What is the work function of gold metal in kJ/mol if light with λ = 234 nm is necessary to eject electrons?
Answer
512kj/mole
Explanation:
What is the work function of gold metal in kJ/mol if light with λ = 234 nm is necessary to eject electrons?
The energy can be calculated using below expresion;
E = hc/λ
Where h= planks constant= 6.626 x 10^-34
c= speed of light= 3 x 10^
λ= wavelength
hc= (6.626 x 10^-34 x 3 x 10^ 8)
=
The temperature of a sample of CH4 gas (10.34 g) in a 50.0 L vessel at 1.33 atm is ________ °C.
a.
984
b.
-195
c.
-1260
d.
-195
Answer:
option C is correct
Explanation:
Considering the ideal gas law and the definition of Avogadro's Number, the correct option is option a. The temperature of a sample of CH₄ gas (10.34 g) in a 50.0 L vessel at 1.33 atm is 984 °C.
In first place, you have to know that ideal gases are a simplification of real gases that is done to study them more easily.
It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.
An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T).
The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P×V = n×R×T
In this case, being the molar mass of CH₄ being 16 [tex]\frac{g}{mole}[/tex], that is, the mass present in one mole of an element or compound, the number of moles that 10.34 grams contains is calculated as:
[tex]10.34 g*\frac{1 mole}{16.04 g} = 0.645 moles[/tex]
So, you know:
P= 1.33 atmV= 50 Ln= 0.645 molesR=0.082 (atm×L)/ (mol×K)T= ?Replacing:
1.33 atm × 50 L= 0.645 moles× 0.082 (atm×L)/ (mol×K) ×T
Solving:
T= [1.33 atm × 50 L] ÷ [0.645 moles× 0.082 (atm×L)/ (mol×K) ]
T≅ 1257 K
Being 273 K equivalent to 0 C, then:
T= 1257 K= 984 C
In summary, the correct option is option a. The temperature of a sample of CH₄ gas (10.34 g) in a 50.0 L vessel at 1.33 atm is 984 °C.
Learn more about the ideal gas law: brainly.com/question/4147359?referrer=searchResults
Each of the two different solids A and B melts at 133 o C. A sample of an unknown solid melts around 133 o C, and is either A or B. How will you determine the identity of the unknown solid
Answer:
See explanation
Explanation:
The melting point range of a pure compound is about 1-2ºC of the expected melting point. An impure solid melts within a range that is both larger than that of the pure substance (>1ºC) and begin at a lower temperature because impurities decrease the meting point. A melting range of 5º or more indicates that a compound is impure.
Since the melting points of A and B are estimated at 133 o C, the melting point range for each pure substance must be slightly different from each other. The melting point of the unknown is measured and its range is compared with the melting point ranges of pure A and B then decision can now be made about the identity of the unknown solid.
How many more electrons are there in the last energy level of phosphorus, atomic
number 15, than there are in the last principal energy level of neon, atomic number 10?
sorry but I need some three point so that's why I didn't
What two options are homogeneous mixture
Answer:
vinegar and soap
Explanation:
Answer:
vinegar and soap
Explanation: just took the test
1. Change the following into correct scientific notation.
a) 0.03050 =
b) 0.256 x 10°=
c) 25.005 10 =
Answer:
a) 0.03050 = 3.050 × 10-²
b) 0.256 x 10°= 2.56 × 10-¹
c) 25.005 10 = 2.500510 × 10¹
Explanation:
Scientific notations is a way of making very large or very small numbers more comprehensive or simplified. It involves the use of power of ten (10^). The numbers are represented to the power of ten. The following format is used:
a x 10^b
where; a is a number or decimal number between 1 and 10 i.e less than 10 but greater than 1
b is the power of ten
To write a number in scientific notation,
- we move the decimal point right or left depending on whether we're trying to reduce or increase the number
- we count the number of times the decimal point was moved. This serves as the b in the format above.
For example,
a) 0.03050 = 3.050 × 10-²
The decimal point was moved rightward twice. This caused the ^-2 power.
b) 0.256 x 10°= 2.56 × 10-¹
The decimal point was moved rightward once. This caused the ^-1 power.
c) 25.005 10 = 2.500510 × 10¹
The decimal point was moved leftward once. This caused the ^1 power.
Using the equations
2 C₆H₆ (l) + 15 O₂ (g) → 12 CO₂ (g) + 6 H₂O (g)∆H° = -6271 kJ/mol
2 H₂ (g) + O₂ (g) → 2 H₂O (g) ∆H° = -483.6 kJ/mol
C (s) + O₂ (g) → CO₂ (g) ∆H° = -393.5 kJ/mol
Determine the enthalpy (in kJ/mol) for the reaction
6 C (s) + 3 H₂ (g) → C₆H₆ (l).
The enthalpy : 49.1 kJ/mol
Further explanationThe change in enthalpy in the formation of 1 mole of the elements is called enthalpy of formation
The enthalpy of formation measured in standard conditions (25 ° C, 1 atm) is called the standard enthalpy of formation (ΔHf °)
Based on the principle of Hess's Law, the change in enthalpy of a reaction will be the same even though it is through several stages or ways
Reaction
1. 2C₆H₆ (l) + 15 O₂ (g) → 12 CO₂ (g) + 6 H₂O (g)∆H° = -6271 kJ/mol
Reverse
12 CO₂ (g) + 6 H₂O (g) ⇒ 2C₆H₆ (l) + 15 O₂ (g) ∆H° = 6271 kJ/mol : 2
6CO₂ (g) + 3H₂O (g) ⇒ C₆H₆ (l) + 15/2 O₂ (g) ∆H° = 3135.5 kJ/mol
2. 2 H₂ (g) + O₂ (g) → 2 H₂O (g) ∆H° = -483.6 kJ/mol x 3/2
3H₂ (g) + 3/2O₂ (g) → 3H₂O (g) ∆H° = -725.4 kJ/mol
3. C (s) + O₂ (g) → CO₂ (g) ∆H° = -393.5 kJ/mol x 6
6C (s) + 6O₂ (g) → 6CO₂ (g) ∆H° = -2361 k/j/mol
-------------------------------------------------------------------------------------
6 C (s) + 3 H₂ (g) → C₆H₆ (l) ∆H° = 49.1 kJ/mol
We add up and the same compound that is on different sides we eliminate
Select the best answer from the choice below. When the wavelength decreases, the frequency:
Answer:
Increases
Explanation:
Frequency and wavelength of lights are inversely proportional to each other.
The wave of light having highest frequency have shortest wavelength and the light with the shortest frequency having highest wavelength.
Formula:
Speed of light = wavelength × frequency
c = λ × f
λ = c/f
This formula shows that both are inversely related to each other.
The speed of light is 3×10⁸ m/s
Frequency is taken in Hz.
It is the number of oscillations, wave of light make in one second.
Wavelength is designated as "λ" and it is the measured in meter. It is the distance between the two crust of two trough.
How would you synthesize 1-hexanol starting from 1-propanol, incorporating a Grignard reagent in the synthesis?
Answer:
hjhjhjhhhhh
Explanation:
What is the concentration of chloride ions in a solution that contains 0.375 g of aluminum chloride in 15.0 mL of solution?
Answer:
0.561 M
Explanation:
Step 1: Given data
Mass of aluminum chloride (m): 0.375 gMolar mass of aluminum chloride (M): 133.34 g/molVolume of the solution (V): 15.0 mLStep 2: Calculate the molar concentration of aluminum chloride (C)
We will use the following expression.
[tex]C = \frac{m}{M \times V(L) } = \frac{0.375g}{133.34 g/mol \times 0.0150L } = 0.187M[/tex]
Step 3: Write the reaction of dissociation of aluminum chloride
AlCl₃(aq) ⇒ Al³⁺(aq) + 3 Cl⁻(aq)
Step 4: Calculate the concentration of chloride ions
The molar ratio of AlCl₃ to Cl⁻ is 1:3. The concentration of Cl⁻ is 3/1 × 0.187 M = 0.561 M
How many electrons does Sodium lose to become an ion
Using the two models, compare the processes of nuclear fusion and nuclear fission. What do the two processes have in common?
Choose all that apply.
A)
Energy is released.
B)
Elements are created
0)
A chain reaction occurs.
D)
Besides energy, neutrons are released.
E)
Both processes begin with an unstable nucleus.
Answer:it’s A and B
Explanation:
Answer:
A and B
Explanation:
They’re both fusion.
What was the test or tests that made you decide if you compound was an aldehyde or a ketone and why?
Answer:
Tollen's test or silver mirror test is use to distinguish between ketone and aldehyde.
Explanation:
Tollen's test is use to distinguish aldehyde from ketone because Tollen reagent consist of silver nitrate and ammonia and it oxidized aldehydes to carboxylic acid and the silver Ag+ is reduced to solid silver Ag. It form a inner film wall on the tube that look like mirror. Ketone do not react with Tollen reagent and therefore does not form silver mirror on the tube wall.
A student combines a sample of gas (2.0 L) at 3.5 atm with with another gas (1.5 L) at 2.8 atm pressure into an empty 7.0 L flask. Assuming the gases are combined at constant temperature, what is the total gas pressure (in atmospheres) in the 7.0 L flask?
Answer:
Total gas pressure is 1.60 atm
Explanation:
To solve this question we can use the Ideal Gases Law. We need to determine how many moles of each gas will be finally present at the flask of 7 L.
Let's asume the gas, are at Asbsolute T°, 273K
P. V = n . R . T
3.5 atm . 2L = n . 0.082 . 273K
(3.5 atm . 2L) / (0.082 . 273K) = 0.313 moles
(2.8 atm . 1.5L) / (0.082 . 273K) = 0.188 moles
Total moles = 0.313 mol + 0.188 mol = 0.501 mol
Let's calcualte the hole pressure
P . 7L = 0.501 moles . 0.082 . 273K
P = (0.501 moles . 0.082 . 273K) / 7L → 1.60 atm
A 1,500 kg truck is towed sideways out of a mud-hole with a force of 15,000 N. What acceleration of the tow truck is needed to move this vehicle?
Other than the starting material, 2-methylcyclohexanol, what base or bases are present in the dehydration reaction mixture to participate in proton transfers?
a) H2PO4- only
b) H2O and H2PO4-
c) H2O and HSO4-
d) H2O only
Answer:
c) H2O and HSO4-
Explanation:
The dehydration of 2-methylcyclohexanol occurs in the presence of H2SO4. Recall that acids are proton donors in solution; the equilibrium shown below is then set up,
H2SO4(aq) + H2O(l) ⇄H3O^+(aq) + HSO4^-(aq)
The species H2O and HSO4- are two proton acceptors in the system. According to the Brownstead- Lowry definition, a base is a proton acceptor in solution.
Hence H2O and HSO4- are bases present in the dehydration of 2-methylcyclohexanol.
A weather balloon with a volume of 3.40774 L
is released from Earth’s surface at sea level.
What volume will the balloon occupy at an
altitude of 20.0 km, where the air pressure is
10 kPa?
Answer in units of L.
Answer: The volume at an altitude of 20.0 km is 34.5289 L
Explanation:
Boyle's Law: This law states that pressure is inversely proportional to the volume of the gas at constant temperature and number of moles.
[tex]P\propto \frac{1}{V}[/tex] (At constant temperature and number of moles)
[tex]P_1V_1=P_2V_2[/tex]
where,
[tex]P_1[/tex] = initial pressure of gas = 101.325 kPa ( at sea level)
[tex]P_2[/tex] = final pressure of gas = 10 kPa
[tex]V_1[/tex] = initial volume of gas = 3.40774 L
[tex]V_2[/tex] = final volume of gas = ?
Now put all the given values in the above equation, we get the final volume of gas.
[tex]101.325\times 3.40774=10\times V_2[/tex]
[tex]V_2=34.5289L[/tex]
Thus the volume at an altitude of 20.0 km is 34.5289 L
Therefore, the final pressure of the gas will be 3.75 atm
For at least the last century Florida has experienced a hurricane season every year, from June to November. Which of the following describes this occurrence the BEST?
A. Florida's precipitation
B. Florida's global pattern
C. Florida's climate
D. Florida's weather
Answer:
Florida's Global Pattern.
Explanation:
Because of where Florida sits, the weather in the Gulf of Mexico actually blows enough water to Create tidal waves, and also hurricanes. at least that's what I was told cause I live here :>
Potassium hydroxide has the chemical formula KOH. It feels slippery and is used in cleaning liquids. Based on this description, potassium hydroxide is most likely a(n) A acid. B base. с neutral solution. D pH indicator.
Answer:
it should be a base
Explanation:
this is because solutions such as bleach are usually slippery on the hands, and mostly bases are in cleaning solutions
Which of the following has a nonpolar bond? *
02
HCI
NH3
CH4
Answer: CH4
Explanation:
BRAINLESS PLEASE
Answer:
O₂
Explanation:
The example of the compound or the molecule that forms a non-polar bond is oxygen gas.
Oxygen gas has a formula of O₂
Since this is a homonuclear molecule, the two bonding atoms have the same kind of electronegativity. The difference is therefore zero. In such a molecule, there is equal sharing of the electron pair between the atoms and no electrostatic charge on the molecule.what is the molecular geometry of c atom in ch3nh2
Answer:
compound is sp3.
Explanation:
Chemistry of Life Practice Active 8 1 What type of organic compound is used for building cell parts?
Answer:
Carbohydrates
Explanation:
What happens when this match is struck against the side of the match box?
Answer:
It lights on fire
Explanation:
The friction sparks the match causing it to go on fire.
i really need help with the rest of this assignment. theres 10 pages of multiple choice questions, i can mark brainliest and pay money if you help me :)
Answer:
Hey! I'll help you.
Explanation:
I got your back.
How would one use a Grignard-based synthesis to accomplish the following transformation? benzyl bromide (PhCH2Br) to 3-phenyl-1-propanol 1. Mg, Et20 2. ethylene oxide3. H3O+ 1. Mg, Et2O 2. Ethanol3. H3O+ 1. Mg, Et202. Ethylene 3. H3O+ None of the above.
Answer: ghfbg
Explanation: fgfghfg
Which elements-O2, Rb, Sb, Pt, Y, Sm, Mn, Rh, Sn, Li-will react (a) with a solution of I to generate I2; (b) with a solution of Ag' to generate Ag; and (c) with a solution of Nat to generate Na?
Answer:
a) O2, Pt, Rh
b) Rb, Y, Sm, Mn, Sn, Li
c)Rb
Explanation:
We must consider the reduction potentials of each of the species in the question.
In (a) above, all the elements whose reduction potential is higher than the redox potential for the oxidation of I^- will react with a solution of I^- to generate I2 as shown above.
In (b) above, all the strong reducing agents can donate electrons to Ag^+ and reduce it to Ag as shown above.
In (c) Rb has a more negative reduction potential than sodium hence it can react with a solution of sodium salt to generate sodium metal.
What does this image represent?
Amine group
Carbonyl group
Ether group
Hydroxyl group
Answer:
ether group
Explanation: I looked it up
In frequency modulation, which wave property remains constant?
Answer:
The correct answer is - Amplitude.
Explanation:
Frequency modulation is a method or procedure that sends or transmits the signals such as radio broadcasting, telecommunication where the value of the transmitted signal is provided by the frequency of a high-frequency wave that carries the signal.
In this method of encoding the information, the amplitude of the carrier remains the same or constant but frequency varies in accordance with the modulating signal.
Answer:
The answer is C Amplitude
Explanation:
Because you can give me Brainiest PLZZZZZZZZZZZZZZZZZZZZ
Balance chemical equation hbr(aq)+o2(g) h20+br2
Answer:
2HBr + O2 = H20 +Br2
Explanation:
Answer:
4hbr(aq) + O2(g) = 2H2O + 2Br2
Explanation:
Use the image to complete the sentences.
At left a grid labeled A of regularly arranged orange balls with small movement lines near each. At right a grid labeled B of regularly arranged orange balls with large movement lines near each.
Two different substances, Substance A and Substance B, are in direct contact with each other and are at different temperatures.
The particles in Substance B are vibrating
the particles in Substance A. This means Substance B is
Substance A and conduction will
.
Answer:
1. FASTER THAN- #2
2. WARMER THAN #1
3. OCCUR FROM SUBSTANCE B TO SUBSTANCE A- #3
Explanation:
I did the assignment On edg And got it right
Answer:
Use the image to complete the sentences.
At left a grid labeled A of regularly arranged orange balls with small movement lines near each. At right a grid labeled B of regularly arranged orange balls with large movement lines near each.
Two different substances, Substance A and Substance B, are in direct contact with each other and are at different temperatures.
The particles in Substance B are vibrating
✔ faster than
the particles in Substance A. This means Substance B is
✔ warmer than
Substance A and conduction will
✔ occur from Substance B to Substance A
.
Explanation:
I know im late