Answer:
Wavelength (λ) = 1.875 × 10⁻⁶ m
Explanation:
Given:
Energy (e) = 1.06 × 10⁻¹⁹ J
Find:
Wavelength (λ) = ?
Computation:
e = hc / λ
λ = hc / e
where c = 3 × 10⁸
Planck's constant (h) = 6.625 × 10⁻³⁴
So,
Wavelength (λ) = (6.625 × 10⁻³⁴)(3 × 10⁸) / (1.06 × 10⁻¹⁹)
1. Wavelength (λ) = 1.875 × 10⁻⁶ m
2. Given n = 4 to n = 3 both are integer not fraction so, electron is quantize
What combination of substances will give a buffered solution that has a pH of 5.05? (Assume each pair of substances is dissolved in 5.0 L of water.) (Kb for NH3 = 1.8 ´ 10–5; Kb for C5H5N = 1.7 ´ 10–9) Select one: a. 1.0 mole NH3 and 1.5 mole NH4Cl b. 1.5 mole NH3 and 1.0 mole NH4Cl c. 1.0 mole C5H5N and 1.5 mole C5H5NHCl d. 1.5 mole C5H5N and 1.0 mole C5H5NHCl e. none of these
Answer:
c. 1.0 mole C5H5N and 1.5 mole C5H5NHCl
Explanation:
We can determine pH of a buffer using H-H equation:
pH = pKa + log [A⁻] / [HA]
Where [A⁻] is concentration of conjugate base and [HA] concentration of weak acid. These concentrations can be computed as moles of each species.
We need to determine pKa of both NH₃ and C₅H₅N buffers, thus:
pKb = -log Kb
NH₃ pKb = -log 1.8x10⁻⁵ = 4.74
C₅H₅N pKb = -log 1.7x10⁻⁹ = 8.77
And pKa = 14 - pKb:
NH₃ pKa = 14 - 4.74 = 9.26
C₅H₅N pKb = 14 - 8.77 = 5.23
A buffer works only under pH's between pKa-1 and pKa + 1. As pKa NH₃ buffer is 9.23 is not possible to produce a buffer with pH 5.05 for this system.
Thus, we only will compute the buffers made with C₅H₅N:
c. 1.0 mole C5H5N (Weak base) and 1.5 mole C5H5NHCl (Conjugate acid)
pH = pKa + log [A⁻] / [HA]
pH = 5.23+ log [1.0 moles] / 1.5 moles]
pH = 5.05d. 1.5 mole C5H5N and 1.0 mole C5H5NHCl
pH = pKa + log [A⁻] / [HA]
pH = 5.23+ log [1.5 moles] / 1.0 moles]
pH = 5.41Right solution is:
c. 1.0 mole C5H5N and 1.5 mole C5H5NHClIf a sample of aluminum with a density of 2.70 g/cm^3 displaces 36.0 mL of water when placed in a beaker, what is its mass?
13.3 g
97.2 g
0.075 g
Answer:
The answer is 97.2g .
Explanation:
Given that 1 mL is equals to 1 cm². Then we have to apply Density formula :
[tex]density = \frac{mass}{volume} [/tex]
[tex]let \: density = 2.7 \: , \: volume = 36[/tex]
[tex]2.7 = \frac{mass}{36} [/tex]
[tex]mass = 2.7 \times 36[/tex]
[tex]mass = 97.2 \: grams[/tex]
explain all the 4 quantum numbers in detail
[tex]HELLO![/tex]
To completely describe an electron in an atom, four quantum numbers are needed:
Energy (n).Angular momentum (ℓ).Magnetic moment (mℓ).Spin (ms).[tex]MiraculousAlejandra[/tex].
I need help with b) c) and what is the electronic configuration of atom E
Answer:
(b) A and C belongs to same group.
(c) D is a non metal.
Explanation:
The Electronic Configuration of E is
[tex]1s {}^{2} 2s {}^{2}2p {}^{6} 3s {}^{2} 3p {}^{6} 4s {}^{2} [/tex]
The recommended dose of aminophylline for children is 1.0 mg/kg/hr. 15 mL of a 30 mg/mL sltn is added to a 150 mL bottle of D5W. At what rate mL/hr should the injection be delivered to 35 lb child
Answer:
The answer is "6.68 [tex]\frac{ml} {hr}[/tex]".
Explanation:
It's going to be 18.18 kg to turn body mass to kg.
Size 1mg / kg / hr, therefore = 1 x 18.18
= 18.18 kg / hr
now we adding 30 mg / ml of dextrose = 30 x 15
[tex]=\frac{450mg}{15 ml +150 ml}[/tex]
of dextrose, from 15 ml to 150 ml;
Therefore, now 450 mg in 165m:
[tex]= \frac{ 450}{165}\\ \\=2.72 \frac{mg} {ml}[/tex]
now divide the 18.18 by 2.72:
[tex]=\frac{18.18}{2.72}[/tex]
= 6.68 [tex]\frac{ml} {hr}[/tex]
Hỗn hợp E gồm hai este đơn chức X và Y (MX< MY). Thủy phân hoàn toàn 0,11 mol E cần vừa đủ
120 ml dung dịch NaOH 1M, chưng cất dung dịch sau phản ứng, thu được ancol propylic và 8,78 gam hỗn
hợp Z gồm ba muối. Phần trăm khối lượng của Y trong E là
Answer:
write in English bro? can you?
Explanation:
I can't understand your language sorry .
1. The Tyndall Effect is most useful for distinguishing between: *
a solute and a solvent
O a suspension and a solution
a colloid and a suspension
a colloid and a solution
Answer:
a colloid and a solution
Explanation:
When solute particles completely dissolve in a solvent, a true solution is formed. The solute particles in this case are so little that they can not be seen with naked eyes. A true solution does not scatter rays of light.
In a false solution, the solute particles are larger than the solute particles in true solutions but are not large enough to be seen with naked eyes. False solutions scatter rays of light. False solutions are also called colloids.
The major difference between a solution and a colloid is that colloids scatter light rays (Tyndall effect) while a true solution does not scatter light rays.
Convert 48,987 minutes to years
using the method of dimensional analysis
Answer:
Explanation:
48000 minutes [ 1 hour / 60 min ] 1 day / 24 hours ] [365 days / year]
48000 * [ 1/(60 * 24 * 365)]
48000 * [1 / 525600]
There are 0.0930954years in 48000 minutes
Match each step of the scientific method with its matching example.
Match Term Definition
A) The growth of green algae is recorded every day for several weeks and compared
B) The data recorded in the experiment supports the hypothesis about how algae reproduce.
C) Based on what other scientists have done, algae life cycles are affected by light.
D) Under the same temperature and water conditions, green algae is grown under natural light, blue light, and green light.
Experiment
Conclusion
Research
Analysis
Answer: I did the quiz and got it correct
Explanation:
Biosphere- B
Ecosystem- C
Biome- D
Habitat- A
Scientific Method
What is Scientific Method
A method or procedure that consists of systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
Experiment- The growth of green algae is recorded every day for several weeks and compared
Conclusion- Under the same temperature and water conditions, green algae is grown under natural light, blue light, and green light.
Research-Based on what other scientists have done, algae life cycles are affected by light.
Analysis- The data recorded in the experiment supports the hypothesis about how algae reproduce.
For more information visit
https://brainly.com/question/497944
Which statement correctly describes the relationship between thermal energy and particle movement?
1 As thermal energy increases, particle movement does not change.
2 As thermal energy increases, it is not possible to predict particle movement.
3 As thermal energy increases, there is less particle movement.
4 As thermal energy increases, there is more particle movement.
The correct statement that describes the relationship between thermal energy and particle movement is "As thermal energy increases, there is more particle movement".
WHAT IS THERMAL ENERGY?
Thermal energy is the energy that emanates from heat or change in temperature. Thermal energy is directly proportional to the movement of particles. This means that an increase in thermal energy depicts an increase in the kinetic energy (energy due to motion) of the particles involved.Hence, as thermal energy of substance increases, there is more particle movement of that substance.
Learn more: https://brainly.com/question/24291347
Susan said, "if I fertilize my geranium plants, they will blossom"
Choose the correct step in the scientific method
A. recognize a problem
B. from hypothesis
C. test the hypothesis with an experiment
D. draw conclusions
Answer:
This is called a hypothesis, which can be identified by the if... then... format.
So, the correct option is B. Form a hypothesis.
Let me know if this helps!
Answer:
C
Explanation:
cho 6,5 g Zn tác dụng với dung dịch chứa 12g HCl. Thể tích khí H2 ( ở đktc ) là
Answer: nHCl = 12/36,5= 0,38(mol)
nZn = 6,5/65 = 0,1(mol)
Ta có pt: Zn + 2HCl --> ZnCl2 + H2
Vì 2n Zn = 0,2 < n HCl = 0,38 nên HCl dư
Theo PTHH :
n H2 = n Zn = 0,1(mol)
V H2 = 0,1.22,4 = 2,24(lít)
Explanation:
how will you measure the length of a curved line by using a thread?
What is the atomic number of copper
Answer:
29
Explanation:
Copper is a chemical element with the symbol Cu and atomic number is 29
Explanation:
convert 0.5 seconds to milliseconds and .02 km to meters
Answer:
0,5 seconds = 500 millisecondes
2 km = 200 meters
Explanation:
If oxygen causes fire to burn, why didn't the world explode when fire burns at a particular place...since oxygen is everywhere...? Explain...
Answer:
Oxygen does not burn. It is not flammable, but it is an oxidizer.
Explanation
I think you are misunderstanding what is meant by "fire burns up air". Fire does use oxygen when it burns. But it also produces carbon dioxide. An oxygen molecule has two oxygen atoms in it. Fires use this to produce carbon dioxide by adding a single carbon atom from the fire’s fuel (wood, for instance).
hope it'll help:)
What element is depicted by the following electron configuration:
you can determine this by
adding the numbers of the sub-shells, 2+2+6+2+4=16the number on the last sub-shell, 4 means on the 4th main groupthe 3 before 3p4, tells us on the 3rd period, so the answer is Sulphur.calculate the weight of 3.491 into 10 to the power 19 molecules of cl2
Answer:
The mass of 3.491 × 10¹⁹ molecules of Cl₂ of Cl₂ is 4.11 × 10⁻³ grams
Explanation:
The number of particles in one mole of a substance id=s given by the Avogadro's number which is approximately 6.023 × 10²³ particles
Therefore, we have;
One mole of Cl₂ gas, which is a compound, contains 6.023 × 10²³ individual molecules of Cl₂
3.491 × 10¹⁹ molecules of Cl₂ is equivalent to (3.491 × 10¹⁹)/(6.023 × 10²³) = 5.796 × 10⁻⁵ moles of Cl₂
The mass of one mole of Cl₂ = 70.906 g/mol
The mass of 5.796 × 10⁻⁵ moles of Cl₂ = 70.906 × 5.796 × 10^(-5) = 4.11 × 10⁻³ grams
Therefore;
The mass of 3.491 × 10¹⁹ molecules of Cl₂ of Cl₂ = 4.11 × 10⁻³ grams.
In the image above the ruler is measuring in centimeters. The blue cylinder falls somewhere between 2.7cm and 2.8cm according to the ruler. Since we can estimate the last digit I would say that the length of the cylinder is 2.76cm. Since I am estimating any number 2.72cm or 2.78cm could also be correct.
Why would 2.755 not be a correct measurement according to estimating the last digit?
Answer:
The accuracy of the measuring ruler is given as tenth of a centimetre and given that the image above the ruler is measuring in between a tenth of a centimetre, it is therefore measuring at a higher accuracy than the ruler
The least count of the vernier scale = (Main scale's smallest reading)/(Number of vernier scale divisions)
Where;
Main scale's smallest reading = 0.1 cm
Number of vernier scale divisions = 10
We have;
The least count of the vernier scale =0.1/10 = 0.01
The image above the ruler, (the vernier scale measurement) should therefore measure at hundredth of a centimetre and the value of the measurement given to two places of decimal, 2.XX, as such 2.755 which is of a level of accuracy of a thousandth for the vernier scale would not be correct.
Explanation:
A mixture of liquids having almost the same boiling point cannot be separated by simple distillation?Why?
Answer:
Distillation:
Distillation is the process in which two or more liquids are separated on the basis of their boiling points.
Process:
Liquid mixture is heated. The liquid which is of low boiling point evaporates first and is condensed separately. This is followed by the liquid having more boiling point than the previous one and so on.
Reason:
A mixture of liquids having almost same boiling points cannot be separated. This is because both the liquids will evaporate at almost the same time when heated and thus, we will obtain the same liquid mixture again. No separation will occur.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Peace!What are the problems of turbid water for aquatic plants?
Answer:
Turbidity affects the growth rate of algae (micro-aquatic plants) and other aquatic plants in streams and lakes because increased turbidity causes a decrease in the amount of light for photosynthesis. Turbidity can also increase water temperature because suspended particles absorb more heat.High levels of turbidity can affect aquatic life in several ways.
Too much turbidity might make it difficult for plants to complete photosynthesis, which in turn affects the amount of dissolved oxygen.Fish cannot see well in turbid water making finding food difficult.High turbidity reduces the penetration of sunlight into water and can limit photosynthesis and hence the growth of aquatic plants.Explanation:
Turbidity is the measure of relative clarity of a liquid. The higher the intensity of scattered light, the higher the turbidity. Material that causes water to be turbid include clay, silt, very tiny inorganic and organic matter, algae, dissolved colored organic compounds, and plankton and other microscopic organisms
How many significant figures
are in this number?
107.051
Answer:
there are 6 significant figures in 107.051
Answer:
There Are 6 Significant Numbers
Explanation: But some problems stop at the . so it could 3 if im right but go with 6!
The world is made up of
Answer:
Explanation:
The world is made up of living beings .
One to two paragraphs describing the water cycle
Answer:
The water cycle or hydrologic is a continuous cycle where water evaporates, travels into the air and becomes part of a cloud, falls down to earth as precipitation, and then evaporates again. This repeats again and again in a never-ending cycle. Water keeps moving and changing from a solid to a liquid to a gas, over and over again.
Precipitation creates runoff that travels over the ground surface and helps to fill lakes and rivers. It also percolates or moves downward through openings in the soil to replenish aquifers under the ground. Some places receive more precipitation than others do. These areas are usually close to oceans or large bodies of water that allow more water to evaporate and form clouds. Other areas receive less precipitation. Often these areas are far from water or near mountains. As clouds move up and over mountains, the water vapor condenses to form precipitation and freezes. Snow falls on the peaks.
The continual movement of water on, above, and below the Earth's surface is referred to as the water cycle, also known as the hydrological cycle.
What is water cycle ?The water cycle demonstrates how water is constantly moving both inside the Earth and in the atmosphere. It is a complicated system with a wide range of processes.
Water vapor is created when liquid water evaporates, and this water vapor then condenses to form clouds and falls back to earth as rain and snow.
The constant flow of water between the ground and the atmosphere is known as the water cycle. Water travels to land as precipitation, like snow and rain.
The cycle is then completed by the water evaporating, condensing into clouds in the atmosphere, and precipitating once more on earth. The water cycle is composed mostly of four processes: evaporation, convection, precipitation, and collection.
Thus, The continual movement of water on, above, and below the Earth's surface is referred to as the water cycle.
To learn more about the water cycle, follow the link;
https://brainly.com/question/1151425
#SPJ2
tion 1/3
A white rhinoceros weighs about 1,500 pounds (lb). How many tons (T) does the rhinoceros weigh? (1 T =
A. 1.5 T
o
B. 1 T
C. 0.75 T
D. 0.5 T
Answer:
.75 Tons
Explanation:
1 Ton is equal to 2,000 pounds
According to Dalton, the pressure of a mix of gases in a single container is the sum of all of the pressures of the individual gases: Ptotal = Pa + Pb + … If a 20.0L container at 30°C has 3.4 atm of methane and 1.68 atm of ethane, what is the total pressure of the container?
Answer:
The correct answer is 5.08 atm
Explanation:
This question tests our knowledge of the Dalton's law of partial pressures which is stated in the question; that the pressure of a mixture of non-reacting gases in a single container is the sum of all the pressures of the individual gases.
It can hence be represented mathematically as Ptotal = Pa + Pb + ...
Ptotal = pressure of methane + pressure of ethane
Ptotal = 3.4 atm + 1.68 atm
Ptotal = 5.08 atm
Using d = m/V, what is the (V)olume of a solid that has a density is 14g/cm² and has a
mass of 7 grams.
Answer:
0.5cm²
Explanation:
the volume is found by dividing the mass over the density
v=m/d
=7g/14g/cm²
=0.5cm²
i hope this helps
Answer:
[tex]\boxed {\boxed {\sf 0.5 \ or \ \frac {1}{2} \ cm^3}}[/tex]
Explanation:
We are asked to find the volume of a solid given the density and mass. The formula for density is:
[tex]d= \frac {m}{v}[/tex]
We know the solid's density is 14 grams per cubic centimeter and the mass is 7 grams.
d= 14 g/cm³m= 7 gSubstitute the known values into the formula.
[tex]14 g/cm^3 = \frac{7 \ g}{v}[/tex]
We are solving for the volume of the solid, so we must isolate the variable v. First, cross multiply. Multiply the first numerator by the second denominator, then the first denominator and second numerator.
[tex]\frac {14 g/cm^3}{1} = \frac{7 \ g}{v}[/tex]
[tex]14 \ g/cm^3 * v= 7 \ g * 1[/tex]
[tex]14 \ g/cm^3 * v= 7 \ g[/tex]
Now the variable is being multiplied by 14 grams per cubic centimeters. The inverse operation of multiplication is division, so we divide both sides by 14 g/cm³.
[tex]\frac {14 \ g/cm^3 * v}{14 \ g/cm^3}= \frac {7 \ g }{14 \ g/cm^3}[/tex]
[tex]v= \frac {7 \ g }{14 \ g/cm^3}[/tex]
The units of grams cancel.
[tex]v= \frac {7 }{14 \ cm^3}[/tex]
[tex]v= \frac {1}{2} \ cm^3[/tex]
The volume of the solid is 1/2 or 0.5 cubic centimeters.
what more accurate model of the atom emerged from Albert Einstein's contributions and quantum mechanics
Answer:
Einstein also in 1905 mathematically proved the existence of atoms, and thus helped revolutionize all the sciences through the use of statistics and probability. Atomic theory says that any liquid is made up of molecules (invisible in 1905)
Explanation:
Answer:
The discoveries of Albert Einstein led to development in the understanding of the atom through the study of quantum mechanics and the electron cloud. In this model, there is still a nucleus with protons and neutrons. But unlike the Bohr model, the electrons exist in a cloud outside the nucleus, much like the fruit around the pit of a peach.
Explanation:
Which of the following has the least H+ ions in its solution?
A. Carbonic acid solution with a pH of 4.
B. Ethanoic acid solution with a pH of 6.5
C. Ammonia solution with a pH of 12.
D. Hydrochloric acid solution with a pH of 1.
WILL GIVE BRAINLIEST IF CORRECT!!
Answer:
The answer is D. Hydrochloric acid solution with a pH of 1.
Explanation:
I just took the same quiz
Hydrochloric acid solution with a pH of 1. Hence, option D is correct.
What is an acid?An acid is an electrolyte that hydrolyses in water to release hydrogen ions.
The lower the pH the greater the concentration of H+ ions. Hydrochloric acid with a pH of 1 is a strong acid and is highly ionised in solution. It has the most H+ ions.
Hence, option D is correct.
Learn more about acid here:
https://brainly.com/question/13380222
#SPJ5
plz answer fast i beg u
Which are not particles that enable electrical conductivity?
Select one:
a. delocalised electrons
b. molecules
c. mobile ions
Answer:
The correct option is;
a. Delocalised electrons
Explanation:
The particles that enable electrical conductivity are the delocalised electrons
The metallic structure consists of identically shaped elements having positive ions that have a resultant alignment, surrounded by a vast array of deloclised electrons, which move freely in the metallic structure such that a metallic part usually has a high electrical conductivity.
Therefore, the freely moving delocalised electron in a metal give them the property of good conductors of electricity.