Answer:
1 used in paint , toothpaste
2 used in fireworks and magnets
3 used to manufacture alloys
Nitric acid can be formed in two steps from the atmospheric gases nitrogen and oxygen, plus hydrogen prepared by reforming natural gas. In the first step, nitrogen and hydrogen react to form ammonia: N2 (g) + 3H2 (g) â 2NH3 (g) =ÎHâ92.kJ In the second step, ammonia and oxygen react to form nitric acid and water:
NH3 (g) + 2O2 (g) â HNO3 (g) + H2O (g) =ÎHâ330.kJ
Required:
Calculate the net change in enthalpy for the formation of one mole of nitric acid from nitrogen, hydrogen and oxygen from these reactions.
Answer:
-376 kJ
Explanation:
The first step equation:
[tex]\mathsf{N_{2(g)} + 3H_2{(g)} \to 2NH_3{(g)} \ \ \ \Delta H = -92\ kJ}[/tex] ---- (1)
The second step equation:
[tex]\mathsf{NH_{3(g)} + 2O_2{(g)} \to HNO_3{(g)} +H_2O_{(g)} \ \ \ \Delta H = -330\ kJ}[/tex] ---- (2)
To determine the enthalpy of formation for 1 mole of HNO₃ (nitric acid), we have the following.
From the above equations; let multiply equation (1) by 1 and equation (2) by 2.
[tex]\mathsf{N_{2(g)} + 3H_2{(g)} \to 2NH_3{(g)} \ \ \ \Delta H = -92\ kJ}[/tex] ---- (3)
[tex]\mathsf{2NH_{3(g)} + 4O_2{(g)} \to 2HNO_3{(g)} +2H_2O_{(g)} \ \ \ \Delta H = 2(-330)\ kJ}[/tex] ----- (4)
adding the above two equations, we have:
[tex]\mathsf{N_{2(g)} + 3H_2{(g)}+ 2NH_{3(g)} + 4O_{2(g)} \to 2HNO_{3(g)} + 2NH_3{(g)} +2H_2O_{(g)} \ \ \ \Delta H = (-660 \ kJ -92\ kJ)}[/tex][tex]\mathsf{N_{2(g)} + 3H_2{(g)} + 4O_{2(g)} \to 2HNO_{3(g)} +2H_2O_{(g)} \ \ \ \Delta H = (-752 \ kJ)}[/tex]
Now, from the recent equation, we have:
2 moles of nitric acid = -752 kJ
∴
1 mole of nitric acid will be: = (1 mole × (-752 kJ)) ÷ 2 moles
1 mole of nitric acid will be: = -376 kJ
If a buffer is composed of 23.34 mL of 0.147 M acetic acid and 33.66 mL of 0.185 M sodium acetate, how many mL of 0.100 M NaOH can be added before the buffer capacity is reached
Answer:
25.5mL of 0.100M NaOH are needed to reach buffer capacity.
Explanation:
The buffer capacity is reached when the ratio between moles of conjugate base (Sodium acetate) and moles of weak acid (Acetic acid) is 10:
Moles sodium acetate / Moles Acetic acid = 10
The reaction of acetic acid, HA, with NaOH, to produce sodium acetate, NaA is:
HA + NaOH → H2O + NaA
That means the moles of NaOH added = Moles of HA that are being subtracted and moles of NaA that are been produced.
The initial moles of each species is:
Acetic acid:
23.34mL = 0.02334L * (0.147mol / L) = 0.00343 moles Acetic Acid
Sodium Acetate:
33.66mL = 0.03366L * (0.185mol / L) = 0.00623 moles Sodium Acetate
We can write the moles of each species when NaOH is added as:
Moles sodium acetate / Moles Acetic acid = 10
0.00623 moles + X / 0.00343 moles - X = 10
Where X are moles of NaOH added
Solving for X:
0.00623 moles + X = 0.0343 moles - 10X
11X = 0.0281
X = 0.00255 moles of NaOH are needed
In Liters:
0.0255mol NaOH * (1L / 0.100mol) = 0.0255L of 0.100M NaOH are needed =
25.5mL of 0.100M NaOH are needed to reach buffer capacity
Assume you have 4 solids (A, B, C and D) of similar mass. Which of these requires the greatest energy input to melt?
polar covalent
covalent network
ionic compound
nonpolar covalent
The solid that require the greatest energy input to melt by mass is the option;
Covalent network
Reason for the above answer is as follows;
The elementary particles of a solid are held together by bonds that require
an input of energy to unlock, and once broken, the particles are then able
to change location within their containing vessels with less restrictions
Types of bonds
Polar covalent molecular solids have the following characteristics;a) Soluble in water b) Low melting point, b) Conduct electricity
Solids that are made up of a covalent network have the following characteristicsa) High melting point temperature b) Non conductive of electricity c) Not soluble in water
Solids of ionic compounds have the following characteristics;a) High melting point temperature b) The liquid state and solution
conducts electricity c) Soluble in water
Solids that have nonpolar covalent bonds have;a) Low melting point b) Normally in the gaseous or liquid state b) Not water soluble
Therefore, the covalent network, and the solids ionic compounds require the most energy to melt, however, the strength of the ionic bond in an ionic compound is a factor the charges present and the sizes of the atom, while
the covalent network solid, are combined to form essentially as a single
molecule and therefore require the greatest heat energy input break the bonds of the molecule down in order to melt
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why is it difficult to undergo nucleophilic substitution in haloarene?
Answer:
In Haloarenes the C atom to which the X group is attached is SP2 hybridized thus it is become difficult to replace it by the Nucleophile. Since arenes and Vinyl halides are electron rich molecules due to presenceof n bonds, they repel Nucleophile attacking them.
Question:-
Why it is difficult for haloarenes to undergo nucleoplhilic subsituⁿ reaction?
Answer:-
Haloarenes are less reactive towards the nucleoplhilic substitution rxⁿ . This is due to following reasons :-
[tex]\red{\bigstar}\underline{\textsf{ Reason 1 :- Partial double bond character .}}[/tex]
Halogen atom has one lone pair, and due to presence of π - σ - lp , resonance is established in the compound ( see attachment) . Due to resonance there is a partial double bond character in the carbon halogen bond , so it is difficult to break a double bond than a single bond.
[tex]\rule{200}2[/tex]
[tex]\red{\bigstar}\underline{\textsf{ Reason 2 :- $\pi$ cloud .}}[/tex]
When a nucleoplhile comes to attack , it is repelled by the π-cloud of the benzene ring.
[tex]\rule{200}2[/tex]
[tex]\red{\bigstar}\underline{\textsf{ Reason 3 :- Phenyl cation .}}[/tex]
If somehow the halogen atoms leaves the benzene ring ,being more electronegative than carbon , it takes away the electron , thus a positive charge is left on benzene ring and the phenyl cation so formed is very unstable .
[tex]\rule{200}2[/tex]
write the chemistry of Epsom salt
6) Hydrogen gas can be generated from the reaction between aluminum metal and hydrochloric acid:
2 Al(s) + 6 HCl(aq) + 2 AICI3, (aq) + 3 H2(g)
a. Suppose that 3.00 grams of Al are mixed with excess acid. If the hydrogen gas produced is directly collected
into a 850 mL glass flask at 24.0 °C, what is the pressure inside the flask (in atm)?
b. This hydrogen gas is then completely transferred from the flask to a balloon. To what volume (in L) will the
balloon inflate under STP conditions?
c. Suppose the balloon is released and rises up to an altitude where the temperature is 11.2 °C and the pressure is
438 mm Hg. What is the new volume of the balloon (in L)?
Stoichiometry refers to the relationship between the moles of reactants and products.
This question must be solved using both stoichiometry and the gas laws
The reaction equation is;
2 Al(s) + 6 HCl(aq) --------> 2 AICI3, (aq) + 3 H2(g)
Using stoichiometryNumber of moles of Al = 3g/27g/mol = 0.11 moles
According to the reaction equation;
2 moles of Al yields 3 moles of H2
0.11 moles of Al yields 0.11 * 3/2 = 0.165 moles
Using the gas lawsFrom the ideal gas equation;
PV=nRT
P = ?
n= 0.165 moles
V = 0.85 L
T = 297 K
R = 0.082 atmLK-1mol-1
P= nRT/V
P = 0.165 * 0.082 * 297/0.85
P= 4.73 atm
Under STP conditions;P1 = 4.73 atm
T1 = 297 K
V1 = 0.85 L
P2 = 1 atm
T2 =273 K
V2 =?
From the general gas equation;P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 4.73 * 0.85 * 273/1 * 297
V2 = 3.69 L
P1 = 760 mmHg
T1 = 273 K
V1 = 3.69
P2 = 438 mm Hg
T2 = 284.2 K
V2 =?
P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 760 * 3.69 * 284.2/438 *273
V2 = 797010.48/119574
V2= 6.67 L
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An ordinary gasoline can measuring 30.0 cm by 20.0 cm by 15.0 cm is evacuated with a vacuum pump.
1a. Assuming that virtually all of the air can be removed from inside the can, and that atmospheric pressure is 14.7 psi, what is the total force (in pounds) on the surface of the can?
1b. Do you think that the can could withstand the force?
Answer:
Explanation:
From the given information:
The surface area of the can = (30 × 20 × 2) +(20× 15 × 2) +(30 × 15 × 2)
= 1200 + 600 + 900
= 2700 cm²
Since 1 inch² = 0.155 inch²
The surface area in inches² = 2700 × 0.155 inch²
= 418.5 inches²
The total force can be determined by using the expression:
Force = Pressure ×Area
Force = 14.7 psi × 418.5 inches²
Force = 6151.95 lbs
Yes, the gasoline can will be able to withstand the force.
3 molecules NaOH determine the amount of grams
Answer:
In three mocelus 0.0001 gram.
A hot pot of water is set on the counter to cool. After a few minutes it has lost 495 J of heat energy. How much heat energy has the surrounding air gained?
_____unit_____
Answer:
495 J
Explanation:
When the hot pot was set on the counter to cool, heat energy was lost from the pot. Note that according to the first law of thermodynamics, heat is neither created nor destroyed.
This implies that, the heat energy lost from the pot must be gained by the surrounding air. Therefore, if 495 J of energy is lost from the pot, then 495 J of energy is gained by the surrounding air.
Lewis Structures are used to describe the covalent bonding in molecules and ions. Draw a Lewis structure for NO3- and answer the following questions based on your drawing.
1. For the central nitrogen atom:
The number of lone pairs = ________
The number of single bonds=_______
The number of double bonds= ______
2. The central nitrogen atom :
Answer:
The lewis structure for NO₃⁻ is shown in the attachment below
For the central nitrogen atom:
The number of lone pairs = 0
The number of single bonds = 2
The number of double bonds= 1
Explanation:
The lewis structure for NO₃⁻ is shown in the attachment below.
From the Lewis structure
For the central nitrogen atom:
The number of lone pairs = 0
The number of single bonds = 2
The number of double bonds= 1
If we increase the temperature of the reaction that occurs in plants to create sugar. What direction does the equilibrium shift....
- Products
- No change
- Reactants
- Plants are not capable of this
The reaction used to produce sugar in plants is Photosynthesis,
6CO₂ + 6H₂O + heat ⇆ C₆H₁₂O₆ + 6O₂↑
we can see that this reaction is endothermic, it absorbs heat to occur
If we were to add more heat or increase the temperature, the left side of the equilibrium will be able to react much more, which would produce more glucose (aka sugar)
Hence increasing the temperature will shift the equilibrium to the right or towards the Products
Answer:
Explanation:
The reaction that occurs in plants to create sugar can be represented by the following equation:
6 CO2 + 6 H2O ↔ C6H12O6 + 6 O2
It is called photosynthesis because the reaction requires light energy for the plant. The reaction is controlled by enzyme within the plant. An increase in temperature will increase the collisions between enzyme and reactants; shifting the equilibrium towards the products, sugar and oxygen.
If Sterling silver is 90.0% silver and 10.0% copper, what is the maximum amount of Sterling silver that can be made if you have 48.3 grams of silver metal and an unlimited amount of copper
Answer:
[tex]x=54g[/tex]
Explanation:
From the question we are told that:
Content of Sterling silver:
Let x be sterling silver
Silver [tex]S=0.9x[/tex]
Copper [tex]C=0.1x[/tex]
Total silver available [tex]T=48.3[/tex]
Generally the equation for Total amount to be made is mathematically given by
[tex]T=\frac{x*90}{100}[/tex]
[tex]x=\frac{48.3*100}{90}[/tex]
[tex]x=54g[/tex]
In order to complete the reaction of hexyl magnesium bromide with acetone, what next step needs to be done.
a. Fractional Distillation.
b. Vacuum filtration.
c. Aqueous workup.
d. Crystallization.
Answer:
Aqueous workup.
Explanation:
The reaction of hexyl magnesium bromide with acetone yields a tertiary alcohol. There is an organic phase and an aqueous phase.
Aqueous workup is the process of recovering the pure tertiary alcohol from the organic phase of the system.
Hence, in order to complete the reaction of hexyl magnesium bromide with acetone, aqueous workup is required.
What is the job of cellular respiration?
Answer:
to break down sugar in the presence of oxygen to release energy in the form of ATP
Explanation: i just finished this chapter of the class
The reversible reaction 2H2 CO <------> CH3OH heat is carried out by mixing carbon monoxide and hydrogen gases is a closed vessel under high pressure with a suitable catalyst . After equilibrium is established at high temperature and pressure, all three substances are present. If the pressure on the system is lower, with the temperature kept constant, what will be the result
Answer:
The amount of CH3OH present in the mixture would decrease
Explanation:
According to Le Cha-telier's principle, when a reaction is in equilibrium and one of the constraints that influence the rate of reactions is applied, the equilibrium would shift so as to neutralize the effects of the constraint.
In this case, looking at the equation of the reaction:
2H2 + CO <------> CH3OH + heat
the total number of moles on the reactant's (left hand) side is 3 (2+1) while on the product's (right hand) side, it is 1. If the pressure on the system is increased, more CH3OH (and less of H2 and CO) will be produced because its side has the lower number of moles out of the two sides.
If the pressure on the system is otherwise lowered, more of H2 and CO would be produced while the amount of CH3OH present would gradually decrease.
An analytical chemist is titrating of a solution of benzoic acid with a solution of . The of benzoic acid is . Calculate the pH of the acid solution after the chemist has added of the solution to it. Note for advanced students: you may assume the final volume equals the initial volume of the solution plus the volume of solution added.
The question is incomplete. The complete question is :
An analytical chemist is titrating 148.9 mL of a 1.100 M solution of benzoic acid [tex]$HC_6H_5CO_2$[/tex] with a 0.3600 M solution of KOH. The [tex]pK_a[/tex] of benzoic acid is 4.20. Calculate the pH of the acid solution after the chemist has added 232.0 mL of the KOH solution to it. Note for advanced students: you may assume the final volume equals the initial volume of the solution plus the volume of KOH solution added.
Solution :
Number of moles of [tex]$C_6H_5OCOOH$[/tex] [tex]$=148.9 \ mL \times \frac{L}{1000\ mL} \times \frac{1.100 \ mol}{L}$[/tex]
= 0.16379 mol
Number of moles of NaOH added [tex]$=232.0 \ mL \times \frac{L}{1000\ mL} \times \frac{0.3600 \ mol}{L}$[/tex]
= 0.08352 mol
ICE table :
[tex]C_6H_5OCOOH \ \ \ + \ \ \ OH^- \ \ \ \rightarrow \ \ C_6H_5OCOO^- \ \ \ \ + \ \ H_2O[/tex]
I (mol) 0.16379 0.08352 0
C (mol) -0.08352 -0.08352 +0.08352
E (mol) 0.08027 0 0.08352
Total volume = (148.9 + 232) mL
= 380.9 mL
= 0.3809 L
Concentration of [tex]$C_6H_5OCOOH, [C_6H_5OCOOH]$[/tex] [tex]$=\frac{0.08027 \ mol}{0.3809 \ L}$[/tex]
= 0.211 M
Concentration of [tex]$C_6H_5OCOO^- , [C_6H_5OCOO^-] =\frac{0.08352 \ mol}{0.3809 \ L}[/tex]
= 0.219 M
[tex]pK_a[/tex] of [tex]C_6H_5OCOOH = 4.20[/tex]
According to Henderson equation,
[tex]$pH = pK_a + \log \frac{[C_6H_5OCOO^-]}{[C_6H_5OCOOH]}[/tex]
[tex]$=4.20 + \log \frac{0.219}{0.211}$[/tex]
= 4.22
Therefore, the pH of the acid solution is 4.22
Which combination of reagents used in the indicated order with benzene will give m-nitropropylbenzene? a. 1) CH3CH2CH2Cl/AlCl3, 2) HNO3/H2SO4 b. 1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3 c. 1) CH3CH2CH2Cl/AlCl3, 2) HNO3/H2SO4, 3) Zn/HCl d. 1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3, 3) Zn/HCl
Answer:
1) HNO3/H2SO4, 2) CH3CH2CH2Cl/AlCl3
Explanation:
Benzene is a stable aromatic compound hence it undergoes substitution rather than addition reaction.
When benzene undergoes substitution reaction, the substituent introduced into the ring determines the position of the incoming electrophile.
If I want to synthesize m-nitropropylbenzene, I will first carry out the nitration of benzene using HNO3/H2SO4 since the -nitro group is a meta director. This is now followed by Friedel Craft's alkykation using CH3CH2CH2Cl/AlCl3.
Activation energy is:
A. The energy needed to begin breaking the bonds of reactants.
B. None of these.
C. The maximum amount of energy reactants can hold.
D. The energy needed to begin breaking the bonds of products.
Activation energy is the energy needed to begin breaking the bonds of reactants. Hence, option A is correct.
What is activation energy?Activation energy is defined as the minimum amount of energy necessary to initiate a chemical reaction.
Hence, activation energy is the energy needed to begin breaking the bonds of reactants.
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Ammonium phosphate NH43PO4 is an important ingredient in many fertilizers. It can be made by reacting phosphoric acid H3PO4 with ammonia NH3. What mass of ammonium phosphate is produced by the reaction of 5.5g of phosphoric acid
Answer:
8.3 g
Explanation:
Step 1: Write the balanced equation
H₃PO₄ + 3 NH₃ ⇒ (NH₄)₃PO₄
Step 2: Calculate the moles corresponding to 5.5 g of H₃PO₄
The molar mass of H₃PO₄ is 97.99 g/mol.
5.5 g × 1 mol/97.99 g = 0.056 mol
Step 3: Calculate the moles of (NH₄)₃PO₄ produced
The molar ratio of H₃PO₄ to (NH₄)₃PO₄is 1:1. The moles of (NH₄)₃PO₄ produced are 1/1 × 0.056 mol = 0.056 mol.
Step 4: Calculate the mass corresponding to 0.056 moles of (NH₄)₃PO₄
The molar mass of (NH₄)₃PO₄ is 149.09 g/mol.
0.056 mol × 149.09 g/mol = 8.3 g
How many oxygen atoms are there in 0.25 mole of CO2?
Answer:
It is known that 1 mol of a molecule contains 6.023×1023 6.023 × 10 23 number of molecules. So, 0.25 moles of CO2 C O 2.
The correct option for the given question about Mole Concept is Na / 2 atom of oxygen.
What is mole?In chemistry, a mole is a unit. A mole of a substance is the mass of the substance containing precisely 12 gram of the same number of atoms as 12C.The mole is the SI unit used to measure a substance's quantity. It has the symbol mol.
How to solve this question?
In 1 mole number of molecules of CO₂ = Na (Avagadro Number)
In 0.25 mole number of molecules of CO₂ = 0.25 × Na molecules
In 1 molecule number of oxygen atom = 2 atom
In 0.25 × Na molecules number of oxygen atom = 2 × 0.25 × Na atom
In 0.25 × Na molecules number of oxygen atom = 0.5 × Na atom
So in 0.25 mole of CO₂ number of oxygen atom = Na / 2 atom
Thus we can conclude that in 0.25 mole of CO₂ number of oxygen atom will be Na / 2, where Na is Avagadro Number.
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Consider the reaction below. How much heat is absorbed if 5.00 moles of nitrogen react
with excess oxygen?
2 N2 (8) + O2(g) → 2 N20 (8) AHrxn- +163.2 kJ
Explanation:
The given chemical reaction is:
[tex]2 N_2 (g) + O_2(g) -> 2 N_20 (g) delta Hrxn= +163.2 kJ[/tex]
When two moles of nitrogen reacts with oxygen, it requires 163.2kJ of energy.
When 5.00 mol of nitrogen requires how much energy?
[tex]5.00 mol x \frac{163.2 kJ }{2 mol} \\=408 kJ[/tex]
Hence, the answer is 408 kJ of heat energy is required.
plzzz guys help it urgent
Answer:
requiring immediate action or attention.
word similar to urgent: Acute
Of these gases, which has the fastest-moving molecules (on average) at a given temperature?
-N2
-They all have the same average speed.
-Cl2
-HCl
Which gas molecules have the highest average kinetic energy at a given temperature?
-They all have the same average kinetic energy.
-Cl2
-HCl
-N2
Answer:
a) N2
b) They all have the same average kinetic energy.
Explanation:
At a given temperature, the speed of a gas molecule depends on its relative molecular mass. The heavier the gas, the lesser its average velocity at a given temperature. On that basis, N2 molecules are the fastest moving gas molecules.
At a particular temperature, all gases have the same average kinetic energy.
Choose the compound below that contains at least one polar covalent bond, but is nonpolar.
a. SiF4
b. SeF4
c. HCl
d. ICl3
e. Both SiF4 and ICl3 are nonpolar and contain a polar covalent bond.
Answer:
HCl contain a polar covalent bond because H is more electropositive than Cl and Cl is more electronegative than H, resulting in a dipole moment
What is the molarity of a solution that contains 0.75 mol Naci in 3.0 L of solution? Select one: O a. 4.0 M O b. 2.3 M O d. 3.8 M O d. 0.25 M Clear my choice
Answer:
[tex]\boxed {\boxed {\sf D. \ 0.25 \ M}}[/tex]
Explanation:
Molarity is a measure of concentration in moles per liter.
[tex]molarity= \frac{moles \ of \ solute}{ liters \ of \ solution}[/tex]
The solution contains 0.75 moles of sodium chloride and has a volume of 3.0 liters.
moles of solute = 0.75 mol NaCl liters of solution = 3.0 LSubstitute these values into the formula.
[tex]molarity= \frac{ 0.75 \ mol \ NaCl}{3.0 \ L}[/tex]
[tex]molarity= 0.25 \ mol \ NaCl/L[/tex]
Molarity has the molar (M) as its unit. 1 molar is equal to 1 mole per liter.
[tex]molarity= 0.25 \ M \[/tex]
The molarity of the solution is 0.25 Molar and Choice D is correct.
When hydrogen gas reacts with oxygen gas, water vapour is formed according to the
reaction 2H2 + O2 2H2O. If 3.00 mol of hydrogen gas react with 3.00 mol
of oxygen gas, which reactant will be the reactant in excess?
Explanation:
here's the answer to the question
Which of the following is a reduction half-reaction?
Solution : An oxidation reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between tow species an oxidaion reductin reaction is any chemical reaction in which the oxidation number of a molecule atom or ion changes by gaining or losing an electron
When comparing Be2 and H2:
I. Be2 is more stable because it contains both bonding and antibonding valence electrons.
II. H2 has a higher bond order than Be2.
III. H2 is more stable because it only contains 1s electrons.
IV. H2 is more stable because it is diamagnetic, whereas Be2 is paramagnetic
a. II,III,IV
b.II,III
c.III only
d.I,II
e.III,IV.
Answer:
The answer is "Option b".
Explanation:
H2 does have bond energy of 1, while Be2 has a covalent bond of zero. Be2 has eight electrons, each of which dwells in a distinct orbital. As just a result, four of them are linked molecular orbitals and two are antibonding molecular orbitals, respectively. As just a result, this molecule is unstable. This chemical orbital, with a bond order of 1, has just two electrons. As a result, it is a very solid substance. H2's bond length is higher than Be2's. Since it only has one electron, H2 is more stable than that of other compounds.
The Lewis dot model of a molecule is shown.
Based on the model, which of the following is true?
Each carbon has three lone pairs of electrons on it.
The octet of carbon atom remains incomplete in the molecule.
The two carbon atoms share a total of six electrons with each other.
The difference between the electronegativity of carbon and hydrogen is greater than 1.7.
Answer:
The two carbon atoms share a total of six electrons with each other.
Explanation:
Looking at the structure of the molecule H-C≡C-H as shown in the question, we will notice that there exists a triple bond between the two carbon atoms.
Each bond between the two carbon atoms represents two electrons shared. Since there are three bonds between the two carbon atoms, then a total of six electrons were shared between the two carbon atoms hence the answer chosen above.
Hydrogen fluoride will react with glass (silicon dioxide. S_iO_2) according to the equation below What mass of HF is required to react completely with 16 0 g of glass? (Molar masses; Si 28 09 g/mol F 19 00 g/mol H. 1.01 g/mol O, 16.00 g/mol]
4HF(g) + SiO_2(s) --> SiF_4(g) + 2H_2O(g)
A. 5.33 g
B. 21.3 g
C. 64.0 g
D. 80.0 g
E. 320 g
Answer:
21.3 g. Option B
Explanation:
The reaction is:
4HF(g) + SiO₂(s) → SiF₄(g) + 2H₂O(g)
We analysed it and it is correctly balanced.
4 moles of hydrogen fluoride react to 1 mol of silicon dioxide in order to produce 1 mol of silicon fluoride and 2 moles of water vapor.
We determine molar mass of each reactant:
HF → 1.01 g/mol + 19 g/mol = 20.01 g/mol
SiO₂ → 16 g/mol . 2 + 28.09 g/mol = 60.09 g/mol
We convert mass to moles: 16 g . 1 mol /60.09g = 0.266 moles of glass
Ratio is 1:4. 1 mol of glass react to 4 moles of HF
Our 0.266 moles may react to (0.266 . 4) / 1 = 1.07 moles of gas
We convert moles to mass: 1.07 mol . 20.01 g/mol = 21.3 g
