ANSWER
EXPLANATION
Given that
The number of moles lithium bromide is 5.5 moles
Firstly, write a balanced equation for the reaction
[tex]\text{ 2Li + Br}_2\rightarrow\text{ 2LiBr}[/tex]Find the number of moles of bromine using stoichiometry ratio
Let x represents the number of bromine
[tex]undefined[/tex]6.Find the empirical formula of a compound that contains:19.16 g Sodium1.680 g Hydrogen25.81 g Phosphorus
The empitical formula shows the simplest ratio of elements in a compound (not the total number of atoms in the molecule).
So to find the empirical formula we need to calculate how many moles of each atom we have in this sample. Then we will see the ratio of each element.
We are given the mass, so to convert it to moles we use the molar mass. For this we go to the periodic table and see that the values for each element are:
Na (sodium): 22,99 g/mol
H (hydrogen): 1 g/mol
P (phosphorus): 25,81 g/mol
So we calculate the moles of each element as follows:
[tex]\begin{gathered} moles_{Na}=\frac{Mass_{Na}}{Molar\text{ }mass_{Na}}=\frac{19.16g}{22.99g/mol}=0.833\text{ mol} \\ moles_H=\frac{Mass_H}{Molar\text{ }mass_H}\text{ }=\frac{1.68g}{1g/mol}=1.68mol \\ moles_P=\frac{Mass_P}{Molar\text{m}ass_P}\text{=}\frac{25.81g}{30.97\frac{g}{mol}}=0.833mol \end{gathered}[/tex]And as we see, for every 0.833 moles of Na we have the same number of moles of P, so the ratio of these elements in the molecule is 1 to 1.
As for the hydrogen:
[tex]\frac{moles_{Na}}{moles_H}=\frac{0.833}{1.68}\approx\frac{1}{2}[/tex]So the ratio Na to H is 1 to 2.
Now we can write the empirical formula as follows=
[tex]NaH_2P[/tex]
5) A gas is held at Standard Temperature and Pressure (STP). If the gas occupies 48.4L,how many moles are present?
ANSWER
The number of moles of the gas is 2.2 moles
EXPLANATION
Given thanks
The volume of the gas is 48.4L
To find the number of moles, follow the steps below
Recall, that 1 mole is equivalent to 22.4L/mol
Let x represents the number of moles of the gas
[tex]\begin{gathered} \text{ 1 mole }\rightarrow\text{ 22.4 L/mol} \\ \text{ x mole }\rightarrow\text{ 48.4L} \\ \text{ cross multiply} \\ \text{ 1 mole }\times\text{ 48.4L }=\text{ x mole }\times\text{ 22.4l/mol} \\ \text{ Isolate x} \\ \text{ x = }\frac{\text{ 1mole}\times48.4\cancel{L}}{22.4\frac{\cancel{L}}{mol}} \\ \text{ } \\ \text{ x = }\frac{\text{ 1 }\times\text{ 48.4}}{22.4} \\ \text{ x = 2.161 moles} \end{gathered}[/tex]Hence, the number of moles of the gas is 2.2moles
Which term identifies the half-reaction that occurs at the anode of an operating electrochemical cell?(1) neutralization(2) transmutation(3) oxidation(4) reduction
ANSWER
Oxidation reaction
EXPLANATION
In an electrochemical cell, oxidation reaction occurs at the anode. This involves the loses of electrons, the electrons then flow through a wire to the cathode.
At the anode, oxidation reaction will take place
[tex]\text{ X}_{(s)\text{ }}\text{ }\rightarrow X_{(aq)}^{+\text{ }}+\text{ e}^-[/tex]My daughters CHM 130 teacher is horrible and does not teach the actual steps to the problems. Other tutors cannot figure out how she's coming up with her answers. Here is a copy of homework she did with her tutor.
5. To solve question 5, we need to know the molecular formula of Uraninite, which is UO2.
So we need to know the molar mass of U and of O. We can look for it at the periodic table.
Molar mass of Uranium: 238.02891 g/mol
Molar mass of Oxygen: 15.999 g/mol
In the compound, we have 1 uranium and 2 oxygen.
So to calculate the percent of Uranium, we use a rule of 3:
270.03 ---- 100% (It is the molar mass of the compound)
238.0289 ---- x% (It is the molar mass of uranium)
270.09 * x = 238.0289 * 100
x = 23,802.89/270.09
x = 88.13%
So the percent of uranium in uraninite is 88.13%
Now for oxygen:
We have 2 atoms of oxygen in UO2, so we need to multiply its molar mass by 2: 15.999*2 = 31.998
Now we do the same rule of 3:
270.03 ---- 100% (It is the molar mass of the compound)
31.998 ---- x% (It is the molar mass of 2 atoms of oxygen)
x = 11.72%
The percent of oxygen in uraninite is 11.72%
Answer: As a second follow up to Question 3, uraranite is 88.13% uranium and 11.72% oxygen by mass.
Use the reaction to answer the question.CH4 + 202 CO₂ + 2H₂O-H-C: 412 kJ/molO=0: 496 kJ/molC-O: 743 kJ/molO-H: 463 kJ/molWhat is the total energy of the reaction?
Answer:
The total energy reaction would be -698 kJ/mol.
Explanation:
The formula to calculate the enthalpy change of a reaction is the following:
[tex]\Delta H=\Sigma Bond\text{ energy reactants-}\Sigma Bond\text{ energy products.}[/tex]Let's calculate the bond energy for each reactant:
- CH4: As we have 4 bonds of H - C, the bond energy is 4 x 412 kJ/mol = 1648 kJ/mol.
- O2: As we have 1 bond of O = O, but we have 2 moles of O2, we just multiply the bond energy of O = O by two: 2 x 496 kJ/mol = 992 kJ/mol.
Now, let's calculate the bond energy for each product:
- CO2: As we have 2 bonds of C - O (O - C - O), the bond energy would be 2 x 743 kJ/mol = 1486 kJ/mol.
- H2O: As we have 2 bonds of O - H (O - H - O), and 2 moles of H2O, we multiply the bond energy by the number of bonds, and the number of moles: 2 x 2 x 463 kJ/mol = 1852 kJ/mol.
Finally, we just apply the given formula, like this:
[tex]\begin{gathered} \Delta H=(1648+992)\frac{kJ}{mol}-(1486+1852)\frac{kJ}{mol}, \\ \Delta H=(2640-3338)\frac{kJ}{mol}, \\ \Delta H=-698\frac{kJ}{mol}. \end{gathered}[/tex]The total energy reaction would be -698 kJ/mol.
Comapare a water molecule h2o to a dioxide molecule co2
Answer: See Below
Explanation:
H2O has two hydrogen atoms and one oxygen atom. It is a polar molecule
CO2 has one carbon molecule and two oxygen molecules. Both CO2 and H2O have two polar bonds. However the dipoles in the linear CO2 molecule cancel each other out, meaning that the CO2 molecule is non-polar.
Compare the molecules
H2NNH2 and HNNH. Which molecule has the
stronger N—N bond
Compare the Molecules H2NNH2 and HNNH. Which moecule has a stronger N-N bond? HNNH has a stronger N-N bond because it is a double bond, which is stronger than the single bond N-N bond in H2NNH2
How many grams of Fe will react with 65.2 grams of O₂?
4Fe +3022Fe2O3
Answer:
151.72 g of Fe
Explanation:
4Fe + 3O2 = 2Fe2O3
4 moles of Fe will react to 3 moles of O2
Fe has atomic mass of 55.85 g/mole
O2 has atomic mass of 16 x 2 = 32 g/mole
=> 4Fe = 4 x 55.85 = 223.4 g
=> 3O2 = 3 x 32 = 96 g
so the amount of Fe: (223.4 x 65.2)/96 = 151.72
_____energy tells us how fast the reaction willproceed.
Explanation
Kinetic energy is a modality of energy present in all moving bodies. According to the SI, its unit of measurement is the joule. Furthermore, this energy is a scalar quantity that has exclusively positive values.
Kinetic energy is proportional to the square of the body's velocity. Thus, if the speed of a body double, its kinetic energy will increase four times, if the speed of a body triple, then this increase will be nine times.
Answer
Kinect energy tells us how fast the reaction will proceed.
Arrange these gases in order of solubility, NH3, N2 CO2
The correct increasing order of solubility for the given gases is: NH₃ < N₂ < CO₂
What does solubility mean?A chemical's solubility is the maximum amount of that substance that will dissolve in a specific amount of solvent at a specific temperature. Solubility has several practical applications, including water filtering, beverage manufacturing, and vitamin storage.
Why is solubility important?The ability of a medicine to dissolve is essential to its effectiveness. A drug substance could be absorbed without it, which results in limited bioavailability. Drugs with poor solubility can potentially cause problems with metabolism or permeability, interaction with other medications, or the requirement for prolonged drug release.
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Calculate the mass of CuO which can react with 39,2 grams of orthophosphate acid.Please Help!!3CuO+ 2H3PO4 = Cu3(PO4)2 + 3H20
Answer
47.73 g CuO
Explanation
Given:
Chemical equation: 3CuO+ 2H3PO4 = Cu3(PO4)2 + 3H20
mass of orthophosphate acid (Cu3(PO4)2) = 39.2 g
Required: The mass of CuO
Solution:
[tex]\begin{gathered} 39.2g\text{ H}_3PO_4\text{ x }\frac{1\text{ mol H}_3PO_4}{97,994g\text{ H}_3PO_4}\text{ x }\frac{3\text{ moles CuO}}{2\text{ moles H}_3PO_4}\text{ x }\frac{79,545g\text{ CuO}}{1mole\text{ CuO}} \\ \\ =\text{ 47.73 g CuO} \end{gathered}[/tex]Second method:
Step 1: Find the moles of H3PO4
n = m/M where m is the mass and M is the molar mass of H3PO4
n = 39.2g/97.994g.mol^-1
n = 0.400 mol
Step 2: Use the stoichiometry to find the moles of CuO
The molar ratio between CuO and H3PO4 is 3:2
Therefore the moles of CuO = 0.400 mol x (3/2) = 0.600 mol
Step 3: Find the mass of CuO, now that we have moles
m = n x M m is the mass, n is the moles and M is the molar mass
m = 0.600 mol x 79,545 g/mol
m = 47.73 g
Potassium iodide and lead(II) nitrate solutions react together to form a precipitate of lead(II) iodide: 2KI(aq) + Pb(NO3)2(aq) → PbI2(s) + 2KNO3(aq) In each of the following cases, carry out the calculations to determine the quantities required. a If 1.0 mol of potassium iodide reacts with 1.0 mol of lead(II) nitrate, determine which reactant is in excess and by how many moles. b If 0.50 mol of potassium iodide reacts with 2.0 mol of lead(II) nitrate, determine which reactant is in excess and by how many moles. c If 1.00 g of lead(II) nitrate reacts with 1.50 g of potassium iodide, determine which reactant is in excess and the mass of lead(II) iodide that forms. d If 50.0 mL of 1.00 M lead(II) nitrate solution reacts with 75.0 mL of 0.500 M potassium iodide solution, determine which reactant is in excess the mass of lead(II) iodide that forms
As a result, 0.231liters of the 0.150M potassium iodide solution would be required to thoroughly react with the supplied lead(II) nitrate solution.
What occurs when a solution of lead nitrate combines with a solution of potassium iodide?When a solution of potassium iodide is introduced to a solution of lead nitrate in a test tube, a yellowish solid precipitates.
Lead iodide is a whitish solid. Along with lead iodide, potassium nitrate is generated. This is a reaction with two displacements.
The reaction between lead nitrate [Pb(NO3)2] and potassium iodide (Kl) results in the creation of potassium nitrate (KNO3) and a yellow precipitate of lead iodide (PbI2).
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Not a timed or graded assignment. Quick answer = rly good review :)
First jou adjust the Al, then the Br and last the K and you will see that the SO4 is adjusted.
Which of the following best describes an alkali?A. A soluble solid that forms H+ ions in a solution.B. A soluble solid that has a pH above 7.C. Any substance with a pH above 7.D. An insoluble solid that forms OH- ions in a solution.
Answer
C. Any substance with a pH above 7.
Explanation
Alkalis are water-soluble bases. bases that may be dissolved in water to produce OH⁻ ions are termed alkali. Alkali turns red litmus blue and is sour to taste. pH of an alkali substance is greater than 7.
Examples of alkali are NaOH, KOH, and Ca(OH)₂.
Hence, the answer which best describes an alkali is option C. Any substance with a pH above 7.
Identify and describe two characteristics of water molecule
Answer:
1) Water molecules are polar.
The two molecules of hydrogen are slightly positively charged, whereas the molecule of oxygen is slightly negatively charged. This is because the electrons are more attracted to the oxygen end of the molecule than the hydrogen end.
2) Water molecules frequently organize into spheres.
This is due to the molecules' mutual attraction to one another due to gravity. They also increase surface tension, which also promotes the formation of water spheres. The hydrogen bonds that exist between molecules are what produce the surface tension. This has a balance between being weak enough to be readily disturbed and robust enough to support its own weight inside the sphere.
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How will the following stresses affect this equilibrium system (iron thiocyanate system): Fe+3 {pale yellow} + SCN- FeSCN+2 {red} + heatA) Add KSCN (a source of adding SCN- ions in solution)?
ANSWER
The addition of KSCN to the system will shift the arrow to the product sides
EXPLANATION
Firstly, we need to define the term chemical equilibrium.
Chemical equilibrium can be defined as the state in which the reactants and the products are present in concentration and do not have a tendency to change with time.
To determine the shift of the chemical equilibrium in the reaction provided, state the le Chatelier's principle
Le Chatelier's principle states that when external constraints such as temperature, pressure, concentration, etc system in chemical equilibrium, the equilibrium arrow shifts so as to annul the effect of the external constraints.
From the reaction provided
[tex]\text{ Fe}^{+3}\text{ + SCN}^-\text{ }\rightleftarrows\text{ FeSCN}^{+2}\text{ + heat}[/tex]The above equation shows that the reaction is an exothermic reaction because heat is liberated to the surroundings.
When one of the reactants is supplied to the system constantly, more of its product is formed. Hence, the equilibrium arrow shifts to the right-hand side of the reaction.
Hence, the addition of KSCN to the system will shifts the arrow to the product sides
Evaluate the effectiveness of fractional distillation as a way of separating this mixture into three pure liquids.
Explanation:
Using a fractional column will help to separate liquids whit different boiling points since the mixture contain ethanol water and propanaol. Ethanol will be the first to be extracted since it has a low boiling point then it would be water and then propanaol.
You have a graduated cylinder with 20 ml. of water in it. You add 25 g of lead weights, and the volume rises to 42 ml. What is the density of lead? (No links allowed)
You have a graduated cylinder with 20 ml. of water in it. You add 25 g of lead weights, and the volume rises to 42 ml. the density of lead is 1.13 g/mL.
given data :
mass = 25 g
initial volume , V1 = 20 mL
final volume , V2 = 42 mL
volume = V2 - V1 = 42 mL - 20 mL
volume = 22 mL
density is given as :
Density = mass / volume
density = 25 g / 22 mL
density = 1.13 g/mL
Thus, You have a graduated cylinder with 20 ml. of water in it. You add 25 g of lead weights, and the volume rises to 42 ml. the density of lead is 1.13 g/mL.
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which of the follwing occurs when reactants are added to a chemical reaction in solution or the gas phase at equilibrium
When reactants are added to a chemical reaction in solution or the gas phase at equilibrium, Q decreases and equilibrium shifts to produce more reactant.
Equilibrium is the state of balance , the state when the rate of forward reaction is equal to the rate of backward reaction. When we add reactant to a chemical reaction equilibrium shifts to the rights side means from product side to produced more reactant. when we add product reaction will shifts to the left side that is in the reactant side.
Thus, When reactants are added to a chemical reaction in solution or the gas phase at equilibrium, Q decreases and equilibrium shift to produce more reactant.
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Calculate the number of molecules in 9.00 moles H2S .Express your answer numerically in molecules.
Answer
5.418 x 10²⁴ molecules
Explanation
From Avogadro's constant, 1 mole of any substance contains 6.02 x 10²³ molecules.
This implies;
1 mole H₂S = 6.02 x 10²³ molecules.
∴ 9.00 moles H₂S = x molecules
x molecules x 1 mole H₂S = 9.00 moles H₂S x 6.02 x 10²³ molecules.
[tex]\begin{gathered} x\text{ molecule }=\frac{9.00\text{ moles }H_2S\times6.02\times10^{2}^{3}\text{ }molecules}{1mole\text{ }H_2S} \\ \\ x\text{ molecules }=5.418\times10^{24}\text{ molecules} \end{gathered}[/tex]Hence, he number of molecules in 9.00 moles H₂S = 5.418 x 10²⁴ molecules
The diagrams show the arrangements of carbon atoms in diamond and in graphite. Compare a use of diamond with a use of graphite, explaining each use in terms of the bonding and structure. In your answer you should use information from the diagrams.
The diagrams show the arrangements of carbon atoms in diamond and in graphite. The diamond is sp³ hybridized and have tetrahedral shape while graphite is sp² hybridized and is hexagonal ring shaped structure.
Diamond containing carbon atoms are strongly bonded chemically with other four carbons. The carbon atoms are sp³ hybridized and make percept tetrahedral shape. Diamond used in jewelry makin g. they are used by surgeons in the cataract surgery. diamond is hard, used for cutting or drilling rock.
Graphite containing carbon atom are form the weak bond with weak forces. the carbon are sp² hybridized and make a hexagonal ring shape structure. The force in graphite in weak that makes it useful material. it is used as lubricant. it is used in pencil. used in making electrodes.
The diagrams show the arrangements of carbon atoms in diamond and in graphite. The diamond is sp³ hybridized and have tetrahedral shape while graphite is sp² hybridized and is hexagonal ring shaped structure.
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moderates weather so that highs and lows are less extreme
I need the factor of that
Moderates weather so that highs and lows are less extreme because of sea breeze motion.
Sea breeze are that as the warm air from the land is rising and the cooler air from the ocean is flowing over land and will replace the warmer air that is rising. in simple words , land gets warmer during the day than the water and the hot air rising up and cooler air move towards the land called as sea breeze. moderate weather is refers to that weather which is neither very cold nor very hot.
Thus, Moderate weather so that highs and lows are less extreme because of sea breeze motion.
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What mass of carbon monoxide is needed to react with 2.08kg of iron oxide?
Mass of carbon monoxide is needed to react with 2.08kg of iron oxide is 1.47 kg.
The balanced chemical equation is given as :
3CO + Fe₂O₃ ----> 2Fe + 3CO₂
Mass of iron oxide = 2.80kg = 2800 g
molar mass o iron oxide = 159.6 g/mol
number of moles = mass / molar mass
= 2800 / 159.69
= 17.533 mol
one mole of iron oxide react with 3 mole of carbon monoxide
17.533 react with = 3×17.533= 52.59 mol of CO
Therefore , mass of carbon monoxide = number of moles × molar mass
= 52.59 × 28
= 1472.52 g = 1.47 kg
Thus, Mass of carbon monoxide is needed to react with 2.08kg of iron oxide is 1.47 kg.
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The noble gas electron configuration of S2- isGroup of answer choices[Ar]4s2[Ne]3s2 3p4[Ne]3s2 3p6[Ar][Ne]
Answer
[Ne] 3s² 3p⁶
Explanation:
Neutral sulfur has an atomic number of 16.
Neutral sulfur has 16 electrons and 16 protons.
However, S²⁻ implies neutral sulfur has gain two more electrons.
So, S²⁻ is negatively charged (anion) and has 18 electrons.
Electronic Configuration
Neutal sulfur (S) → 1s² 2s² 2p⁶ 3s² 3p⁴ → [Ne] 3s² 3p⁴.
Charged sulfur (S²⁻) → 1s² 2s² 2p⁶ 3s² 3p⁶ → [Ne] 3s² 3p⁶.
Therefore, the electron configuration of S²⁻ is [Ne] 3s² 3p⁶.
What is the mass of 1.6x10^20 molecules of carbon monoxide?
We need to find the mass of 1.6x10^20 molecules of carbon monoxide
First, we must find the number of mol in the 1.6x10^20 molecules
For this, we need to use the avogadro's number ( 6.02*10^23 )
[tex]1.6\cdot10^{20}\cdot\frac{1\text{mol}}{6.02\cdot10^{23}}=2.66\cdot10^{-4}\text{mol}[/tex]Then, we must calculate the molar mass of carbon monoxide
M(CO) = 12 g/mol + 16 g/mol = 28 g/mol
Finally, we must multiply the number of mol by the molar mass to find the mass
[tex]2.66\cdot10^{-4}mol\cdot28\frac{g}{mol}=7.448\cdot10^{-3}g=0.007448g[/tex]ANSWER:
0.007
38 grams of lithium carbonate is dissolved in 183ml of solution. What is the molarity solution?
Answer
Molarity of the solution = 2.81 mol/L
Explanation
Given:
Mass of lithium carbonate = 38 grams
Volume of solution = 183 mL
What to find:
Molarity of the solution.
Step-by-step solution:
The molarity of the solution can be calculated using the molarity formula, which is;
[tex]Molarrity=\frac{Mole}{Volume\text{ }in\text{ }L}[/tex]First, you need to convert 38 grams of lithium carbonate to mole using the mole formula.
Molar mass of lithium carbonate = 73.891 g/mol
[tex]Mole=\frac{Mass}{Molar\text{ }mass}=\frac{38\text{ }g}{73.891\text{ }g\text{/}mol}=0.51427102\text{ }mol[/tex]Also, Volume in L = (183/1000) = 0.183 L
Putting the values of mole and volume in L into the molarity formula above, we have;
[tex]Molarity=\frac{0.51427102\text{ }mol}{0.183\text{ }L}=2.81\text{ }mol\text{/}L[/tex]Hence, the molarity of the solution is 2.81 mol/L.
What is the oxidation state on Ec in the formula below?Ec2O14
To solve this question, we need to know the oxidation state of oxygen. It is -2.
Now we can calculate.
There are 2 atoms of Ec and 14 atoms of oxygen. We multiply the number of atoms for the oxidation state and sum, everything will equal to 0, because it is a neutral compound. As we don't know the oxidation state of Ec, let's put x in its place:
2x + 14(-2) = 0
2x = 14
x = +7
Answer: The oxidation state of Ec is +7.
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4.04 Nuclear Power Generation Discussion
Formulate an argument for or against nuclear power. It should be well thought-out and a minimum of seven complete sentences.
Formulate an argument for or against nuclear power it should be well thought-out and a minimum of seven complete sentences and they are water intensive and environmental impact
Nuclear power is the clean and efficient way of boiling water to make stream and which turn turbined to produce electricity and the nuclear power plant use enriched uranium fuel to produce electricity through process called fission
And the argument against nuclear power is
Environmental impactWater intensiveRisk of nuclear accidentsRadioactive wasteNon-renewable energy sourceKnow more about arguments
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a chemical company makes a silver by reacting silver nitrate would see the company needs to make 800 g of pure silver for a client they have 300 g of zinc and 600 g of silver nitrate will they be able to make enough silver to fill the order
Answer
Explanation
Given that:
The mass of pure silver needed = 800 g
Mass of zinc = 300 g
Mass of silver nitrate = 600 g
What to find:
Will the mass of zinc and silver nitrate be able to make 800 g of pure silver.
Step-by-step solution:
Step 1: Write the balanced equation for the reaction.
Zn + 2AgNO₃ → 2Ag + Zn(NO₃)₂
Step 2: Determine the moles of the reactants.
Using the mole formula, the moles of the reactants will be:
[tex]\begin{gathered} Moles\text{ }of\text{ }Zn=\frac{Mass}{Molar\text{ }mass}=\frac{300g}{65.38g\text{/}mol}=4.5886\text{ }mol \\ \\ Moles\text{ }of\text{ }AgNO_3=\frac{600g}{169.87g\text{/}mol}=3.5321\text{ }mol \end{gathered}[/tex]Step 3: Determine the moles of pure silver produced.
Using the mole ratio of Zn to AgNO₃ in the equation and the moles in step 2, we
In an experiment, 3.25 g of C3H8 react with 3.50 g of O2.1) Write the formula for the reactant that is the limiting reactant.
So,
The reaction that takes place here is the next one:
The first thing we're going to do is to pass the mass of each compound to moles. (We do this just dividing by the molecular weight of the compound):
Now, the last step is just to divide each amount by the coefficient of the reaction of each compound. The smaller result will be the limiting reactant.
Therefore, the limiting reactant is O2.