant Alex perform the valid test for substance X because it gives effervescence of bubbles. The substance X is calcium carbonate. When calcium carbonate react with dilute HCl then carbon dioxide gas bubbles is present in it.
Thus from the above conclusion we can say that (2.) A lab assistant Alex test for the presence of X, the balanced chemical equation is CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O. (3.) Another lab assistant perform the test, the balanced chemical equation is CaCO₃ + 2NaOH → Ca(OH)₂ + Na₂CO₃. (4.) The Substance X is Calcium carbonate.
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please help me with this question, and if u can do it on paper
Answers
1. O2 is the limiting reagent
2. Excess NH3 = 0.102 moles
3. 0.088 mol of NO is formed
4. 2.376 grams of H2O is formed
Stoichiometric problemFrom the equation: [tex]4NH_3 + 5O_2 --- > 4NO + 6H_2O[/tex]
Mole ratio of NH3 and O2 = 4:5
Mole of 3.25 g NH3 = 3.25/17 = 0.19 mol
Mole of 3.50 g O2 = 3.5/32 = 0.11 mol
Equivalent mole of O2 from NH3 = 5/4 x 0.19 = 0.24 mol
Equivalent mole of NH3 from O2 = 4/5 x 0.11 = 0.088 mol
Thus, O2 is the limiting reagent.
Excess NH3 = 0.19 - 0.088 = 0.102 moles
Mole ratio of O2 and NO = 5:4
Equivalent mole of NO = 4/5 x 0.11 = 0.088 mol
Mole ratio of O2 and H2O = 5:6
Equivalent mole of H2O = 6/5 x 0.11 = 0.132 mol
Mass of 0.132 mol H2O = 0.132 x 18 = 2.376 grams
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N analyst prepared a sucrose solution by weighing 1kg of water and add 1.5kg sucrose.estimate the concentration of the resultant solution in (i) mass percent (ii) degree brix
Answers
The concentration of the solution in mass percent is 60%.
What is the mass percent?The concentration of a substance can be expressed in mass percent. This refers to the percentage of the solute that is contained in the solution.
Thus we can write;
Mass percent = Mass of solute/ Mass of solution * 100/1
Mass percent = 1.5kg/1.5kg + 1 Kg * 100/1
Mass percent = 60%
Hence, the concentration of the solution in mass percent is 60%.
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which of the following pairs would have a larger size? explain your answer.
K or K^(+)
Br or Br^(-)
Answers
Answer:
k ion is the largest size of the radius it is always smaller compared to the parent ion
Explanation:
Relative humidity is described as: Group of answer choices a basically unused concept when it comes to weather topics. the amount of water vapor in the air at a given temperature expressed as a percentage of the water vapor capacity of the air. the amount of water vapor in the air compared to the normal amount. the amount of moisture in the air relative to your own sensible feelings.
Answers
Correct answer:
The relative humidity is best described as the amount of water vapor in the air at a given temperature expressed as a percentage of the water vapor capacity of the air.
What is relative humidity?
The ratio of the current absolute humidity to the highest absolute humidity is known as relative humidity (which depends on the current air temperature).
Water vapor is also measured by relative humidity, which is stated as a percentage but RELATIVE to the air's temperature. In other words, it is a comparison between the amount of water vapor that is actually present in the air and the maximum amount of vapor that is possible for the air at the current temperature.
With the same quantity of absolute/specific humidity, air will have a HIGHER relative humidity if it is cooler and a LOWER relative humidity if it is warmer because warm air may contain more water vapor (moisture) than cold air. The actual amount of moisture (absolute humidity) in the air is what we "feel" outside.
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Two-thirds of a bone's weight is composed of calcium phosphate which interacts with calcium hydroxide to form crystals of __________.
Answers
Two-thirds of a bone's weight is composed of calcium phosphate which interacts with calcium hydroxide to form crystals of hydroxyapatite
The two component of bones are 33% organic matter and 67% inorganic matter( Calcium phosphate and hydroxyapatite crystal).Calcium phosphate make up almost 2/3 of the bone's weight.Collagen fibers make up almost 1/3 of the bone's weight.The calcium phosphate interacts with calcium hydroxide to form crystals of hydroxyapatite, whose molecular formula is [tex]Ca_{10} (PO_{4} )_{6} (OH)_{2}[/tex]
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Blank + BaCl2 = BaSO4 + 2NaCl
How to complete this chemical reaction so that it is a Double displacement reaction
Answers
The blank is filled by Na₂SO₄, and the complete equation for the double displacement reaction is:
Na₂SO₄ + BaCl₂ = BaSO₄ + 2 NaCl
What is a double displacement reaction?It is a reaction in which both reactants exchange anions and cations.
Let's consider the following incomplete double displacement reaction.
_____ + BaCl₂ = BaSO₄ + 2 NaCl
If we compare the left and right sides, we can see that the missing ions in the left side are Na⁺ and SO₄²⁻. Thus, the missing compound is Na₂SO₄. The complete equation is:
Na₂SO₄ + BaCl₂ = BaSO₄ + 2 NaCl
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A short chain of monomer liquid not long enough to be considered a polymer is called a(n)?
a. methacrylate
b. acrylate
c. urethane
d. oligomer
Answers
Answer:
d. oligomer it is the correct answer also if you would just search that up it pops up
What is the purpose of a signal phrase?
6.01 formation of the solar system
Answers
Answer: The purpose is to analyze the speed of planets around a central star.
Explanation: using variables
For a phase change, H = 2 kJ/mol and S = 0.017 kJ/(K-mol). What are
G and the spontaneity of the phase change at 500 K?
A. G=-6.5 kJ; nonspontaneous
B. G= 10.5 kJ; spontaneous
C. G= 10.5 kJ; nonspontaneous
D. G=-6.5 kJ; spontaneous
Answers
The reaction has a change in free energy of -6.5 kJ and is spontaneous Option D.
What is a spontaneous reaction?The term spontaneous reaction refers to a reaction that occurs with n external input of energy. We know that a spontaneous reaction is one in which the value of the change in free energy is negative. If the change in the free energy is positive then the reaction is nonspontaneous.
If the value of the change in free energy is zero then it follows that the reaction has attained equilibrium.
Now;
ΔG = ΔH - TΔS
ΔH = 2 kJ/mol
T = 500 K
ΔS = 0.017 kJ/(K-mol)
When we substitute values;
ΔG = 2 kJ/mol - (500 K * 0.017 kJ/(K-mol))
ΔG = -6.5 kJ
It the follows that the reaction has a change in free energy of -6.5 kJ and is spontaneous Option D.
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