Answer:
Mass = 13.42 g
Explanation:
Given data:
Molality of potassium chloride solution = 0.721 m
Mass of water = 255 g (255 g /1000 = 0.255 Kg)
Potassium chloride added = ?
Solution:
Molality:
Molality = number of moles of solute/ Kg of solvent
0.721 m = moles / 0.255 Kg
m = mol/Kg
Moles = 0.721mol/Kg×0.255 Kg
Moles = 0.18 mol
Mass of potassium chloride:
Number of moles = mass/molar mass
0.18 mol = Mass /74.55 g/mol
Mass = 0.18 mol × 74.55 g/mol
Mass = 13.42 g
This equation is balanced: N2+3H2 - 2NH3 O
A. True •
B. False
Answer:
True
Explanation:
N2 + 3h2 - 2NH3 is indeed a balanced equation therefore it is a "true statement" or option A. You can tell this equation is balanced because it has the same number of Nitrogen, and Hydrogen atoms on the same side keeping the equation balanced.
Hope this helps.
Identify which of the following equations are balanced.A. 6Li(s)+N2(g)→2Li3N(s)6Li(s)+N2(g)→2Li3N(s).B. 2KMnO4(s)→K2MnO4(s)+MnO2(s)+O2(g). C. 2KClO3(s)→2KCl(s)+O2(g)2KClO3(s)→2KCl(s)+O2(g). D. Mg(s)+N2(g)→Mg3N2(s)Mg(s)+N2(g)→Mg3N2(s).
Answer:
love u baby doll thanks for the help
H3C-CH2-C-CH2-CH2-CH3
CH-CH3
what is the formula of butane
Answer:
Butane : CH3 - CH2 - CH2 - CH3
Explanation:
The word Butane has "But" as preffix which stands for 4 carbon atoms & "ane" as suffix which tells that the compound is of alkane homologous series .
What is the “nature” of the water cycle?
Answer:
Continuously recurring, or cycling maybe?
Answer:
a process that recirculates earth's water through the stages of evaporation condensation and collection. The water from lakes, oceans, rivers and other water bodies began to evaporate vapor from the water bodies, condensates and the clouds later causing precipitation
I NEED THIS RIGHT NOW OR I GET AN F!!!!! HELP!!!!!
What types of geological events can the following interactions produce?
Divergent boundaries:
Convergent boundaries:
Transform boundaries:
Answer: Divergent boundaries -- where new crust is generated as the plates pull away from each other. Convergent boundaries -- where crust is destroyed as one plate dives under another. Transform boundaries -- where crust is neither produced nor destroyed as the plates slide horizontally past each other.
Explanation:
earthquakes volcanos n stuff like that
The mass of water in a single popcorn kernel was found to be 0.905 grams after it popped at a temperature of 175 °C. Using the information given in the Introduction, calculate the amount of heat in kilojoules required to pop this single kernel if the room temperature was recorded to be 21.0 °C.
Answer:
0.583 kilojoules
Explanation:
The amount of heat required to pop a single kernel can be calculated using the formula as follows:
Q = m × c × ∆T
Where;
Q = amount of heat (J)
m = mass of water (g)
c = specific heat capacity of water (4.184 J/g°C)
∆T = change in temperature
From the given information, m = 0.905 g, initial temperature (room temperature) = 21°C , final temperature = 175°C, Q = ?
Q = m × c × ∆T
Q = 0.905 × 4.184 × (175°C - 21°C)
Q = 3.786 × 154
Q = 583.044 Joules
In kilojoules i.e. we divide by 1000, the amount of heat is:
= 583.04/1000
= 0.583 kilojoules
For the following reaction, 5.78 grams of chlorine gas are mixed with excess iron. The reaction yields 6.79 grams of iron(III) chloride.
2Fe (s) + 3Cl2 (g) → 2FeCl3 (s)
a. What is the theoretical yield of iron(III) chloride?
b. What is the percent yield for this reaction?
Answer:
a. Theoretical yield = 8.81 g
b. 77 %
Explanation:
We begin from the reaction:
2Fe (s) + 3Cl₂ (g) → 2FeCl₃ (s)
and the excess is the iron, so the limiting reagent is the chlorine.
We convert mass to moles → 5.78 g / 70.90 g/mol = 0.0815 mol
Ratio is 3:2 so we think this:
From 3 moles of chlorine, I can produce 2 moles of Iron (III) chloride
Then 0.0815 moles would produce (0.0815 . 2) /3 = 0.0543 moles
This is the theoretical yield. We convert the moles to mass:
0.0543 mol . 162.2 g /mol = 8.81 g
If the reaction yields 6.79 g of FeCl₃ and the theoretical yield is 8.81 g ,we can obtain the percent yield: (6.79 / 8.81) . 100 = 77 %
A photovoltaic cell converts light into electrical energy. Suppose a certain photovoltaic cell is only 63.5% efficient, in other words, that 63.5% of the light energy is ultimately recovered. If the energy output of this cell is used to heat water, how many 520 nm photons must be absorbed by the photovoltaic cell in order to heat 10.0 g of water from 20.0°C to 30.0°?
Answer:: A photovoltaic cell converts light into electrical energy. Suppose a certain photovoltaic cell is only 63.5% efficient, in other words, that 63.5% of the light energy is ultimately recovered. If the energy output of this cell is used to heat water, how many 520 nm photons must be absorbed by the photovoltaic cell in order .
Explanation:
Question 10
2 pts
(2 points) What is the molarity of a solution when 25.0 mL of 0.500 M NaCl is diluted to 150.0 mL?
Show your work. No work = no credit.
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Answer:
M₂ = 0.08 M
Explanation:
Given data:
Initial volume = 25.0 mL
Initial molarity = 0.500 M
Final volume = 150.0 mL
Final molarity = ?
Solution:
Formula:
M₁V₁ = M₂V₂
0.500 M × 25.0 mL = M₂ × 150.0 mL
M₂ = 0.500 M × 25.0 mL / 150.0 mL
M₂ = 12.5 M.mL /150.0 mL
M₂ = 0.08 M
Select the molecule where free rotation around one or more bonds is not possible. Group of answer choices N2H4 C2Cl4 NH3 C2H6 CCl4
Answer:
C₂Cl₄
Explanation:
To know if free rotation around a bond in a compound is possible, we need to see the structure of the compound (picture in attachment).
In single bonds, which are formed by σ bonds, the atoms are not fixed in a single position, and free rotation is permitted.
Double and triple bonds are formed by a σ bond and one or two π bonds, respectively. These bonds do not allow rotation, since it is not possible to twist the ends without breaking the π bond.
The chloroethylene (C₂Cl₄) has two carbons with an sp2-sp2 hybridization, they are bonded together by a double bond. Free rotation on this bond is not possible, because six atoms, including the carbon atoms, doubly bonded and the four chlorine atoms bonded to them, must be on the same plane.
Can you help with these two questions pleaseeee
Answer: H2Te
Explanation:
H2Te has the highest molecular weight and thus it has the highest boiling point from H2S and H2Se.
Calcium metal reacts with fluorine gas to form solid calcium fluoride. When the reaction is balanced, what coefficient is in front of fluorine gas?
A. 1
B. 2
C. 7
D. 3
Answer:
B= 2
Explanation:
Chemical equation:
Ca + F → CaF₂
Balance chemical equation:
Ca + 2F → CaF₂
Step 1:
Ca + F → CaF₂
Left hand side right hand side
Ca = 1 Ca = 1
F = 1 F = 2
Step 2:
Ca + 2F → CaF₂
Left hand side right hand side
Ca = 1 Ca = 1
F = 2 F = 2
Choose all the answers that apply.
Which of the following statements are true?
OThe space between neurons is called a synapse.
OThe nucleus of a neuron is located in the cell body.
O Practice can increase the speed of neuron signal transfer.
0Axons carry messages toward the cell body.
o Electrical impulses in neurons go two ways.
Answer:
I think this the right answer maybe, the space between neurons is called a synapse. The nucleus of a neuron is located in the cell body. Axons carry messages toward the cell body. These are the true ones I think.
Explanation:
Answer:
1,2, and 4
Explanation:
A mass scale reads 10 kilograms on earth, what would it read on the moon?
Select the pair of compounds that you would expect to form a homogeneous solution based on intermolecular forces. Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices CBr4 and NH3 CCl4 and H2O NH3 and H2O Br2 and HCl
Answer:
NH3 and H2O
Explanation:
In chemistry, the overarching principle of like dissolve like decides the solubility of one substance in another. This principle is ultimately hinged on the idea of intermolecular forces existing between substances. Polar substances dissolve polar substances while nonpolar substances dissolve nonpolar substances in accordance with this principle.
Both NH3 and H2O are polar substances that contain the hydrogen bond. Intermolecular hydrogen bonding interaction accounts for the solubility of NH3 in H20.
A peak elutes from a column at 33.9 min, with a width at half height of 10.4s. How many theoretical plates does this column have?
Answer:
212724 plates
Explanation:
To solve this problem we use the formula:
N = 5.54 (tr/W₀.₅)²
Where
N is the number of theoretical plates,tr is the retention time (33.9 min)and W₀.₅ is the peak width at half height (10.4 s).We solve for N:
10.4 s⇒ 10.4 / 60 = 0.173 minN = 5.54 (33.9/0.173)²N = 212724 plates
2. In a chemistry experiment, 10 g of urea NH2CONH2 (s) is dissolved in 150 ml of water in a simple calorimeter. A
temperature decrease of 3.7°C is measured. Calculate the molar enthalpy of solution for urea.
Answer:In a chemistry experiment, 10g of urea, NH2CONH2 (s), is dissolved in 150 mL of water in a simple calorimeter. A temperature decrease of 3.7oC is measured. Calculate the molar enthalpy of solution (∆Hs). ... an ideal gas B if 0.622 g sample of gas B occupies a volume of 300 mL at 35 °C and 1.038 atm.
Explanation:
the molar ratio of cucl2 to Al should be
Answer:
1) The chemical equation is:
Al + CuCl2 ---> Cu + AlCl3
2) You have to balance the equation to state the coefficients:
2Al + 3CuCl2 ---> 3Cu + 2Al Cl3
3) Now the coefficients tell you the molar ratios.
2 mol Al : 3 mol CuCl2 : 3 mol Cu : 2 mol AlCl3
4) The molar ratio of CuCl2 to Al is:
3 mol Cu Cl2 / 2 mol Al = 3/2 = 1.5
Explanation:
what is the composition and structure of ionic compounds
Answer:
Sodium and chlorine ions come together to form sodium chloride or NaCl. The sodium atom in this compound loses an electron to become Na+, while the chlorine atom gains an electron to become Cl-. Together, they form a neutral compound because the ions balance each other out.
Explanation:
If MgCl2 (aq) has a molarity of 2.5 M, then the molarity of the Cl-1 ions is ____ M.
Answer:
molarity of Cl⁻ ions = 5.0 M
Explanation:
The molarity of a solution expresses the amount in moles of a solution present in a litre of solvent. Its unit is mol/L or mol/dm³ written as M.
MgCl₂ when dissolved to form an aqueous solution dissociates into positive and negative ions, Mg²⁺and Cl⁻ ions.
Equation of the dissociation of MgCl₂ in aqueous solution is given below:
MgCl₂(aq) -----> Mg²⁺(aq) + 2Cl⁻(aq)
1 mole of aqueous MgCl₂ produces 2 moles of chloride ions, Cl⁻
Molar concentration of MgCl₂(aq) = 2.5 M
Molarity of chloride ions = number of moles of Cl⁻ ions * molarity of MgCl₂
molarity of Cl⁻ ions = 2 * 2.5 M
molarity of Cl⁻ ions = 5.0 M
The specific heat of liquid bromine is 0.226 J/g-K. How much heat (J) is required to raise the temperature of 10.0 mL of bromine from 25.00 °C to 27.30 °C? The density of liquid bromine: 3.12 g/mL
Answer:
16.2 J
Explanation:
Step 1: Given data
Specific heat of liquid bromine (c): 0.226 J/g.KVolume of bromine (V): 10.0 mLInitial temperature: 25.00 °CFinal temperature: 27.30 °CDensity of bromine (ρ): 3.12 g/mLStep 2: Calculate the mass of bromine
The density is equal to the mass divided by the volume.
ρ = m/V
m = ρ × V
m = 3.12 g/mL × 10.0 mL
m = 31.2 g
Step 3: Calculate the change in the temperature (ΔT)
ΔT = 27.30 °C - 25.00 °C = 2.30 °C
The change in the temperature on the Celsius scale is equal to the change in the temperature on the Kelvin scale. Then, 2.30 °C = 2.30 K.
Step 4: Calculate the heat required (Q) to raise the temperature of the liquid bromine
We will use the following expression.
Q = c × m × ΔT
Q = 0.226 J/g.K × 31.2 g × 2.30 K
Q = 16.2 J
Which statement describes the conditions in which diamonds form?
Answer:
The answer to the question, 'which statement describe the formation of diamonds is option C. Diamond deposits are formed in the earth mantle and release to the earth surface by mean of volcanic eruptions which produce kimberlites. The formation of diamonds require very high temperatures and pressures. These conditions exist below the earth surface at the depth of about 150 kilometers and 1050 degree Celsius temperature.
Explanation:
Answer:
Diamond deposits are formed in the earth mantle and release to the earth surface by mean of volcanic eruptions which produce kimberlites
Explanation:
A::A represents
1. two lone pairs of electrons.
2. one lone pair of clectrons.
3. a double bond.
4. quadruple bond.
Answer:
1
Explanation:
because its to long just why its useless
6. What causes the phases of the moon?
Answer:
The rotation of the Earth.
A steel tank contains carbon dioxide at a pressure of 13.0 atm when the temperature is 34oC. What will be the internal gas pressure when the tank and its contents are heated to 100oC
Answer:
D. 15.8atm
Explanation:
Given parameters:
Initial pressure = 13atm
Initial temperature = 34°C = 34 + 273 = 307K
Final temperature = 100°C = 100 + 273 = 373K
Unknown:
Final pressure = ?
Solution:
To solve this problem, we apply a derivation of the combined gas law taking the volume as a constant.
The expression is shown mathematically below;
[tex]\frac{P_{1} }{T_{1} }[/tex] = [tex]\frac{P_{2} }{T_{2} }[/tex]
P and T pressure and temperature values
1 and 2 are initial and final states
Insert the parameters and solve for T₂;
[tex]\frac{13}{307}[/tex] = [tex]\frac{P_{2} }{373}[/tex]
P₂ = 15.8atm
The final pressure will be "15.8 atm".
According to the question,
Initial pressure,
[tex]P_1 = 13.0 \ atm[/tex]
Initial temperature,
[tex]T_1 = 34+273[/tex]
[tex]= 307 \ k[/tex]
Final temperature,
[tex]T_2 = 100+273[/tex]
[tex]= 372 \ k[/tex]
By using the Gay-Lussac's law of pressure and temperature, we get
→ [tex]\frac{P_1}{T_1} = \frac{P_2}{T_2}[/tex]
or,
→ [tex]P_2 = \frac{P_1\times T_2}{T_1}[/tex]
By substituting the values, we get
→ [tex]= \frac{13.0\times 373}{307}[/tex]
→ [tex]= 15.8 \ atm[/tex]
Thus the response above is right.
Learn more:
https://brainly.com/question/24191545
The equilibrium constant, Kc, for the following
reaction is 10.5 at 350 K.
2CH2Cl2(g) double arrow CH4(g) + CCl4(g)
If an equilibrium mixture of the three gases in a 12.7
L container at 350 K contains 0.205 mol of
CH2Cl2(g) and 0.414 mol of CH4, the equilibrium
concentration of CCl4 is......
mol.
Answer:
2CH2Cl2(g) Doublearrow CH4(g) + CCl4(g)
0.205 moles of CH2Cl2 is introduced. Let by the time an equilibrium is reached x moles each of CH4 and CCl4 are formed => remaining moles of CH2Cl2 are 0.205-x
i.e at equilibrium the concentration on CH2Cl2 is (0.205-2x) mol/L, CH4 is x mol/L, CCl4 is x mol/L
Now the equilibrium constant equation : K = [CH4][CCl4]/[CH2Cl2]^2 ([.] - stands for concentration of the term inside the bracket)
10.5 = x*x/(0.205-2x)^2
=> 10.5(4x^2-0.82x+0.042) = x^2
=>42x^2-8.61x+0.441=x^2
=>41x^2-8.61x+0.441 = 0
This is a Quadratic in x, solving for the roots, we get x = 0.0886 , x = 0.121
The second solution for x will lead 0.205-2x to become negative, so is an infeasible solution.
Therefore equilibrium concentrations of the products and reactants correspond to x=0.0886 and they are , [CH2Cl2] = 0.205-2*0.0886 =0.0278 mol/L , [CH4] = 0.0886 mol/L , [CCl4] = 0.0886 mol/L
Which compounds are organic?
a. CO2
b. NaCl
c. C6 H12 O6
d. CH2P (C6H5)3
Answer:
All of them except NaCl
Explanation:
Organic compounds are compound that basically contain carbon-hydogen bonds. Salt (NaCl) doesn't have carbon, and the rest does. So I think that A, C, and D are the answers.
I hope this helps!
Which body of water will have a greater influence on an area?
A. river
B. lake
C. stream
D. ocean
Answer:
The correct option is A
Explanation:
Water from a river is used for many activities in a community. These activities could include (but not limited to) tourism, drinking for animals, local transport, irrigation for nearby farming, recreation (as in swimming), habitat for some living organisms among others. Rivers are not limited by what limits the influence of oceans such as taste (it's saltiness, which cannot be used in farming also) and wave current.
Marigold, Inc. uses activity-based costing as the basis for information to set prices for its six lines of seasonal coats.
Activity Cost Pools Estimated Overhead Estimated Use of Cost Drivers per Activity
Designing $445,200 10,600 designer hours
Sizing and cutting 4,081,200 152,000 machine hours
Stitching and trimming 1,491,000 84,000 labor hours
Wrapping and packing 346,500 33,000 finished units
Compute the activity-based overhead rates using the following budgeted data for each of the activity cost pools.
Designing
Sizing and cutting
Stitching and trimming
Wrapping and packing
Answer:
Designing= $42 per designer hour
Sizing and cutting= $26.85 per machine hour
Stitching and trimming= $17.75 per labor hour
Wrapping and packing= $10.5 finished unit
Explanation:
To calculate the activity-based overhead rates, we need to use the following formula:
Predetermined manufacturing overhead rate= total estimated overhead costs for the period/ total amount of allocation base
Designing= 445,200/10,600= $42 per designer hour
Sizing and cutting= 4,081,200/152,000= $26.85 per machine hour
Stitching and trimming= 1,491,000/84,000= $17.75 per labor hour
Wrapping and packing= 346,500/33,000= $10.5 finished unit
What mass of Al(OH)3 is needed to completely react with 17.9g of HCl?
Answer:
12.8 g
Explanation:
Step 1: Write the balanced neutralization reaction
Al(OH)₃ + 3 HCl ⇒ AlCl₃ + 3 H₂O
Step 2: Calculate the moles corresponding to 17.9 g of HCl
The molar mass of HCl is 36.46 g/mol.
17.9 g × 1 mol/36.46 g = 0.491 mol
Step 3: Calculate the moles of Al(OH)₃ that completely react with 0.491 moles of HCl
The molar ratio of Al(OH)₃ to HCl is 1:3. The reacting moles of Al(OH)₃ are 1/3 × 0.491 mol = 0.164 mol
Step 4: Calculate the mass corresponding to 0.164 moles of Al(OH)₃
The molar mass of Al(OH)₃ is 78.00 g/mol.
0.164 mol × 78.00 g/mol = 12.8 g