Answer:
8.59
⋅
10
17
Explanation:
You can start by figuring out the energy of a single photon of wavelength
505 nm
=
505
⋅
10
−
9
m
.
To do that, use the equation
E
=
h
⋅
c
λ
Here
h
is Planck's constant, equal to
6.626
⋅
10
−
34
.
J s
c
is the speed of light in a vacuum, usually given as
3
⋅
10
8
.
m s
−
1
λ
is the wavelength of the photon, expressed in meters
Plug in your value to find--notice that the wavelength of the photon must be expressed in meters in order for it to work here.
E
=
6.626
⋅
10
−
34
J
s
⋅
3
⋅
10
8
m
s
−
1
505
⋅
10
−
9
m
E
=
3.936
⋅
10
−
19
J
So, you know that one photon of this wavelength has an energy of
3.936
⋅
10
−
19
J
and that your laser pulse produces a total of
0.338 J
of energy, so all that you need to do now is to find how many photons are needed to get the energy output given to you.
0.338
J
⋅
1 photon
3.936
⋅
10
−
19
J
=
8.59
⋅
10
17
photons
−−−−−−−−−−−−−−−−−
The answer is rounded to three sig figs.
an ion has 38 protons, 36 electrons, qnd 40 neutrons, what is its mass #?
Answer:
Strontium - 38 (atomic #)
Explanation:
An ion with 38 protons, 36 electrons, and 40 electrons is Strontium. Strontium's atomic number is 38.
At STP, which gaseous sample has the same number
of molecules as 5.0 liters of O2 (g)?
A) 6.0 L of F2 (g)
C) 3.0 L of H2 (g)
B) 4.5 L of O2 (g)
D) 5.0 L of Cl2 (g)
What is the main concern for environmental scientists?
Answer:
Global Warming
Explanation:
The biggest concern for environmental scientists is Global Warming. Our Earth is getting warmer which is having drastic effects on our planet. Such effects include increased natural fires, decreased water supply, decreased farm yields, increased floodings, etc. Global Warming poses a huge threat to humanity and it is because of humanity's constant and ever growing usage of fossil fuels that Global Warming is becoming such a threat. This is what environmental scientists are mainly focused on.
Can you look at the picture Look at the picture ASAP and help please?
Answer:
Volume of the reaction vessel is increased - shift to the left
The reaction is cooled down - shift to the right
H2 is added to the system - shift to the right
The pressure of the system is decreased - shift to the left
A catalyst is added to the system - no change
Water is removed from the system - shift to the right
Explanation:
When a constraint such as a change in temperature, pressure or volume is imposed on a reaction system in equilibrium, the equilibrium position will shift in such a way as to annul the constraint.
When the volume of a reaction system is increased, the equilibrium position shifts in the direction in which there is the highest total volume. This is the left hand side.
Since the reaction is exothermic (heat is given out) when the reaction is cooled down, the forward reaction is favoured.
Adding of reactants shifts the equilibrium position to the right hand side hence when H2 is added, the equilibrium position shifts to the right.
Decreasing the pressure shifts the equilibrium position to the direction of higher total volume hence the equilibrium shifts to the left when pressure is decreased.
A catalyst has no effect on the equilibrium position. It increases the rate of forward and reverse reaction to the same extent hence the equilibrium position is unaffected.
Removal of water from the system increases the rate of forward reaction since a product is being removed from the reaction system.
HELP ME PLZ AND THANKS I WILL MARK YOU AS BRAINLIEST!!!
Answer:
Final pressure = 6 atm
Final volume = 1.1 L
Final temperature = 100 K
Explanation:
We are given;
Initial Pressure; P1 = 2 atm
Initial volume; V1 = 3.3 L
Initial temperature; T1 = 27° C + 273 = 300 K
Final pressure; P2 = 6 atm
We will use Boyles law to get the final volume.
P1V1 = P2V2
V2 = (P1 × V1)/P2
P2 = (2 × 3.3)/6
V2 = 1.1 L
We can use Charles law to find the final temperature.
V1/T1 = V2/T2
T2 = (V2 × T1)/V1
T2 = (1.1 × 300)/3.3
T2 = 100 K
A heater in a classroom provides heat, but the temperature in the room stays the same why
Guys I don't know science, if you are intelligent tell me what is science
Explanation:
Science is the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on evidence
Which chemical equation represents a process that takes place in yeast cells? O A. CO2 + H20 + light energy - O2 + sugar O B. O2 + sugar CO2 + H2O + ATP energy C. 02 + sugar CO2 + H2O + light energy O D. CO2 + H20 + ATP energy - 02 + sugar SUBMIT
Answer:
A
Explanation:
In plant and yeast cells pyruvate is converted into carbon dioxide and a type of alcohol called ethanol . This process is called fermentation and yields only two molecules of ATP per glucose molecule broken down.
[tex]CO_2 + H_20[/tex]+ light energy → [tex]O_2[/tex] + sugar chemical equation represents a process that takes place in yeast cells. Hence, option A is correct.
What are chemical equations?A representation of a chemical reaction using symbols of the elements to indicate the amount of substance, usually in moles, of each reactant and product.
In plant and yeast cells pyruvate is converted into carbon dioxide and a type of alcohol called ethanol. This process is called fermentation and yields only two molecules of ATP per glucose molecule broken down.
Hence, option A is correct.
Learn more about chemical equations here:
https://brainly.com/question/12363199
#SPJ2
Can someone please help with these 2?
Equilibrium shifts to the right.
OPTION A
What is the molar solubility of MgF2 in a 0.36 M Mg(NO3)2 solution? For MgF2, Ksp = 8.4 × 10^–8
Answer:
2.4 × 10⁻⁴ M
Explanation:
Step 1: Calculate the concentration of Mg²⁺ coming from Mg(NO₃)₂
Mg(NO₃)₂ is a strong electrolyte and the molar ratio of Mg(NO₃)₂ to Mg²⁺ is 1:1. The initial molar concentration of Mg²⁺ is 1/1 × 0.36 M = 0.36 M.
Step 2: Make an ICE chart for the solution of MgF₂
MgF₂(s) ⇄ Mg²⁺(aq) + 2 F⁻(aq)
I 0.36 0
C +S +2S
E 0.36+S 2S
The solubility product constant is:
Ksp = [Mg²⁺] × [F⁻]² = (0.36+S) × (2S)²
Since S <<< 0.36, 0.36+S ≈ 0.36.
Ksp = 0.36 × 4S² = 8.4 × 10⁻⁸
S = 2.4 × 10⁻⁴ M
Bret and Cindy took different routes to travel from Point A to Point E. Bret took the route along A, B, C, D, and E. Cindy took the route along A, F, and E and reached the destination in 2 hours. Their routes are shown.
If Bret's average speed was twice Cindy's average speed, what was Bret's average speed?
3 miles per hour
6 miles per hour
8 miles per hour
9 miles per hour
Why can light be treated like a particle?
Answer:
Light can be treated like particles because it is made of chunks like things called protons.
g 1.000 atm of oxygen gas, placed in a container having a pinhole opening in its side, leaks from the container 2.14 times faster than does 1.000 atm of an unknown gas placed in this same apparatus. Which of these species could be the unknown gas
The question is incomplete, the complete question is;
1.000 atm of Oxygen gas, placed in a container having apinhole opening in its side. leaks from the container 2.14 timesfaster thatn 1.000 atm of an unknown gas placed in this sameapparatus. Which of the following species could be theunknown gas?
A. CL2
B. SF6
C. Kr
D. UF6
E. Xe
Answer:
SF6
Explanation:
From Graham's law;
Let the rate of diffusion of oxygen be R1
Let the rate of diffusion of unknown base be R2
Let the molar mass of oxygen by M1
Let the molar mass of unknown gas be M2
Hence;
R1/R2 = √M2/M1
So;
2.14/1 = √M2/32
(2.14/1)^2 = M/32
M= (2.14/1)^2 × 32
M= 146.6
This is the molar mass of SF6 hence the answer above.
when the sum 4.9965 + 2.11 + 3.887 is calculated, to how many decimal places should the answer be reported?
Answer:
the correct answer is four decimal places
List the safety measures she should take to stay safe while she carries out her experiment
Answer:
Wearing gloves
Explanation:
it helps on not touching chemicals
the beaker contains 0.2556 m h2so3 and the buret contains 0.3106 m naoh what happens to the conductivity during titration
Answer:
Before the equivalence point, conductivity is decreasing. After the equivalence point, conductivity is increasing
Explanation:
In solution H2SO3 produce H+ ions and SO3²⁻ ions. In the same way, NaOH produce Na⁺ and OH⁻ ions. The conductivity of a solution is directly proportional to the concentration of ions in a solution. During titration, you are adding more NaOH (That is, more Na⁺ and OH⁻ ions). But each moles of OH⁻ reacts with H⁺ ion producing H₂O. That means the moles of Na⁺ that you are adding = Moles of H⁺ are been consumed. The concentration of ions remains approximately constant. But, H⁺ ion conducts better than Na⁺ ion. That means before the equivalence point, conductivity is decreasing. But after the equivalence point you will add OH- ions in excess increasing ion concentration increasing the conductivity:
After equivalence point, conductivity is increasing.
Según la cinética química para que una reacción ocurra, los átomos o moléculas deben
I. Chocar con la suficiente energía. II. Chocar con una concentración adecuada. III. Ser choques efectivos
A) Solo I.
B) Solo I y II.
C) Solo I y III.
D) Solo II y III.
E) I, II, III.
Answer:
solo I
Explanation:
Según esta teoría para que se produzca una reacción deben cumplirse tres condiciones: Las moléculas de los reactivos tienen que chocar entre sí. Estos choques deben de producirse con energía suficiente de forma que se puedan romper y formar enlaces químicos.
how do sea breezes and land breezes affect local weather
+
c)
FeCl3 +
NH4OH
Fe(OH)3
NHACI
The question is incomplete, the complete question is:
Write the net ionic equation for the below chemical reaction:
(c): [tex]FeCl_3+3NH_4OH\rightarrow Fe(OH)_3+3NH_4CI[/tex]
Answer: The net ionic equation is [tex]Fe^{3+}(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)[/tex]
Explanation:
Net ionic equation is defined as the equations in which spectator ions are not included.
Spectator ions are the ones that are present equally on the reactant and product sides. They do not participate in the reaction.
(c):
The balanced molecular equation is:
[tex]FeCl_3(aq)+3NH_4OH(aq)\rightarrow Fe(OH)_3(s)+3NH_4Cl(aq)[/tex]
The complete ionic equation follows:
[tex]Fe^{3+}(aq)+3Cl^-(aq)+3NH_4^+(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)+3NH_4^+(aq)+3Cl^-(aq)[/tex]
As ammonium and chloride ions are present on both sides of the reaction. Thus, they are considered spectator ions.
The net ionic equation follows:
[tex]Fe^{3+}(aq)+3OH^{-}(aq)\rightarrow Fe(OH)_3(s)[/tex]
Use the observations about each chemical reaction in the table below to decide the sign (positive or negative) of the reaction enthalpy AH and reaction entropy
AS.
Note: if you have not been given enough information to decide a sign, select the "unknown" option.
Answer:
Use the observations about each chemical reaction in the table below to decide the sign (positive or negative) of the reaction enthalpy AH and reaction entropy AS. Note: if you have not been given enough information to decide a sign, select the "unknown" option observations conclusions reaction ΔΗ is (pick one) The reverse of this reaction is always spontaneous. A As is (pick one) This reaction is spontaneous except below ΔΗ is (pick one) 38. °C but proceeds at a faster rate above (pick one) 91. °C As is ΔΗ iS (pick one) Crystallization of a pure compound is C spontaneous only below 146. °C. AS is (pick one) X
The earth's crust is:
made of rock
the thinnest layer
broken into large pieces called plates
all of the above
Answer:
all of the above
Explanation:
have a nice day :-)
Note: Please show all work and calculation setups to get full credit. T. he following may be used on this assignment: specific heat of (water=4.184 J/g oC; ice=2.03 J/g oC; steam=1.99 184 J/g oC); heat of fusion of water=80. cal/g; heat of vaporization=540 cal/g; 1cal=4.184J.
Calculate the energy required (in J) to convert 25 g of ice at -15 oC to water at 75 oC.
Answer:
16974J of energy are required
Explanation:
The energy required is:
* The energy to heat solid water from -15°C to 0°C using:
q = m*S*ΔT
* The energy to convert the solid water to liquid water:
q = dH*m
* The energy required to increase the temperature of liquid water from 0°C to 75°C
q = m*S*ΔT
The first energy is:
q = m*S*ΔT
m = Mass water = 25g
S is specific heat of ice = 2.03J/g°C
ΔT is change in temperature = 0°C - (-15°C) = 15°C
q = 25g*2.03J/g°C*15°C
q = 761.3J
The second energy is:
q = dH*m
m = Mass water = 25g
dH is heat of fusion of water = 80cal/g
q = 80cal/g*25g
q = 2000cal * (4.184J/1cal) = 8368J
The third energy is:
q = m*S*ΔT
m = Mass water = 25g
S is specific heat of water= 4.184J/g°C
ΔT is change in temperature = 75°C-0°C = 75°C
q = 25g*4.184J/g°C*75°C
q = 7845J
The energy is: 7845J + 8368J + 761J =
16974J of energy are required
Complete the following equations (note that the equations are not balanced). Use the act
necessary
03
Li > K> Ba > Sr> Ca > Na > Mg > Al > Mn > Zn > Cr> Fe > Cd >
Co > Ni > Sn > Pb > H > Sb> Bi > Cu > Ag > Pd > Hg > Pt > Au
K1+Pb(NO3)2 →?
O KNO3 + Pbl2
O KNO3 + Pbl
OKNI + PbO2
Answer:
Explanation:
a
State three natural conditions under which plasmolysis could occur
Answer:
When the cell is placed in salt solutionWhen leave celss dryWhen cells are placed in sugar solutionExplanation:
Hope this helps
Homologous chromosomes pair up during prophase I to form a ________________.
Fill it in PLSSSSSSSSSSSSS
i will give brainlist
2.31 grams of KNO3 are dissolved in 4.15 g of H2O. What is the concentration of the solution in units of gKNO3/100gH2O?
Answer: The concentration of the solution is 55.66g[tex]KNO_3[/tex]/100g[tex]H_2O[/tex]
Explanation:
A solution consists of solute and solvent. A solute is defined as the component present in a smaller proportion while the solvent is defined as the component that is present in a larger proportion.
We are given:
Mass of [tex]KNO_3[/tex] = 2.31 g
Mass of water = 4.15 g
To calculate the concentration in g[tex]KNO_3[/tex]/100 g [tex]H_2O[/tex], we apply unitary method:
In 4.15 g of water, the mass of [tex]KNO_3[/tex] present is 2.31 g
So, in 100 g of water, the mass of [tex]KNO_3[/tex] present will be [tex]\frac{2.31}{4.15}\times 100=55.66g[/tex]
Hence, the concentration of the solution is 55.66g[tex]KNO_3[/tex]/100g[tex]H_2O[/tex]
A sample of 10K gold contains the following: 10.0g gold, 4.0g silver, 5.0g copper, and 5.0g nickel. What is the percent gold in the sample?
Answer:
I don't no answer sorry
Explanation:
you follow me
What is the molar mass of 12?
Answer:
I assume your talking about carbon when you say 12 so it'd be 12 grams if you are
Explanation:
The molar mass of any substance in grams per mole is numerically equal to the mass of that substance expressed in atomic mass units.
Hope this helps you some
the most correct definition of a chemical bond is the:
Use the following balanced equation to perform the requested operations.
2Li + CuSO3 → Cu + Li2SO3
When 3.33 moles of lithium are consumed, how many moles of Li2SO3 are produced?
How many moles of copper are produced when 12.33 grams of CuSO3 are reacted?
Explanation:
U can use molar ratio of
Li : Li2SO3
2 : 1
so 3.33÷2=1.665 so 1.67 moles
then u can use the
moles = mass ÷ mr
= 12.33÷ 100.08
= 0.123 moles of CuSO3 then use the molar ratio
CuSO3 : Cu
1:1
so 0.123 moles of cu
hope this make sense:)