I am from Nepal i don't know this language
Give the relation of energy (E) and frequency (v) as given by Planck. Calculate the frequency and energy of a photon of radiation having wavelength 3000°A.
Pls answer correctly,need it urgently...
Solution:-1
[tex]\\ \sf\longmapsto E=hv[/tex]
E denotes to Energy h denotes to planks constantv denotes to frequency.Solution:-2
Wavelength=3000Å[tex]\boxed{\sf \lambda=\dfrac{c}{v}}[/tex]
[tex]\\ \sf\longmapsto v=\dfrac{c}{\lambda}[/tex]
[tex]\\ \sf\longmapsto v=\dfrac{3\times 10^8m/s}{3000\times 10^{-10}m}[/tex]
[tex]\\ \sf\longmapsto v=0.001\times 10^{18}s^{-1}[/tex]
[tex]\\ \sf\longmapsto v=1.0\times 10^{15}s^{-1}[/tex]
Now
[tex]\\ \sf\longmapsto E=hv[/tex]
[tex]\\ \sf\longmapsto E=6.626\times 10^{-34}Js\times 1.0\times 10^{15}s^{-1}[/tex]
[tex]\\ \sf\longmapsto E=6.6\times 10^{-19}J[/tex]
Each component in a mixture contributes a fraction to the total number of moles in the mixture. This fraction is called the _____ fraction of the component. In a mixture of gases, this fraction is proportional to the _____ pressure for each gas present.
Answer:
Each component in a mixture contributes a fraction to the total number of moles in the mixture. This fraction is called the _mole_ fraction of the component. In a mixture of gases, this fraction is proportional to the _mole_ pressure for each gas present.
A mixture of reactants and products for the reaction shown below is at
equilibrium in a 2.0 L container. What would most likely happen to the
equilibrium if the volume of the container were increased to 4.0 L?
N.(g) + 3H2(g)
22NH3(g)
Answer:
The system will shift to the left producing more moles of gases trying to maintain the original pressure of the system
Explanation:
Based on LeChatelier's principle, a change in temperature, pressure, volume or concentration on a system result in an opposing change trying to maintain the initial equilibrium conditions.
In the reaction:
N₂(g) + 3H₂(g) ⇄ 2NH₃(g)
4 moles of gas reacts producing 2 moles of gas.
In a gas reaction, the system will try to maintain the total pressure.
If the volume of the container increases, the system will shift to the side of the reaction that has more moles of gases in order to maintain the pressure.
That means if in the reaction the volume of the container increase from 2.0L to 4.0L the system will shift to the left producing more moles of gases trying to maintain the original pressure of the system.
Based on this chart, what percentage of energy comes from fossil fuels?
Sources of Energy
Petroleum
37%
Other
1%
Natural Gas
24%
Renewable
Energy
7%
Coal
23%
Nuclear
Electric Power
8%
O A. 60%
OB. 23%
Ο Ο Ο Ο
C. 84%
O D. 37%
Answer:
37%+24%+23%=84% , i wish my answer is correct
Hi can someone help me with completing the word equation and writing a balanced chemical equation with state symbols
Answer:
Sodium hydroxide + ammonium chloride — Sodium chloride + ammonia gas + water
Explanation:
NaOH + NH4Cl — NaCl + NH3 + H2O
The pOH of a solution is 3.1. Which of the following is true about the solution? (1 point)
It is acidic and has a pH of 10.9.
It is basic and has a pH of 10.9.
It is acidic and has a pH of 6.2.
It is basic and has a pH of 6.2.
Answer:
The answer is option BExplanation:
To solve the question above we must first find the pH of the solution using the formula
pH + pOH = 14
pOH = 3.1
So we have
pH + 3.1 = 14
pH = 14 - 3.1
pH = 10.9
Since it's pH is 10.9 the solution is a basic solution since it's pH lies in the basic region.
Hope this helps you
In a mass spectrometer, the ions are sorted out in which of the following ways?
A. By accelerating them through electric field
B. By accelerating them through magnetic field
C. By accelerating them through electric and magnetic field
D. By applying a high voltage
Answer:
C
Explanation:
The ions are first accelerated electrically, and then bended magnetically to sort them and record them.
A mixture of gasoline and air explodes when it encounters a spark. This is
known as
O A. a synthesis reaction
O O O
B. a precipitation reaction
C. fuel efficiency
o
D. a combustion reaction
SUBMI
Answer:
D. A combustion reaction
Explanation:
True or false. A car engine must have fossil fuels to work
Answer: False
Explanation:
It is not that it must have fossil fuels only because car can also work on hydro power and water. So it should be energy.
must click thanks and mark brainliest
Its fact that a car can also run on water and hydropower means that it does not necessarily need fossil fuels. Therefore, a car engine must have fossil fuels to work is false.
What are fossil fuels ?An extracted and burnt fossil fuel is a hydrocarbon-containing substance that naturally originated in the Earth's crust from the remnants of extinct plants and animals.
Natural gas, crude oil, and coal are the three primary fossil fuels. Fossil fuels are resources that resemble rocks, gases, or liquids that are burnt to produce electricity.
They are employed as energy sources in the electrical and transportation industries and include coal, natural gas, and oil. They are also a major contributor to global warming pollution.
Fossil fuels are used to generate energy, they are burnt to provide heat in homes, electricity in big power plants, and power for engines.
Thus, a car engine must have fossil fuels to work is false.
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Which of the following describes the entropy change as a solution is made
from a liquid and solid?
O A. AS = 0
O B. ASAH
C. AS< 0
D. AS> 0
Answer:
S>O.
Explanation:
Chemical changes can reduced entropy in an open system. When gas turns into a liquid or when a liquid turns into a solid; entropy is reduced. hope this helps you :)
what are the efficient things needed for a village
Answer:
Those aspects which are something a village needs are specified beneath.
Explanation:
Things being equally necessary to make living simpler and therefore more enjoyable. The government has promised to continue providing basic facilities to either an unpopulated location, including such roads, drinkable water, as well as electric power. Therefore, throughout the village, certain things accessible with maximum variety and quality that have become the basic requirements for this human existence.Lab Safety Rule #3 says to always add acids or bases to the solvent and NEVER the other way around true or false?
Answer:
true
Explanation:
The standard laboratory rule is to always add acids or bases to solvent and not the other way round.
The dissolution of concentrated acids/bases in solvents (water) generates heat energy. Thus, if the solvent is added to them, a layer of hot weak acid or base will be formed and this will boil and spray around, causing an explosion.
On the other hand, if acid/base is added to solvents, they flow into the solvents and get diluted immediately without any boiling taking place. Hence, it is safe to add acid/base to solvents and not the other way round.
Please help, this assignment is to hard for me. :(
Answer:
603000 J
Explanation:
The following data were obtained from the question:
Energy required (Q) =...?
Mass (M) = 10000 g
Specific heat capacity (C) = 2.01 J/g°C
Overheating temperature (T2) = 121°C
Working temperature (T1) = 91°C
Change in temperature (ΔT) =.?
Change in temperature (ΔT) =T2 – T1
Change in temperature (ΔT) = 121 – 91
Change in temperature (ΔT) = 30°C
Finally, we shall determine the energe required to overheat the car as follow:
Q = MCΔT
Q = 10000 × 2.01 × 30
Q = 603000 J
Therefore, 603000 J of energy is required to overheat the car.
The element phosporus is located to the right of the element magnesium along the same period in the periodic table.
Ytu perform an electrolysis reaction using FeCl, iron (1) chloride. Which of the following will happen?
A. Chlorine will move to the positive electrode and become reduced.
B. Iron will move to the positive electrode and become oxidized.
C. Chlorine will move to the negative electrode and become oxidized.
D. Iron will move to the negative electrode and become reduced.
Answer:
The answer is "Option B"
Explanation:
when we react with FeCl, iron, and chloride to both the electrolysis. So, iron is charged positive ion, as well as passes to the negative, is cathode electrode. But there is a decrease in the cathode.
The equation can be defined as follows:
[tex]FeCl_2[/tex] [tex]\longrightarrow[/tex][tex]Fe + Cl_2[/tex]
In the above equation, when the iron chloride electrolysis solution, it will give the iron(II) and the chlorine. This process happens when the hydrogen chloride solution at a temperature of about 90 ° C.
Answer: D
Explanation: As Fe is positive charged while chlorine is negative charged.
(D) is correct. As iron moves to negative and it get reduce as negative electrode is cathode
How would removing invasive species from an
ecosystem help reduce the chances of a native
species becoming extinct?
A
The native species would go extinct
sooner.
B
The native species would no longer be
infected by diseases
C
The native species would be better adapt
for survival.
D
The native species would not have to
compete for necessary resources,
The correct answer is D. The native species would not have to compete for necessary resources
Explanation:
Invasive species, which include any living organism that is not native in an ecosystem, contribute to the extinction of native species as they compete for resources such as food, shelter, etc. with native species. For example, the Asian Carp, which was introduced to lakes in the U.S. consumes plankton, which reduces the amount of plankton available for native fish. In this context, by removing invasive species native species would not have to compete for resources and their chances to extinct will fall.
Easyyy plz
What Is the Reactivity Series? ...
Answer:
In chemistry the reactivity series is an empirical, calculated, and structurally analytical progression of a series of metals, arranged by their "reactivity" from highest to the lowest.
Answer:
In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. More reactive metals have a greater tendency to lose electrons and form positive ions.
A reactivity series of metals could include any elements. For example,
A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, zinc, iron, copper, silver, and gold.
A good way to remember the order of a reactivity series of metals is to use the first letter of each one to make up a silly sentence. For example, People Say Little Children Make A Zebra Ill Constantly Sniffing Giraffes.
Observations of the way that these elements react with water, acids, and steam enable us to put them into this series.
The tables show how the elements react with water and dilute acids:
Element Reaction with water
Potassium Violently
Sodium Very quickly
Lithium Quickly
Calcium More slowly
Element Reaction with dilute acids
Calcium Very quickly
Magnesium Quickly
Zinc More slowly
Iron More slowly than zinc
Copper Very slowly
Silver Barely reacts
Gold Does not react
Note that aluminum can be difficult to place in the correct position in the reactivity series during these experiments. This is because its protective aluminum oxide layer makes it appear to be less reactive than it really is. When this layer is removed, the observations are more reliable.
Non-metals in the reactivity series
It is useful to place carbon and hydrogen into the reactivity series because these elements can be used to extract metals.
Here is the reactivity series including carbon and hydrogen:
A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, carbon, zinc, iron, hydrogen, copper, silver, and gold.
Note that zinc and iron can be displaced from their oxides using carbon but not using hydrogen. However, copper can be extracted using carbon or hydrogen. Displacement reactions of metal oxides
A more reactive metal will displace a less reactive metal from a compound. The thermite reaction is a good example of this. It is used to produce white-hot molten (liquid) iron in remote locations for welding. A lot of heat is needed to start the reaction, but then it releases an incredible amount of heat, enough to melt the iron.
aluminium + iron(III) oxide → iron + aluminium oxide
2Al + Fe2O3 → 2Fe + Al2O3
Because aluminum is more reactive than iron, it displaces iron from iron(III) oxide. The aluminum removes oxygen from the iron(III) oxide:
iron is reduced
aluminum is oxidized
Reactions between metals and metal oxides allow us to put a selection of metals into a reactivity series. Using metals A, B, and C:
Metal A Metal B Metal C
A oxide X Displaces A Displaces A
B oxide No reaction X No reaction
C oxide No reaction Displaces C X
Metal A cannot displace either B or C - so it must be the least reactive and be at the bottom of this reactivity series.
Metal B displaces both A and C - so it must be the most reactive and be at the top of this reactivity series.
Metal C displaces A but cannot displace B - so it must be more reactive than A but less reactive than B, and be in between them in this reactivity series.
In general, the greater the difference in reactivity between two metals in a displacement reaction, the greater the amount of energy released.
Aluminum is much higher than iron in the reactivity series, so the thermite reaction releases a lot of energy. Magnesium is very high in the reactivity series, and copper is very low - so the reaction between magnesium and copper oxide is more violent.
Therefore, the order is:
A list of letters from most reactive to least reactive: B, C and A,
Displacement reactions of solutions
A more reactive metal will displace a less reactive metal from a solution of one of its salts. For example:
magnesium + copper(II) sulfate → copper + magnesium sulfate
Mg(s) + CuSO4(aq) → Cu(s) + MgSO4(aq)
In this reaction, the blue color of the copper(II) sulfate fades as it is used up (magnesium sulfate solution is colorless). We would also see copper metal forming.
Reactions between metals and solutions of metal salts allow us to put a selection of metals into a reactivity series. Using metals J, K, and L:
Metal J Metal K Metal L
J sulfate X No reaction No reaction
K sulfate Displaces K X Displaces K
L sulfate Displaces L No reaction X
Metal J displaces both K and L - so it must be the most reactive and be at the top of this reactivity series.
Metal K cannot displace either J or L - so it must be the least reactive and be at the bottom of this reactivity series.
Metal L displaces K but cannot displace J - so it must be more reactive than K but less reactive than J, and be in between them in this reactivity series.
- sorry I'm late and it's is long -_-||
which one of the following has the smallest atomic radius a)Mg2+ b)O2- c)Na+ d)F-
Answer:
Mg2+
Explanation:
o2- =2,8
mg2+ =2,8
na+ =2,8
f- =2,8
since they are all same it depends on protons.
mg2+ has least protons
.hlp me to solve mcq
Answer:
i) b
ii) c
Explanation:
Please see attached picture for full solution.
Use the following steps to balance the redox reaction using half-reactions. Zn(s) + Fe3+ Zn2+ + Fe(s) (unbalanced) a. Write balanced oxidation and reduction half-reactions. Indicate which is the oxidation reaction and which is the reduction reaction. (6 points) b. Balance the charge in the two half-reactions by multiplying the half-reactions by the correct multiplication factors. (4 points) c. Add the equations and simplify to get the balanced equation.
Answer:
Explanation:
a )
Zn = Zn²⁺ + 2e ( oxidation reaction )
Fe³⁺ + 3e = Fe( s ) ( reduction reaction )
b )
[ Zn = Zn²⁺ + 2e ] x 3
[ Fe³⁺ + 3e = Fe( s ) ] x 2
-------------------------------------------------------------------
3 Zn + 2 Fe³⁺ + 6e = 3 Zn²⁺ + 2 Fe ( s ) + 6e
3 Zn + 2 Fe³⁺ = 3 Zn²⁺ + 2 Fe ( s )
Calculate the number of molecules present in 2.50 mol H2S?
A. 1.51 x 10^24 molecules
B. 2.50 x 10^23 molecules
C. 1.5 x 10^23 molecules
One mole of H₂S gas contains 6.022 × 10²³ H₂S molecules. Hence, 2.50 mol of H₂S contains 1.50 × 10²⁴ molecules. Thus, option A is correct.
What is Avogadro number?Any substance containing 6.022 × 10²³ number of atoms is called one mole of that substance. This number is called Avogadro number. Thus, one mole every elements contains Avogadro number of atoms.
Similarly a compound is made of molecules. One mole of a compound contains 6.022 × 10²³ number of molecules. The mass of a compound with Avogadro number of molecules is called its molar mass.
As any other compound, one mole of H₂S contains 6.022 × 10²³ molecules. Therefore, the number of molecules in 2.50 moles of H₂S is :
2.50 moles × 6.022 × 10²³ molecules/mol = 1.50 × 10²⁴molecules
Hence, the number of molecules present in 2.50 moles of H₂S is 1.50 × 10²⁴.
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how many moles of sodium are produced in 46g of substance?
Answer:
Only 2moles are produced from it
Scientific method quick check
Answer:
Quick you said:
-Purpose/Question
Ask a question.
-Research
Conduct background research. Write down your sources so you can cite your references. In the modern era, a lot of your research may be conducted online. Scroll to the bottom of articles to check the references. Even if you can't access the full text of a published article, you can usually view the abstract to see the summary of other experiments. Interview experts on a topic. The more you know about a subject, the easier it will be to conduct your investigation.
-Hypothesis
Propose a hypothesis. This is a sort of educated guess about what you expect. It is a statement used to predict the outcome of an experiment. Usually, a hypothesis is written in terms of cause and effect. Alternatively, it may describe the relationship between two phenomena. One type of hypothesis is the null hypothesis or the no-difference hypothesis. This is an easy type of hypothesis to test because it assumes changing a variable will have no effect on the outcome. In reality, you probably expect a change but rejecting a hypothesis may be more useful than accepting one.
-Experiment
Design and perform an experiment to test your hypothesis. An experiment has an independent and dependent variable. You change or control the independent variable and record the effect it has on the dependent variable. It's important to change only one variable for an experiment rather than try to combine the effects of variables in an experiment. For example, if you want to test the effects of light intensity and fertilizer concentration on the growth rate of a plant, you're really looking at two separate experiments.
-Data/Analysis
Record observations and analyze the meaning of the data. Often, you'll prepare a table or graph of the data. Don't throw out data points you think are bad or that don't support your predictions. Some of the most incredible discoveries in science were made because the data looked wrong! Once you have the data, you may need to perform a mathematical analysis to support or refute your hypothesis.
-Conclusion
Conclude whether to accept or reject your hypothesis. There is no right or wrong outcome to an experiment, so either result is fine. Accepting a hypothesis does not necessarily mean it's correct! Sometimes repeating an experiment may give a different result. In other cases, a hypothesis may predict an outcome, yet you might draw an incorrect conclusion. Communicate your results. The results may be compiled into a lab report or formally submitted as a paper. Whether you accept or reject the hypothesis, you likely learned something about the subject and may wish to revise the original hypothesis or form a new one for a future experiment.
Me podrían ayudar con esta tarea porfa, paso a paso se los agradecería muchísimo. -El sulfuro de hidrógeno se quema con oxígeno para dar dióxido de azufre y agua. ¿Cuántos moles de dióxido de azufre se forman a partir de la reacción de 0.250 moles de 2 y 0.300 moles de 2? 2h2s(g)+3o2(g)→2so2(g)+2h2o(g)
Answer:
0.2 moles de SO₂
Explanation:
La reaccción es:
2H₂S (g) + 3O₂ (g) → 2SO₂ (g) + 2H₂O(g)
Asumimos que tenemos 0.250 moles de sulfuro y 0.3 moles de oxígeno.
En primer lugar tenemos que averiguar el reactivo limitante.
Si 2 moles de sulfuro de hidrógeno reaccionan con 3 moles de oxígeno, según la reacción.
Entonces 0.250 moles, reaccionarían con (0.250 . 3) /2 = 0.375moles
Tenemos entonces 0.3 moles de oxígeno y necesitamos 0.375 (no nos alcanza). Por lo tanto el O₂ es el limitante y ahora podemos calcular el producto formado. La ecuación nos dice:
3 moles de oxígeno pueden producir dos moles de SO₂
Entonces 0.3 moles (que son los que tenemos) de O₂ producirían:
(0.3 . 2) /3 = 0.2 moles de SO₂
Think of a real life simple problem and apply scientific method to solve the problem given to the guide questions.
Scientific Approach is to identify a problem and finding solution to the problem. There are various steps in scientific approach to solve a problem,
Identify the problem
Analyze the impact
Find available solution
Evaluate different alternative solutions
Choose the best alternative
Apply the solution to the problem
Measure the results
Lets say there is a fire at some place.
There are various solution available, the fire can be slowed down by water, using fire extinguisher or sand.
The best alternative is to use fire extinguisher.
The fire is vanished after the use of fire extinguisher.
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if any 1 studying 11th can u plz send me the chemistry notes for chapter 2 STRUCTURE OF AN ATOM lesson
plz send me honestly cause i have exam day after tommorow .so plz send unwanted answer
I BEG U
Answer:
What
You cant just send notes you also have to say where you are and which book you are using because others are different
Which of the following isotopes would deflect the most in a mass spectrometer?
a) Sr-84
b) Sr-86
c) Sr-87
d) Sr-88
The correct answer is Sr-84. The lightest specie is the most deflected while the heaviest specie is the least deflected.
In mass spectroscopy, chemical substances can be identified by looking at their respective mass-to-charge ratios of gaseous ions in electric and magnetic fields. The is achieved using a mass spectrometer.
The lightest specie undergoes the greatest deflection while the heaviest specie undergoes the heaviest deflection accordingly in a mass spectrometer.
In this case, Sr-84, is the lightest specie hence it should be the least deflected specie.
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6. What type of bond is called covalent bond?
Answer:
ECovalent bond, in chemistry, the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons. ... Silicon, carbon, germanium, and a few other elements form covalently bonded solids.
Please make me Brain liest );
What does the VSEPR theory describe
Answer:
The shape of a molecule based on the number of electron pairs on the valence shell of its central atom
Explanation:
The improvement of the Sidgwick-Powell theory came to be known as the Valence Shell Electron Pair Repulsion theory (VSEPR). This theory approaches the determination of molecular shape from the perspective of the number of electron pairs on the valence shell of the central atom in the molecule.
Electron pairs on the valence shells of atoms leads to repulsion. Repulsion between two lone pairs is greater than repulsion between a lone pair and a bond pair which is also greater than repulsion between two bond pairs.
Lone pairs cause more repulsion, hence they distort molecules from the ideal shape predicted based on their electron domain geometry.
Consider the reaction of 2.5 grams of Li (s) reacting with 0.5 grams of N2 (g) to produce Li3N (s). A) How many total grams of Li3 N (s) would be produced? B) Which of the starting elements is the limiting reagent, and how many grams of the non-limiting reagent remain after the reaction has completed?
Answer:
A) The amount in grams of Li₃N produced is 1.243 g
B) N₂, is the limiting reagent
The mass of the non-limiting reagent, Li, remaining after the reaction is completed is 1.757 g
Explanation:
The given parameters are;
The mass of Li(s) = 2.5 grams
The mass of N₂ (g) = 0.5 grams
The chemical equation for the reaction can be presented as follows;
6 Li (s) + N₂ (g) → 2 Li₃N
Therefore, 6 moles of Li reacts with 1 mole of N₂ to produce 2 moles of Li₃N
The molar mass of Li = 6.941 g/mol
The molar mass of N₂ = 28.0134 g/mol
The number of moles of a reactant or product, n is given by the relation;
n = Mass of substance/(Molar mass of the substance)
For lithium, Li, n = 2.5/6.941 = 0.3602 moles
For Nitrogen gas, N₂, n = 0.5/28.0134 = 0.01785 moles
A) Given that 1 mole of N₂ to produces 2 moles of Li₃N
0.01785 moles of N₂ will produces 2×0.01785 = 0.0357 moles of Li₃N
The molar mass of Li₃N = 34.83 g/mol
The mass of Li₃N = 34.83 g/mol × 0.0357 moles = 1.243 g
B) 6 moles of Li reacts with 1 mole of N₂ to produce 2 moles of Li₃N
0.3602 moles will reacts with 1/6×0.3602 = 0.06003 mole of N₂
Therefore, N₂, is the limiting reagent and we have;
0.01785 moles of N₂ will react with 6×0.01785 = 0.1071 moles of Li
The number of of moles of Li left = 0.3602 - 0.1071 =0.2531 moles
The mass of lithium left = 0.2531 moles × 6.941 g/mol = 1.757 g
The mass of lithium remaining after the reaction is completed = 1.757 g.