Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
Explanation:
Answer:
Fluorine
Fluorine is the element in question, as its atomic number is 9 . You would name this particular isotope using the mass number. It would be called fluorine-19.
The compound 2-hydroxybiphenyl (o-phenylphenol) boils at 286 °C under 101.325 kPa and at 145 °C under a reduced pressure of
14 Torr. Calculate the value of the molar enthalpy of vaporization. Compare this value to that given in the CRC Handbook.
Answer: [tex]\Delta H_{vap}[/tex] = 55.1 kJ/mol
Explanation: Molar Enthalpy of Vaporization([tex]\Delta H_{vap}[/tex] ) is the energy needed to change 1 mol of a substance from liquid to gas at constant temperature and pressure.
For the 2-hydroxybiphenyl, there two temperatures and 2 pressures. In this case, use Clausius-Clapeyron equation:
[tex]ln\frac{P_{2}}{P_{1}}=\frac{\Delta H_{vap}}{R} (\frac{1}{T_{1}}-\frac{1}{T_{2}} )[/tex]
[tex]\Delta H_{vap}[/tex] is in J/mol:
1) Temperature in K
[tex]T_{1}=[/tex] 286 +273 = 559K
[tex]T_{2}[/tex] = 145 + 273 = 418K
2) Both pressure in Pa
[tex]P_{1}[/tex] = 101325Pa
[tex]P_{2}[/tex] = 14*133 = 1862Pa
Since molar enthalpy is in Joules, gas constant R is 8.3145J/mol.K
Replacing into the equation:
[tex]ln\frac{1862}{101325}}=\frac{\Delta H_{vap}}{8.3145} (\frac{1}{559}-\frac{1}{418} )[/tex]
[tex]ln(0.0184)=\frac{\Delta H_{vap}}{8.3145} (\frac{141}{233662} )[/tex]
[tex]\Delta H_{vap}=\frac{-3.9954*1942782.7}{-141}[/tex]
[tex]\Delta H_{vap}=55051.02[/tex]
[tex]\Delta H_{vap}=55051.02[/tex]
[tex]\Delta H_{vap}=55.1[/tex] kJ/mol
Using those values, molar enthalpy is 55.1 kJ/mol
Comparing to the CRC Handbook, which is [tex]\Delta H_{vap}=71[/tex] kJ/mol:
[tex]\frac{55.1}{71}[/tex] = 0.78
The calculated value is 0.78 times less than the CRC Handbook.
is a light bulb chemical or physical change. State evidence why
Answer:
It is a chemical change.
Explanation:
When the electricity is off, the filament cools down to its original physical state. This physical process repeats every time the light is turned on and off. However, if the bulb is cracked and air is introduced, the oxygen in the air reacts with the tungsten filament which then undergoes a chemical change.
how do you convert wavelength to frequency?
Answer:
Image result for how do you convert wavelength to frequency?
How do you calculate energy from wavelength?
Convert your wavelength into meters.
Divide the speed of light, ~300,000,000 m/s, by the wavelength in m. This gives you the wave's frequency.
Multiply the frequency by Planck's constant, 6.626 x 10-34. The result is the waves energy in joules (J).
Explanation:
Discuss and Implement the Price Adjustment Strategies in the current market. Apply each strategy with 3 examples along with the picture. This question is related to Marketing.
Answer:
There are many different price adjustment strategies which can be implemented in the current market.
Explanation:
Psychological pricing:
Psychological pricing is a strategy in which the price of a product is displayed with mostly one cent difference so the whole number shown is less by $1 and this difference can get higher if the price of the product is more.
Example 1: The price for a toy in a toy shop is $4.99, if rounded this will be $5 but the whole number visible is $4.
Example 2: The price of a laptop is $193, this again is nearly $200 but the price is reduced by $7 in order to influence their customers into buying the product.
Example 3: The price of a car is $35,995, this again is about $36,000 but the buyer may be influenced by this technique and result in purchasing the product with such price.
Geographical Pricing:
Geographical pricing is a strategy where different prices are charged in different outlets, this strategy is made keeping in mind the purchasing power of the locality, if the local people can pay higher price for a product then the price is high there but same product may have a lower price in an area where people can not pay high price.
Example 1: Price of a T-shirt is $15 in a posh area while the price of the same T-shirt is $5 in an area with poor locality.
Example 2: Price of a hair brush is $10 in a poor area while the same brush is available in a posh area at a rate of $35.
Example 3: Price for a food item is $6 in a restaurant in posh area while the same burger is available for $3 in a restaurant in a poor area.
2. You are tasked with calculating the average weight of kindergartners in a class of
21 students. Their weights range from a low of 40.5 lbs to a high of 58.6 lbs.
How many significant figures should be in the average that you find?
I WILL mARK U BRAINLLYIST
Scientists in a particular fieScientists in a particular field strive for the same quality of work because they know their peers will be reviewing their scientific claims. What does this review process help ensure?
standards of the profession
publication in scientific journals
resistance to new information
access to university databases
Discuss the effect of changing the flow tube radius on flow rate.
Answer:
The flow rate of a tube is the volume of fluid flowing through the tube per unit time. The flowrate is proportional to the product of the velocity of the fluid through the tube, and the cross-sectional area of the tube.
That is
Q = AV
where
A is the area of the tube
V is the velocity of the tube
The cross-sectional area of the tube is proportional to the radius of the tube. From the above equation, we can deduce that if the velocity of the fluid flowing through the tube is held constant, the flowrate of the fluid through the tube will increase with an increase in the radius of the tube, and it will decrease with a decrease in the radius of the tube.
Given that the specific heat of chromium is 0.455J/g∙K find the final temperature after 35.9J of energy is removed from 11.7g of chromium at 28.5°C.
Answer:
[tex]T_2=35.2\°C[/tex]
Explanation:
Hello,
In this case, since the heat is computed in terms of mass, specific heat and temperature as follows:
[tex]Q=mCp(T_2-T_1)[/tex]
In such a way, for the given heat, we obtain the following temperature:
[tex]T_2=T_1+\frac{Q}{mCp}\\ \\T_2=28.5\°C+\frac{35.9J}{11.7g*0.455\frac{J}{g\°C} }\\ \\T_2=35.2\°C[/tex]
Best regards.
100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. What is the new concentration of the solution
Answer:
0.1 M
Explanation:
The following data were obtained from the question:
Initial volume (V1) = 100 mL
Initial concentration (C1) = 0.5 M
Final volume (V2) = 500 mL
Final concentration (C2) =?
Using the dilution formula C1V1 = C2V2, the new concentration of the solution can be obtained as follow:
C1V1 = C2V2
0.5 × 100 = C2 × 500
50 = C2 × 500
Divide both side by 500
C2 = 50/500
C2 = 0.1 M
Therefore, the new concentration of the solution is 0.1 M
The new concentration of the solution of KBr that was diluted to 500mL is 0.1M
HOW TO CALCULATE CONCENTRATION:
The concentration of solution that was diluted can be calculated using the formula as follows:C1V1 = C2V2Where:
C1 = original concentration (M)C2 = diluted concentration (M)V1 = original volume (mL)V2 = diluted volume (mL)According to this question, 100.0 mL of a 0.500 M solution of KBr is diluted to 500.0 mL. The new concentration can be calculated as follows:0.500 × 100 = C2 × 50050 = 500C2C2 = 50 ÷ 500C2 = 0.1MTherefore, the new concentration of the solution of KBr that was diluted to 500mL is 0.1M.Learn more at: https://brainly.com/question/10720472?referrer=searchResults
Alkynes are reduced to trans alkenes by a process called dissolving metal reduction. The reaction uses sodium or lithium metal as the reducing agent and liquid ammonia as the solvent. The method is specific in the formation of trans alkenes from alkynes. The method involves two successive transfers of single electrons from the alkali metal to the triple bond, with abstraction of protons from the ammonia solvent.Draw curved arrows to show the movement of electrons in this step of the mechanism.Arrow-pushing Instructions
Answer:
Explanation:
The movement of the electrons is illustrated in the picture attached to this answer. It is a four-step reaction mechanism.
First STEP: The first step involves the transfer of an electron from sodium to form a radical anion.
Second STEP: This radical anion then removes a proton/hydrogen from ammonia in a bid to neutralize itself (hence the hydrogen becomes bonded to the anion).
Third STEP: The sodium (from NaNH₂ formed) transfers an electron again to produce a vinyl carbanion.
Fourth STEP: The carbanion then removes a proton/hydrogen from ammonia (like in the second step) to form a neutral trans-alkene.
NOTE: The circled numbers denote each step while the mechanism on the left represents the use of any alkyl group (R and R') while the mechanism on the right assumes both alkyl groups are methyl. Hence, 2-butyne started the reaction and the final product was trans-2-butene.
Why are atoms usually portrayed as spheres when most orbitals are not spherically shaped?
a. The shape of an atom depends on the shape of its nucleus, not on the shape of its orbitals.
b. The shape of an atom depends on the shape of the outer orbital which always spherical
c. The shape of an atom is obtained by superimposing all of its orbitals.
d. The shape of an atom is not important so it is easier to treat atoms as spheres.
Answer:
The shape of an atom is not important so it is easier to treat atoms as spheres.
Explanation:
In considering the shape of an atom, we do not consider the shape of the orbitals individually.
Hence, we do not seek to determine the exact shape of the atom, rather we simply treat the atom as spheres. Even though most orbitals are not spherically shaped.
an object has a mass of 14g and a volume 3.5 mL. what is the density of the object ?
Given :
Mass of object , M = 14 g .
Volume of object , V = 3.5 mL .
To Find :
The density of the object .
Solution :
Density of an object is given by :
[tex]Density=\dfrac{Mass}{Volume}\\\\\rho=\dfrac{M}{V}\\\\\rho=\dfrac{14}{3.5}\ g/mL\\\\\rho=4\ g/mL[/tex]
Therefore , the density is 4 g/mL .
Hence , this is the required solution .
Describe the evidence for Mercury having a molten iron core
Write balanced molecular and net ionic equations for the following metathesis (double displacement) reactions, if they occur. If no reaction occurs, write NR on the product side. All reactants are aqueous. Phase subscripts must be included to indicate what products stay in solution (aq), and what products precipitate (s).
a. zinc acetate + sodium carbonate
b. barium nitrate + sodium sulfate
c. lead (II) nitrate + sodium sulfate
d. zinc acetate + sodium sulfate
e. barium nitrate+ potassium iodide
f. lead (I) nitrate+ potassium iodide
g. zinc acetate + potassium iodide
Answer:
attached below is the required solution
Explanation:
A) Zinc acetate + Sodium carbonate
B) barium nitrate + sodium sulfate
C ) lead ( II ) nitrate + sodium sulfate
D) Zinc acetate + sodium sulfate
E) barium nitrate + potassium iodide
F) Lead ( I ) nitrate + potassium iodide
G) Zinc acetate + potassium iodide
A net ionic equation shows the ions that underwent change in a reaction hence it excludes the spectator ions.
A metathesis reaction is one which the cations exchange anion partners in the products. A general example of a methathesis reaction is AX + BY ---> AY + BX.
The molecular and net ionic equation for the reactions are;
1) Zn(CH3COO)2(aq) + Na2CO3(aq) -----> ZnCO3(s) + 2CH3COONa(aq)
Net ionic equation; Zn^2+(aq) + CO3^2-(aq) ------> ZnCO3(s)
2) Ba(NO3)2(aq) + Na2SO4(aq) ------> BaSO4(s) + 2NaNO3(aq)
Net ionic equation; Ba^2+(aq) + SO4^2-(aq) ------> BaSO4(s)
3) Pb(NO3)2(aq) + Na2SO4(aq) ------> PbSO4(s) + 2NaNO3(aq)
Net ionic equation; Pb^2+(aq) + SO4^2-(aq) ------> PbSO4(s)
4) Zn(CH3COO)2(aq) + Na2SO4(aq) ------> ZnSO4(s) + 2CH3COONa(aq)
Net ionic equation: Zn^2+(aq) + SO4^2-(aq) ------> ZnSO4(s)
5) Ba(NO3)2(aq) + 2KI(aq) ------> 2KNO3(aq) + BaI2(aq)
There is no net ionic equation for this reaction.
6) Pb(NO3)2(aq) + 2KI(aq) -------> PbI2(s) + 2NaNO3(aq)
Net ionic equation: Pb^2+(aq) + 2I^-(aq) -----> PbI2(s)
7) Zn(CH3COO)2(aq) + 2KI(aq) -----> ZnI2(aq) + 2CH3COOK(aq)
There is no net ionic equation for this reaction
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A 0.500 g sample of tin (Sn) is reacted with oxygen to give 0.534 g of product. What is the empirical formula of the oxide?
Answer:
[tex]Sn_2O[/tex]
Explanation:
Hello,
In this case, given the mass of the sample and mass of tin we can compute the mass of oxygen via:
[tex]m_O=0.534g-0.500g=0.034g[/tex]
Thus, by using the atomic bas of tin and oxygen we can compute their moles:
[tex]n_{Sn}=0.500gSn*\frac{1molSn}{118.8gSn} =0.00421mol\\\\n_O=0.034gO*\frac{1molO}{16gO}=0.002125mol[/tex]
Next, we need to divide both moles by the moles of oxygen as those are the smallest in order to compute the subscript in the chemical reaction:
[tex]Sn=\frac{0.00421}{0.002125}=2\\ \\O=\frac{0.002125}{0.002125}= 1[/tex]
Therefore, empirical formula of the oxide should be:
[tex]Sn_2O[/tex]
Best regards.
Which of the following is equal to an impulse of 18 units?
O A. Force = 10, time = 2
B. Force = 0.1, time = 18
O C. Force = 6, time = 3
OD. Force = 7, time = 3
Answer:
the answer is C. this is because 6 times 3 is 18
What was Albert Einstein's contribution to our understanding of the
photoelectric effect?
A. He described the relationship between energy and mass.
B. He described photons as little packets of electrons.
C. He described electricity as moving electrons.
D. He described light as little packets called photons.
Answer: The Answer Is D, He described light as little packets called photons.
Explanation:
The contribution of Albert Einstein to our understanding of the photoelectric effect is he described light as little packets called photons. The correct option is D.
Who is Albert Einstein?The theory of relativity, which Albert Einstein developed and is rightfully famous for, transformed our understanding of space, time, gravity, and the cosmos.
Along with his work on relativity, the physicist established the scientific principles behind items like paper towels, lasers, and other everyday items.
Since Einstein first suggested using the use of light quanta to clarify the photoelectric impact, quantum theory accurately portrays the photoelectric impact. The quantum theory of radiation gives this concept a formal formulation.
Therefore, the correct option is D. He described light as little packets called photons.
To learn more about Albert Einstein, refer to the below link:
https://brainly.com/question/4229446
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Helium is more reactive than magnesium.
TRUE
FALSE
Answer: FALSE
Explanation: Magnesium is more reactive.
Hope this helps!
Answer:
False
Explanation:
Magnesium is more reactive.
PLEASE ANWSER FAST! Gus is performing an experiment on cells. First he places the cells in a container of water and salt. When he checks some of the cells under a microscope, he sees that they are beginning to shrivel. What would most likely stop the cells in the liquid from shriveling? adding more water to the container adding more salt to the container increasing the number of cells in the container decreasing the number of cells in the container
Answer:
adding more water to the container
Explanation: because it would cause it to soak up the fluid to created a substance again
Answer:
adding more water to the container and iflamates the cells
Explanation:
What particle(s) of an atom would NOT found in the nucleus?
Electrons
proton
neutron
neutrons and electrons
Answer:
Electrons, they circle the nucleus.
Consider this equilibrium reaction at 400 K. Br2(g)+Cl2(g)↽−−⇀2BrCl(g)Kc=7.0 If the composition of the reaction mixture at 400 K is [BrCl]=0.00415 M, [Br2]=0.00366 M, and [Cl2]=0.000672 M, what is the reaction quotient, ???? ? ????= How is the reaction quotient related to the equilibrium constant, Kc, for this reaction?
Answer:
Q = 7.0
Q = kc. The reaction is in equilibrium
Explanation:
Based on the reaction:
Br₂ + Cl₂ ⇄ 2BrCl
Equilibrium constant of the reaction, kc, is the ratio of equilibrium concentrations products over reactants powered to its reaction coefficient:
Kc = [BrCl]² / [Br₂] [Cl₂] = 7.0
Now, reaction quotient, Q, is write as the same Kc but the concentrations are actual concentrations:
Q = [BrCl]² / [Br₂] [Cl₂]
Replacing:
Q = [0.00415M]² / [0.00366M] [0.000672M]
Q = 7.0
Now, as Q = Kc = 7.0, the reaction mixture is in equilibrium
john has a solution with a pH of 12.21. what is the hydrogen ion concentration of this solution?
Answer:
In this way, ph is determined by hydrogen ion concentration . In the case of neutral solution [H+] =10-7 which we call a ph of 7. This means, for example, that a hydrogen-ion concentration of a solution with a ph of 4 is 10-4 mol/l, meaning it contains 0.0001 mole of hydrogen ion in a solution of 1 liter.
what is the balanced chemical equation when solid calcium oxide and carbon dioxide gas are formed by the decomposition of solid calcium carbonate (CaCO3)
Is condensation phyiscal change
Answer:
condensation is the change of the physical state of matter from the gas phase to the liquid phase :)
Explanation:
Answer:
Yes.
Explanation:
Condensation is the change of physical state of matter from gas to liquid.
If the density of a diamond is 3.5g/cm3, what would be the mass of a diamond whose volume is 0.5 cm3?
Answer:
1.75 g
Explanation:
as density ×volume =mass
3.5×0.5=mass
mass=1.75 g
plz mark as brainliest if it helps
The mass of the diamond which has a density of 3.5g/cm3 is [tex]1.75kg[/tex]
Density is given as:[tex]3.5g/cm3[/tex]having a volume of [tex]0.5 cm^3[/tex]But we know that Density can be regarded as the the ratio of mass to that of volume of that particular object.let us represent this mathematically as;[tex]Density=[/tex] [tex]\frac{ mass }{ volume }[/tex]we can make Mass the subject of the formula to find the mass[tex]Mass= ( Density * volume)[/tex]Then let us substitute the give value, then we will have[tex]= ( 3.5*0.5)[/tex][tex]= 1.75kg[/tex]
Therefore, the mass is[tex]1.75kg[/tex]
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What is the purpose of keeping a running list of new vocabulary words?
A. To make it easier to decode the word when you see it again
B. To provide an easy-to-remember picture associated with the word
C. To make it easier to remember and use new words
D. To allow you to critically evaluate every new word you come
across
Shjajfbcjahaixhfjwnzhsbsjxjdbxbsjzjfbwnznsnwnnsndndnwnbwjshsbdbdndnndndndbxbxnsnsn
Answer:
C
Explanation:
As C would be the wisest choice as being able to remember and use more words than the average human not only opens up your vocabulary but also your chances of writing a better essay using said words.
Answer:
C
Explanation:
Makes it easier to remember and use new words
What is the final volume of argon gas if 2.5 L at 94.0 kPa is compressed to a pressure of 207 kPa
Answer:
1.1 L
Explanation:
Volume and pressure are inversly proportional to each other meaning as volume increase, pressure decreases or the other way around. Use the equation V1P1=V2P2. So, it'll be (2.5L)(94.0kpa)=(207kPa)(V2). Thereby it is (2.5*94.0)/207= V2 = 1.1L. Don't forget your sigfigs which will be to 2 sigs.
Which of the following experimental methods cannot be used to measure the rate of a reaction? Group of answer choices measurement of the absorbance of a colored reactant with time measurement of the change in the partial pressure of a gas-phase product over time measurement of the equilibrium concentration of an acidic product via titration with a strong base measurement of the absorbance of a colored product with time measurement of the change in the partial pressure of a gas-phase reactant over time
Answer:
measurement of the equilibrium concentration of an acidic product via titration with a strong base
Explanation:
The rate at which a reaction proceeds refers to how quickly the reaction is occuring. In other words, it is how quickly the reactants are changing to the products. According to the question, the rate of a reaction can be measured experimentally using the reactants' or products' properties e.g volume, pressure etc.
Since reactions must involve reactants and products, the manner in which either the reactants or products changes over time can be measured. For example; measurement of the absorbance of a colored reactant or product with time, measurement of the change in the partial pressure of a gas-phase reactant or product over time can be used.
However, a measurement of the equilibrium concentration of an acidic product via titration with a strong base will not tell us how fast the reaction is going because it is in an EQUILIBRIUM state i.e. reaction is occuring at an equal rate
For a trip to the Moon, a rocket must lift off from
Earth's surface. Suppose it takes 5 minutes for the
rocket to reach a velocity of 6,000 m/s upward from
a starting velocity of 0 m/s. What is the rocket's
acceleration?
Answer:
20 m/s^2
Explanation:
given,
final velocity (v) = 6000m/s
initial velocity (u) = 0m/s
time taken (t) = 5 minutes
= 5×60second
= 300second
acceleration(a) = ?
we know that,
a = (v-u)/t
= (6000-0)/300
= 20 m/s^2
1- Science that deals with the identification and quantification of the components of material systems
A)Analytical Science
B)Biochemistry
C)Organic Chemistry
D) Inorganic Chemistry
Q1-(30 Marks) Choose the correct answer
Answer:
Analytical science
Explanation: