Of the following transitions in the Bohr hydrogen atom, which of the following
results in the emission of the lowest-energy photon.
n = 1 ® n= 6
n=5 ® n=1
n = 6® n=1
n=3® n=5
n=1 ® n=5
What is the frequency of a wave that has a wavelength of 28 m? c = λυ where c = 2.998 x 108 m/s
a. 1.07 x 107 Hz
b. 2.3 x 107 Hz
c. 10 Hz
d. 10.7 Hz
Answer:
The frequency of a wave that has a wavelength of 28 m is 1.07*10⁷ Hz.
Explanation:
Wavelength is the minimum distance between two successive points on the wave that are in the same state of vibration. It is expressed in units of length (m).
Frequency is the number of vibrations that occur in a unit of time. Its unit is s⁻¹ or hertz (Hz).
The propagation speed is the speed with which the wave propagates in the medium, that is, it is the magnitude that measures the speed at which the wave's disturbance propagates along its displacement. Relate the wavelength (λ) and the frequency (f) inversely proportional using the following equation:
v = f * λ.
Being:
v= 2.998*10⁸ m/sf= ?λ= 28 mReplacing:
2.998*10⁸ m/s= f* 28 m
Solving:
[tex]f=\frac{2.998*10^{8}m/s }{28m}[/tex]
f= 1.07*10⁷ Hz
The frequency of a wave that has a wavelength of 28 m is 1.07*10⁷ Hz.
What element has 9 electrons, and 11 neutrons?
fluorineelement has 9 electrons, and 11 neutrons
An empirical research method in which data are gathered from observations of phenomena, hypothesis are formulated and tested, and conclusions are drawn that validate or modify the original hypothesis is known as the: Group of answer choices Gotham theory Scientific Method Niels-Bohr hypothesis Entropy theory
Answer:
Scientific Method
Explanation:
Science is empirical in nature. The entire purpose of science is to discover new knowledge.
The empirical research method in science all begins with gathering observations from phenomena. After that, the researcher formulates appropriate hypothesis which are rigorously tested.
The conclusions drawn from testing the original hypothesis validate or modify the original hypothesis.
I need answers to question 1,2,3
Answer:
1. 0.125 mole
2. 42.5 g
3. 0.61 mole
Explanation:
1. Determination of the number of mole of NaOH.
Mass of NaOH = 5 g
Molar mass of NaOH = 23 + 16 + 1
= 40 g/mol
Mole of NaOH =?
Mole = mass /molar mass
Mole of NaOH = 5/40
Mole NaOH = 0.125 mole
2. Determination of the mass of NH₃.
Mole of NH₃ = 2.5 moles
Molar mass of NH₃ = 14 + (3×1)
= 14 + 3
= 17 g/mol
Mass of NH₃ =?
Mass = mole × molar mass
Mass of NH₃ = 2.5 × 17
Mass of NH₃ = 42.5 g
3. Determination of the number of mole of Ca(NO₃)₂.
Mass of Ca(NO₃)₂ = 100 g
Molar mass of Ca(NO₃)₂ = 40 + 2[14 + (3×16)]
= 40 + 2[14 + 48]
= 40 + 2[62]
= 40 + 124
= 164 g/mol
Mole of Ca(NO₃)₂ =?
Mole = mass /molar mass
Mole of Ca(NO₃)₂ = 100 / 164
Mole of Ca(NO₃)₂ = 0.61 mole
Explain how carbon’s bonding ability makes it unique.
[tex]\huge\fcolorbox{red}{pink}{Answer ♥}[/tex]
The carbon atom is unique among elements in its tendency to form extensive networks of covalent bonds not only with other elements but also with itself. ... Moreover, of all the elements in the second row, carbon has the maximum number of outer shell electrons (four) capable of forming covalent bonds.
Hope it helps uh ✌️✌️✌️
Gud mrng
What are the effects of acid precipitation in city centers
Answer:
Answer to the following question is as follows.
Explanation:
Acid rain causes harm to houses and buildings by dissolving stone or corroding metal exposed to the elements. Acid rain can degrade calcium carbonate or calcium-based chemicals found in some of these products.
The acidic particles damage metal and accelerate the deterioration of paint and stone. They also make buildings and other structures, like as monuments, filthy.
3) The spectrum of the unknown mixture is a mixture of two substances among the five. What are these two substances
Answer:
a. H + d. Na
Explanation:
This is Mixture of H and Na. Because of H and in the emission and Absorption spectrum of H Total 5 lines [Red, Green, Blue and Purple (2)) are present and in the spectrum of Na Two yellow lines are present. In the mixture all this lines are are also 5 + Present. Total lines are 5+2= 7 (H+ Na)
Therefore, the answer is a. H + d. Na
what are the six chemicals in production of liquid soaps
1. Sodium triphosphate ·
2. Sodium hydroxide ·
3. potassium hydroxide
4. Sodium Lauryl Sulfate · 5.Hydroxyethylcellulose ·
6. Sodium carbonate
How many liters of hydrogen can be produced at a pressure of 2 atm and a temperature of 298 K?
Answer: A volume of 1.16 L hydrogen is produced at a pressure of 2 atm and a temperature of 298 K.
Explanation:
Given: Mass of Mg = 2.3 g
Pressure = 2 atm
Temperature = 298 K
The reaction equation is as follows.
[tex]Mg + 2HCl \rightarrow MgCl_{2} + H_{2}[/tex]
This shows that 1 mole of Mg gives 1 mole of [tex]H_{2}[/tex].
Hence, moles of Mg for the given mass is calculated as follows.
[tex]Moles = \frac{mass}{molar mass}\\= \frac{2.3 g}{24.30 g/mol}\\= 0.095 mol[/tex]
Hence, 0.095 moles of Mg will give 0.095 moles of [tex]H_{2}[/tex].
Formula used to calculate volume is as follows.
PV = nRT
where,
P = pressure
V = volume
n = no. of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into the above formula as follows.
[tex]PV = nRT\\2 atm \times V = 0.095 mol \times 0.0821 L atm/mol K \times 298 K\\V = \frac{0.095 mol \times 0.0821 L atm/mol K \times 298 K}{2 atm}\\= 1.16 L[/tex]
Thus, we can conclude that a volume of 1.16 L hydrogen is produced at a pressure of 2 atm and a temperature of 298 K.
need help w the questions in the pic! thankyouu
Answer: Here are the answers
Explanation:
7a) Calcium Chloride +water+carbon dioxide
b)Calcium Oxide +Carbon dioxide
8a) zinc + carbon monoxide
b) Aluminum + Carbon dioxide
c) Lead + carbon dioxide
describe the formation of ionic bonds in potassium chloride compound (5 marks)
Answer:
When the two atoms are in contact, potassium readily transfers its outer electron to chlorine which readily accepts it, resulting in both atoms achieving a state of eight outermost electrons. With this electron transfer, the ionic bond in KCl is formed.
What are the steps for writing the formula for an ionic compound? Naming an ionic compound?
Answer:
i hope it will help you
Explanation:
To find the formula of an ionic compound, first identify the cation and write down its symbol and charge. Then, identify the anion and write down its symbol and charge. Finally, combine the two ions to form an electrically neutral compound.
How many of each kind of atom is in one molecule of water? 1 hydrogen atom and 2 oxygen atoms 1 hydrogen atom and 1 oxygen atom 2 hydrogen atoms and 1 oxygen atom 2 hydrogen atoms and 2 oxygen atoms
Answer:
What period is the atom in?
1.
What group is the atom in?
What is the name of this atom?
What other atom would have similar
properties to the atom?
Will this atom conduct electricity well
Explanation:
How many of each kind of atom is in one molecule of water? 1 hydrogen atom and 2 oxygen atoms 1 hydrogen atom and 1 oxygen atom 2 hydrogen atoms and 1 oxygen atom 2 hydrogen
and 2 oxygen atoms
What is the balance equation for
_AI+_Pb(NO3)2—__Pb+__Ca(NO3)2
Answer:
2 Al + 3 Pb(NO3)2 > 2 Al(NO3)3 + 3 Pb
Explanation:
What is the general function of enzymes in the human body?
O A. They make fatty acids unsaturated.
OB. They speed up chemical reactions.
O C. They store genetic information.
D. They carry instructions for making proteins.
Answer:
C
they store genetic information
B. They speed up chemical reactions
need help asap!!!
so i don’t necessarily need an answer just how to solve everything.
this is the first one:
calcium hydroxide + ammonium chloride
the instructions are attached to this question. i’m just not sure how to do everything. it doesn’t give me the products side only the reactants so how am i supposed to write and balance the equation?
Explanation:
とおふぉくぉをえおろとようおいおぽあおそ・
'」*とまっぉのもヴぉこぉぞぽ、こ、
Answer:
Ca(OH)2 + 2NH4Cl .................. CaCl2 + 2NH3 + 2H2O
In which of the following will the density increase?
Group of answer choices
An iron bar is heated.
A lead weight is moved from sea level to the top of a high mountain.
A sample of water is frozen.
A diamond is submerged in water.
A sample of chlorine gas is compressed.
calculate the final pressure of a gas that is expanded from 725cm³ at 30C and 1.19 atm to 1.12cm³ at 43C
Answer:
Final pressure, P2 = 1088.89 atm
Explanation:
Given the following data;
Initial volume, V1 = 725 cm³Initial temperature, T1 = 30°CInitial pressure, P1 = 1.19 atmFinal volume, V2 = 1.12 cm³Final temperature, T2 = 43°CTo find the final pressure (P2), we would use the combined gas law.
Mathematically, the combined gas law is given by the formula;
[tex] \frac {PV}{T} = k [/tex]
[tex] \frac {P_{1}V_{1}}{T_{1}} = \frac {P_{2}V_{2}}{T_{2}} [/tex]
Substituting into the formula, we have;
[tex] \frac {1.19*715}{30} = \frac {P_{2}*1.12}{43} [/tex]
[tex] \frac {850.85}{30} = \frac {P_{2}*1.12}{43} [/tex]
[tex] 28.3617 = \frac {P_{2}*1.12}{43} [/tex]
Cross-multiplying, we have;
[tex] 28.3617 * 43 = 1.12P_{2} [/tex]
[tex] 1219.5531 = 1.12P_{2} [/tex]
[tex] P_{2} = \frac {1219.5531}{1.12} [/tex]
Final pressure, P2 = 1088.89 atm
Trends in the periodic table indicate that the element with the greatest ionization energy is in which of the following periods and groups?
a
Period 2, Group 1
b
Period 7, Group 2
c
Period 6, Group 17
d
Period 1, Group 18
Answer:
D Period 1, Group 18
Explanation:
it's helium
it's top right corner of the periodic table
Los 4 números cuánticos del oxígeno
Give structural formula of ethylene. What type of bond is found in between carbon and hydrogen? Why is the bond between carbon and carbon weak in it?
Answer:
See explanation
Explanation:
The structure of ethylene is shown in the image attached. The two carbon atoms have a double covalent bond between them.
The two carbon atoms are sp2 hybridized. The bond between them is a covalent bond, there is one pi bond and one sigma bond between the carbon atoms. Between carbon and hydrogen, there are covalent bonds also. The covalent bonds are sigma bonds.
The pi bonds between carbon atoms is weaker than the sigma bonds between the carbon atoms. This is because, the side-by-side overlap the p orbitals in a pi bond is less effective than the end-to-end overlap of a sigma bond.
An atom has9 electrons and 9 protons at the start. If it loses 2 electrons, what would the net charge on the atom be
Answer:
i hope it will help you
Explanation:
there will be 7 electrons and 9 protons will have 2+ charge.
A hot metal plate at 150°C has been placed in air at room temperature. Which event would most likely take place over the next few minutes? Molecules in both the metal and the surrounding air will start moving at lower speeds. Molecules in both the metal and the surrounding air will start moving at higher speeds. The air molecules that are surrounding the metal will slow down, and the molecules in the metal will speed up. The air molecules that are surrounding the metal will speed up, and the molecules in the metal will slow down. Mark this and return
Nung hoàn toàn 173,8g Kali pemanganat để điều chế khí oxi. a/ Tính thể tích khí oxi thu được (đktc). b/ Đốt 12,4g photpho trong lọ chứa khí oxi trên. Sau khi phản ứng kết thúc đưa que đóm còn tàn đỏ vào ống nghiệm thì que đóm có bùng cháy không? Vì sao
Answer:
45
Explanation:
because the number is right
How many ATOMS of boron are present in 3.61 grams of boron trifluoride ?
Hi there!
[tex]\large\boxed{3.203 * 10^{22} atoms}[/tex]
We can use the following conversions to solve:
Total mass --> amount of mols --> amount of atoms (Avogadro's number)
Begin by calculating the amount of boron trifluoride in 3.61 grams:
3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃
Use avogadro's number to convert:
0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms
(Please help)
What is the most common isotope for element X
Answer:
Isotope 2
Explanation:
Isotope 2 is the most abundant. Its percent abundance is 78.68% which is the largest percentage, and therefore the most common of the isotopes presented.
Good luck!
Si se analizan muestras de Al2O3 en diversos laboratorios se encuentra que todas tienen 52,94% de aluminio (Al) y 47,06% de oxígeno (O). Este dato experimental corresponde a lo expresado por la ley de:
A) La ley de las proporciones definidas
B) La ley de las proporciones múltiples
C) La ley de la conservación de la masa
D) La ley de la conservación de la energía
1 x 10^-3 m is the same as which of the following? Select all that apply.
a
10000 m
b
1/1000 m
c
1/0.1 m
d
0.001 m
e
100 m
Answer: b and d
Explanation:
1×10^-3=1×1/10³=1×1/1000=1/1000 so b is correct
1×10^-3=1/1000=0.001
so d is correct
The general shape that an electron is located within an energy level_____
Answer:
Concentric circles
Explanation:
The energy levels are shown as concentric circles around the central nucleus, and the electrons are placed from the inside out. The first two electrons are found in the first energy level, and the third electron is found in the second energy level.
