Answer:D all of these
Explanation:
I just did it and that’s the correct answer
.
5.0 mg of radioactive nobelium-253 was removed from the reactor to be
used in an experiment. It took 291 seconds (just under 5 minutes) to
get the sample from the reactor to the laboratory. How many milligrams
of nobelium-253 remained upon arrival to the laboratory? The half-life
of nobelium-253 is 97 seconds.
Answer:
Explanation:
Half life of Nobelium-253 is 97 seconds . That means after every 97 seconds half of the Nobelium amount will be disintegrated .
Time taken in bringing the sample to laboratory = 291 seconds
291 second = 291 / 97 half life
n = 3
N = [tex]N_0 (\frac{1}{2})^n[/tex]
N₀ is original mass , N is mass after n number of half life.
N = 5 mg x [tex](\frac{1}{2})^3[/tex]
= .625 mg
Only 0.625 mg of Nobelium-253 will be left .
Silver (1) oxide → silver + oxygen gas
Answer: come on lets link can do what i do
It takes 300 N to move a box 10 meters in 10 seconds. How much power is
required?
A. 30,000 W
B. 100 W
C. 3,000 J
D. 300 W
Plz help
Answer:
Power, P = 300 W
Explanation:
We have,
Force acting on the box to take it is 300 N
It is moved to a distance of 10 m in 10 seconds
It is required to find the power required to move the box. The rate at which work is done is called power required by an object. It can be given by the formula as follows :
[tex]P=\dfrac{W}{t}\\\\P=\dfrac{Fd}{t}\\\\P=\dfrac{300\times 10}{10}\\\\P=300\ W[/tex]
So, the power required is 300 W.
At constant temperature and moles, what happens to the pressure of a gas
as the volume of that gas increases? *
Answer:
Avagadro's Law- Gives the relationship between volume and amount of gas in moles when pressure and temperature are held constant. If the amount of gas in a container is increased, the volume increases. ... This means more impacts on the walls of the container and an increase in the pressure.
Explanation:
Describe the catenation property of carbon by illustrating the formation of a straight chain and branched chain compounds
Answer:
Catenation refers to the ability of an atom to link to other atoms of the same kind to form a chain.
Explanation:
Catenation is the binding of an element to itself through covalent bonds to form chain or ring .Catenation can also be defined as the self-linking of atoms of an element to form chains and rings. This definition can be extended to include the formation of layers like two-dimensional catenation and space lattices like three-dimensional catenation. Thus, we can boldly say that, Catenation occurs when atoms of the same element covalently bond to one another to create a chain or ring.
Catenation occurs most readily in carbon, forming covalent bonds to and longer chains and structures with other carbon atoms. This is why the vast number of organic compounds are found in nature. Carbon is best known for its catenation properties, with the analysis of catenated carbon structures in organic chemistry.
Carbon is by no means the only element capable of forming such catenae, however, and several other main group elements are capable of forming a wide range of catenae, including silicon, sulfur, and boron. In group 14, the high bond energy of carbon makes it able to self-link almost indefinitely when compared with other members of the group which form only a few bonds to other atoms of the same element.
In a different experiment, the student uses a calorimeter which is perfectly insulated. She fills the calorimeter with 100.0 g of 25.00°C dilute HCl solution and adds 0.594 g Mg metal (24.3 g/mol). The final temperature of the apparatus comes to 41.83°C. Remember, the solution is made-up of the solute and the solvent. The specific heat for magnesium is negligible compared to the aqueous solution. What is the Molar Heat of Enthalpy for this reaction?
Answer:
Explanation:
Mg + 2HCl = Mg Cl₂ + H₂
.594 g = .594 / 24.3
= .02444 mole
Heat evolved = msΔ T , m is mass of water ( solvant ) , s is specific heat of water , Δ T is rise in temperature
= 100 x 4.2 x ( 41.83 - 25 )
= 7068.6 J
.02444 mole of Mg evolves 7068.6 J of heat
1 mole of Mg evolves 7068.6 /.02444 J
= 289222.6 J
= 289 kJ .
Molar heat enthalpy = 289 kJ .
How are plastic containers different from paper containers? How are they the same?
Answer:
Paper is Not Reuseable like plastic.
Explanation:
How to make isopropyl alcohol
Answer:
.It is easily synthesized from the reaction of propylene with sulfuric acid, followed by hydrolysis. Isopropyl alcohol (2-propanol) is made by indirect hydration of propylene (CH2CHCH3).… In some cases the hydration of propylene is carried out in one step, using water and a catalyst at high pressure.
Hope it'll help!
stay safe:)
6. Bacteriorhodopsin is an integral membrane protein that uses solar energy (absorbed by its retinal chromophore) to pump protons out of the cell against an electrochemical gradient. Re-entry of the protons into the cell (down the gradient through its ATPase) is then used to drive the synthesis of ATP from ADP and Pi. Consider the following conditions: intracellular pH is 9.4 and extracellular pH is 6.4, and there is a transmembrane electrical gradient of 120 mV (negative inside). The concentration of intracellular [ATP] = 1 mM, [ADP] = 50 µM, and [Pi] = 2 mM, and G° for ATP hydrolysis is -30.5 kJ/mol. Temperature is 27 °C. a. What is the energy cost of pumping one mole of H+ out of the cell? b. What is the minimal number of H+ that must re-enter the cell through the ATPase to provide sufficient energy to synthesize each ATP? Explain how you arrived at this answer quantitatively, of course.
Answer:
Explanation:
Hello!
a)
You have an integral membrane protein (Bacteriorhodopsin) that uses solar energy to pump protons out of the cell against its electrochemical gradient.
To calculate the energy needed by the protein to pump one molecule out of the cell you need to apply the free energy difference equation for a charged molecule:
ΔG= 2.303RTlog₁₀[tex](\frac{[H^+]out}{[H^+]in})[/tex]+zFΔV
Where
ΔG= free energy difference per molecule transferred from the inside to the outside
R= gas constant 8.315*10⁻³ kJ/mol
T= Temperature in Kelvin (273.15 + TºC)
z= Valency of the ion (ej Na⁺ is z= +1 and Cl⁻ is z= -1)
F= Faraday constant 96.5 kJ/V*mol
ΔV= membrane potential (Volts)
The information you have is:
Intracellular pH= 9.4
Extracellular pH= 6.4
ΔV= 120 mV
Temperature 27ºC
Using the values of pH you can calculate the intracellular and extracellular proton concentrations:
Remember the pH of a solution is calculated as pH=-log[H⁺] so if you reverse the logarithm, you'll find the concentration of protons:
b= logₐ C ⇒ C= aᵇ
[H⁺]intracelular= 10⁻⁹'⁴
[H⁺]extracelular= 10⁻⁶'⁴
Now you need to match the units of the temperature and electrical gradient to the ones in the equation:
The temperature needs to ve in Kelvin: T= 273.15 + 27ºC= 300.15K
The electrical gradients need to be in Volts: ΔV= 120 mV= 0.12V
Now you can replace the data in the formula and calculate how much energy is needed to pump one proton outside the cell:
ΔG= 2.303RTlog₁₀[tex](\frac{[H^+]out}{[H^+]in})[/tex]+zFΔV= 2.303*( 8.315*10⁻³ kJ/mol)*300.15K*log[tex](\frac{10^{-6.4}}{ 10^{-9.4}} )[/tex]+(+1)*96.5 kJ/V*mol*0.12V= 28.82 kJ/mol
It costs 28.82 kJ/mol to pump one mole of H⁺ outside the cell.
b)
To synthesize one molecule of ATP the ATP synthase uses the electrical gradient produced by the spontaneous pass of protons through the membrane. This process is called the proton-motive force.
The ATP synthase consists of two subunits F₀ and F₁ with a rotational motor mechanism that allows it to produce and release ATP.
F₁ has the subunits α, β, σ, γ, ε in charge of synthesizing ATP
F₀ is a proton pore, made of 3 subunits a, b and c. 6 subunits c make up the transmembrane ring in charge of rotation, this ring is connected to the subunits γ and ε. Each time a proton passes, it makes the ring rotate which makes the subunits γ rotate.
Each time the subunit γ rotates 360º, 3 ATP molecules are synthesized and freed. A full rotation of γ means that the c-ring also made a full rotation (for this you need one proton per subunit)
If the ring has 6 c-subunits and, then each ATP molecule needs 6/3= 2 protons to need to pass for each ATP molecule.
I hope this helps!
Please real answers only , 100 pts and brainliest .
what is A , B and C?
Answer:
A = 1.2L
B = 506.6 torr
C = 13.5 °C
Answer:
A = 1.2L B = 506.6 torr and C = 13.5 °C
have a nice day :)
When Mrs. Green describes the physical properties of matter she said that physical properties often concern changes in state, One
physical property that does not describe a change in state is
A)
density
B)
evaporation
C)
freezing
D)
melting
Answer:
density
Explanation:
Density is an important measurement. It has an unit: g/mL or kg/L, ...
Evaporation, freezing, melting are the processes in which the substances change their states. Other processes are: condensation, sublimation, deposition.
...
Hope this answer can help you. Have a nice day!
What is the molality of a solution that contains 31.0 g HCl in 5.00 kg water? (molar mass of
HCI = 36.46 g/mol)
Answer:
0.17M
Explanation:
5kg of water contains 5 liters as the density of water is 1000 [tex]kgm^{-3}[/tex]
Therefore one liter of water contains 31/5=6.2g of HCl
Molality of the solution = 6.2/36.46 =0.17M
Two liquids, A and B, have equal masses and equal initial temperatures. Each is heated for the same length of time over identical burners. Afterward, liquid A is hotter than liquid B. Which has the larger specific heat? Two liquids, A and B, have equal masses and equal initial temperatures. Each is heated for the same length of time over identical burners. Afterward, liquid A is hotter than liquid B. Which has the larger specific heat? Liquid A. There's not enough information to tell. Liquid B.
Answer:
Liquid A.
Explanation:
Specific heat is defined as the amount of heat required per unit of mass to raise the temperature by one degree celsius.
When two liquids are heated, the liquid with larger specific heat is the one which is hotter. That is because is required more energy to decrease its temperature by 1°C.
Thus, in the problem, liquid A has the larger specific heat
A container is filled with 10 mol of gas and the pressure (Pi) is measured. If 5 mol are removed, what is the new pressure (Pf)?
Answer:
1/2 of the Pi
Explanation:
PV = nRT
we are going to assume the only things changing are pressure and number of mols, so we change the formula and substitute the variables to make it what we are looking for
[tex]\frac{Pi}{ni} = \frac{Pf}{nf}[/tex]
then we will assume Pi as 1 as it is not given, so we can state it easier
[tex]\frac{1atm}{10mol} = \frac{xatm}{5mol}[/tex]
then either cross multiply or just work it out to be
[tex]\frac{1}{2}[/tex] which we can say as "half of the initial pressure" as no number is given for initial pressure
Which factor would slow down a chemical reaction? (Choose all that apply)
A)Adding an inhibitor
B)Decreasing temperature
C)Decreasing particle size
D)Increasing particle size
Answer:
(decreasing particle size) C
Explanation: That is one of the answers, if there are more I am sorry.
Which of the following are peninsulas in Southeast Asia?
A.
the Miramar Peninsula and the Tasmanian Peninsula
B.
the Indochinese Peninsula and the Malay Peninsula
C.
the Philippine Peninsula and the Vietnam Peninsula
D.
the Irrawaddy Peninsula and the Mekong Peninsula
Answer:
B.
Explanation:
Answer:
B
Explanation:
Which statements describe inorganic compounds? Check all that apply
Inorganic compounds contain carbon
Inorganic compounds usually lack carbon
Inorganic compounds are not associated with or made from living things,
Inorganic compounds include fruits and vegetables,
Inorganic compounds include salt and water
Answer:
b, c, e
Explanation:
Inorganic compounds usually lack carbon.
Inorganic compounds are not associated with or made from living things.
Inorganic compounds include salt and water.
Answer:
yes the answer id bce
Explanation:
1. A 99.8 mL sample of a solution that is 12.0% KI by mass (d: 1.093 g/mL) is added to 96.7 mL of another solution that is 14.0% Pb(NO3)2 by mass (d: 1.134 g/mL). How many grams of PbI2 should form?
Pb(NO3)2(aq) + 2 KI(aq) PbI2(s) + 2 KNO3(aq)
Answer:
[tex]m_{PbI_2}=18.2gPbI_2[/tex]
Explanation:
Hello,
In this case, we write the reaction again:
[tex]Pb(NO_3)_2(aq) + 2 KI(aq)\rightarrow PbI_2(s) + 2 KNO_3(aq)[/tex]
In such a way, the first thing we do is to compute the reacting moles of lead (II) nitrate and potassium iodide, by using the concentration, volumes, densities and molar masses, 331.2 g/mol and 166.0 g/mol respectively:
[tex]n_{Pb(NO_3)_2}=\frac{0.14gPb(NO_3)_2}{1g\ sln}*\frac{1molPb(NO_3)_2}{331.2gPb(NO_3)_2} *\frac{1.134g\ sln}{1mL\ sln} *96.7mL\ sln\\\\n_{Pb(NO_3)_2}=0.04635molPb(NO_3)_2\\\\n_{KI}=\frac{0.12gKI}{1g\ sln}*\frac{1molKI}{166.0gKI} *\frac{1.093g\ sln}{1mL\ sln} *99.8mL\ sln\\\\n_{KI}=0.07885molKI[/tex]
Next, as lead (II) nitrate and potassium iodide are in a 1:2 molar ratio, 0.04635 mol of lead (II) nitrate will completely react with the following moles of potassium nitrate:
[tex]0.04635molPb(NO_3)_2*\frac{2molKI}{1molPb(NO_3)_2} =0.0927molKI[/tex]
But we only have 0.07885 moles, for that reason KI is the limiting reactant, so we compute the yielded grams of lead (II) iodide, whose molar mass is 461.01 g/mol, by using their 2:1 molar ratio:
[tex]m_{PbI_2}=0.07885molKI*\frac{1molPbI_2}{2molKI} *\frac{461.01gPbI_2}{1molPbI_2} \\\\m_{PbI_2}=18.2gPbI_2[/tex]
Best regards.
When you add a controlled amount of substance known as an impurity to a pure semiconductor, its conductivity increases. This process is known as doping. The addition of an impurity can increase or decrease the number of available electrons. If the number of electrons is increased, the extra electrons conduct electricity. If the number of electrons is decreased, a vacant hole is created. The adjacent electron enters the vacant hole and conducts electricity. Thus, it seems like the holes act as charge carriers. They are considered to be positive charge carriers. Depending upon the charge carriers that conduct electricity, there are two types of semiconductors: p-type semiconductors and n-type semiconductors.Which of the following statements are correct with respect to semiconductors?
a) The addition of group 3A elements to group 4A semiconductors decreases the conductivity of the group 4A semiconductors.
b) The conductivity of semiconductors can be increased by the doping process.
c) As the temperature increases, the conductivity of semiconductors decreases.
d) The addition of group 5A elements to group 4A semiconductors increases the conductivity of the group 4A semiconductors.
e) Holes are charge carriers in p-type semiconductors.
f) Electrons are charge carriers in n-type semiconductors.
Answer:
See explaination
Explanation:
1. The addition of group 3A elements to group 4A semiconductors decreases the conductivity of the group 4A semiconductors: Wrong
The addition of 3A group elements inreases the conductivity and make them extrinsic semiconductors( p-type)
2. The conductivity of semiconductors can be increased by the doping process.: Correct
3.As the temperature increases, the conductivity of semiconductors decreases.. wrong
As the temperature increases, the conductivity of semiconductors increases.
4. The addition of group 5A elements to group 4A semiconductors increases the conductivity of the group 4A semiconductors: Correct : They will create n-type semicoductor.
5.Holes are charge carriers in p-type semiconductors: Correct
6. Electrons are charge carriers in n-type semiconductors: Correct
g A chemistry student needs of thiophene for an experiment. She has available of a w/w solution of thiophene in benzene. Calculate the mass of solution the student should use. If there's not enough solution, press the "No solution" button. Round your answer to significant digits.
The given question is not complete, the complete question is:
A chemistry student needs 5.00 g of thiophene for an experiment. She has available 0.50 kg of a 28.7% w/w solution of thiophene in benzene, Calculate the mass of solution the student should use. If there's not enough solution, press the "No solution" button Be sure your answer has the correct number of significant digits. X
Answer:
The correct answer is 17.4 grams.
Explanation:
As mentioned in the given question, 28.7 percent w/w solution thiophene in benzene shows that,
(wt. of thiophene / wt. of thiopene + benzene) * 100 = 28.7
0.50 kg of the solution indicates that it is 500 grams of the solution.
Therefore, the amount of thiophene found in the 500 grams of the solution is,
500 g * 28.7 / 100 = 143.5 gm
Thus, 143.5 grams of thiophene is found 500 grams of the solution.
Now, 1 gram of thiophene will be in 500/143.5 of solution.
Therefore, 5 grams of thiophene will be in 500/143.5 * 5 g of the solution = 17.42 grams of the solution.
Hence, the mass of the solution to be used by the student in the given case will be 17.4 grams.
What is the molarity of sodium hydroxide solution made by combining 2.0 L of 0.60
NaOH With 495 mL 3.0 M NaOH? Assume the volumes of the two solutions to be additive___M
Answer:
[tex]M=1.1M[/tex]
Explanation:
Hello,
In this case, since we are mixing two NaOH solutions, the first step is to compute the total moles once the mixing is done, by using the volumes and concentrations of each solutions and subsequently adding them:
[tex]n_T=2.0L*0.60\frac{mol}{L}+495mL*\frac{1L}{1000mL}*3.0\frac{mol}{L}= 2.7molNaOH[/tex]
Next, we compute the total volume by adding the volume of each solution:
[tex]V_T=2.0L+495mL*\frac{1L}{1000mL}= 2.495L[/tex]
Finally, we compute the molarity of the resulting solution by the division between the total moles and the total volume:
[tex]M=\frac{2.7mol}{2.495L}\\ \\M=1.1M[/tex]
Best regards.
What is the symbol for the entity that has 17 protons, 20 neutrons, and 18 electrons?
hEy!!!
Chlorine(CL) is the symbol for the entity that has 17 protons,20 neutrons and 18 electrons.
Hope it will be helpful to you...
Answer:chlorine
Explanation:
Which metal is most easily oxidized?
A) Cu B) Ag C) Mg D) Co
Answer:
It is Magnesium because magnesium is the most active out of those three
Explanation:
The metal which is most easily oxidized is : ( C ) Magnesium ( Mg )
What is Oxidization ?
Oxidization involves the process of the addition of oxygen and the removal of electrons from a compound when Magnesium reacts with oxygen it easily gets oxidized when compared to other metals in the question since magnesium is the most active.
Hence we can conclude that The metal which is most easily oxidized is : ( C ) Magnesium ( Mg ).
Learn more about oxidization :https://brainly.com/question/8990767
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A 125 g sample of strontium was heated from 0°C to 20°C. It absorbed 750 J of energy. What is the specific heat capacity of iron?
Answer:
Specific heat capacity of iron (C) = 0.3 J/GK
Explanation:
Given:
Mass of sample (m) = 125 gram
Change in heat (ΔT) = 20°C - 0°C = 20°C
Absorbed energy (ΔE) = 750 J
Find:
Specific heat capacity of iron (C) = ?
Computation:
⇒ Specific heat capacity of iron (C) = ΔE / [mΔT]
⇒ Specific heat capacity of iron (C) = 750 / [125 × 20]
⇒ Specific heat capacity of iron (C) = 750 / [2,500]
⇒ Specific heat capacity of iron (C) = 0.3 J/GK
Answer:
Specific heat capacity of iron (C) [tex]= 0.3[/tex] J/g°C
Explanation:
As we know that
Specific heat capacity of iron (C) [tex]=\frac{\delta E}{ [m* \delta T]}[/tex]
Where [tex]\delta E[/tex] represents the change in the energy
m represents the mass of the sample and
[tex]\delta T[/tex] represents the change in temperature.
Given:
Mass of sample (m) [tex]= 125[/tex] gram
Change in heat ([tex]\delta T[/tex] ) [tex]20 - 0 = 20[/tex]
Absorbed energy ([tex]\delta E[/tex])[tex]= 750[/tex] J
Substituting the given values in above equation, we get -
Specific heat capacity of iron (C)
[tex]= \frac{750}{125*20}[/tex]
Specific heat capacity of iron (C) [tex]= 0.3[/tex] J/g°C
Indicate which molecules demonstrate the correct bonding for carbon atoms. Check all that apply.
CH4
CH3CH4CH2
CH3CH2CH2CH3
CH2CH2CH4
The correct answer is:
CH4
CH3CH2CH2CH3
Answer:
CH4 and CH3 CH2 CH2 CH3
Explanation:
Answer:
CH4 and CH3CH2CH2CH3
Explanation:
its right on edg
SCIENCE QUESTION:
The picture below shows a satellite image of Earth from outer space.What is labeled “White” on the satellite image of Earth?
A. gas in Earth's atmosphere, which keeps Earth's temperature moderate, cycles fluids, and prevents most objects from impacting Earth's surface
B. gravity, which holds all living organisms to Earth, pulls water from clouds, and keeps Earth circulating around the Sun
C. a magnetic field, which controls the movement of water in Earth's water cycle
D. atmospheric ice crystals, which never melt and keep Earth's temperature coo
Answer:
C
Explanation:
The reflection if sunlight on the water makes the water look silver,gray,white
The roles of hydrochloric acid (HCl) in the digestive system?
Answer:
There are several roles of HCl in the digestive system. Some of them are as follows:
There is HCl present in the gastric juice of your stomach, otherwise known as stomach acid. The acidic nature of the HCl in the stomach acid make it useful for quickly breaking down food.HCl's acidic nature also allows it to kill bacteria and other pathogens that you may have ingested, keeping you safe from their dangerous effects.HCl can also contribute Hydrogen ions, which helps to activate pepsinogen, a substance secreted by the stomach wall. The activated pepsinogen is then converted into pepsin, which aids in the digestion of proteins. Because of this, HCl essentially keeps the systems of protein digestion in check. Too much or too little of it can be dangerous.HCl also makes sure that vitamins are properly absorbed and acts as a communicator to other organs in the digestive system.Use the graph to determine which is greater, the heat of fusion or the heat of vaporization. Explain how you used the graph to determine that.
(The substance is water)
Answer:
mdjnibfziedosnninjd.zjcssksskskbsksbivfdlvdxkvfuwhiwhwonsk jsbudwuvsaeigdOhgrauvdslnzarm cxwmvakbxsabxwrifwzpgsdoh
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Claims • Evidence • Reasoning Make
a claim about ways people can stay safe
during storms with high wind and heavy
rains. Summarize evidence to support the
claim and explain your reasoning.
Answer:
the claim is that when people avoid storms they hide in any secret place in there house
Explanation:
when people do that they don't even have to worry about a single thing that will happen to them
Which picture shows how the moon from earth when it’s in the position
Explanation:
This picture shows how the moon from earth when it is in position
