Answer:
The answer is
[tex] \huge 7.40 \times {10}^{21} Hz[/tex]
Explanation:
To find the frequency of the wave we use the formula
[tex]f = \frac{E}{h} \\ [/tex]
where
E is the energy
f is the frequency
h is the Planck's constant which is
6.626 × 10-³⁴ Js
From the question
E = 4.90 × 10-¹² J
So we have
[tex]f = \frac{4.90 \times {10}^{ - 12} }{6.626 \times {10}^{ - 34} } \\ [/tex]
We have the final answer as
[tex]7.40 \times {10}^{21} \: \: Hz[/tex]
Hope this helps you
Help :( the blue boxes are clickable
Answer:
I am sure they are why won't they
Choose all the answers that apply.
Ionic compounds _____.
-do not dissolve in water
-have high melting points
-have low melting points
-dissolve easily in water
-conduct electricity when melted
Answer:
high melting points, dissolve easily in water, conduct electricity when melted.
Explanation:
I'm pretty sure
Which element is classified as a noble gas?
Answer:
The elements with completely filled shells are classified as noble gases
That is why we only see noble gases on the rightmost corner of the periodic table, it is because they have the maximum number of electrons in a shell
Examples of noble gases
Helium , Neon , Argon and Krypton are some examples of noble gases
Answer:
D. (Xe) XenonExplanation:
I JUST TOOK THE TEST!
PLEASE PLEAS HELP Which of the following compounds is insoluble in water?
a) ZnSO4
b) K2SO4
c) Na2CO3
d) Ag2CO3
Answer:
Your answer is d
Explanation: silver carbonate Ag2CO3 is insoluble in water
What was one main point of Dalton’s atomic theory?
A. That atoms were made up of positive and negative charges
B. That atoms changed as they formed compounds
C. That atoms has a nucleus at the center
D. That atoms made up the smallest form of matter
The main point of Dalton’s atomic theory is that the atoms are made up the smallest form of matter. Hence Option (D) is Correct
What is Dalton's Atomic Theory ?
The 5 main points of Dalton's Atomic theory was ;
Elements are composed of extremely small particles called atoms that are indivisible and indestructibleAll atoms of a given element are identical; they have the same size, mass, and chemical propertiesAtoms of 1 element are different from the atoms of all other elementsCompounds are composed of atoms of more than 1 element. The relative number of atoms of each element in a given compound is always the same.Chemical reactions only involve the rearrangement of atoms. Atoms are not created or destroyed during chemical reactions.Therefore, The main point of Dalton’s atomic theory is that the atoms are made up the smallest form of matter. Hence Option (D) is Correct
Learn more about Atom here ;
https://brainly.com/question/657632
#SPJ2
Answer:
D is correct
Explanation:
The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the
А.
electron
B
proton
neutron
D
atom
Answer:
The answer is D - Atom
The smallest unit of an element that can exist either alone or in combination with other such particles of the same or different elements is the atom.
What is an atom?
An atom is defined as the smallest unit of matter which forms an element. Every form of matter whether solid,liquid , gas consists of atoms . Each atom has a nucleus which is composed of protons and neutrons and shells in which the electrons revolve.
The protons are positively charged and neutrons are neutral and hence the nucleus is positively charged. The electrons which revolve around the nucleus are negatively charged and hence the atom as a whole is neutral and stable due to presence of oppositely charged particles.
Atoms of the same element are similar as they have number of sub- atomic particles which on combination do not alter the chemical properties of the substances.
Learn more about atom,here:
https://brainly.com/question/13654549
#SPJ2
SOMEONE PLEASE HELPPP
How many atoms of Chlorine are in 1.00 mol of Chlorine gas?
6.022 x 10∧23
3.01 x 10∧23
6.022 x 10∧24
Answer:
6.02 × 10²³ atoms Cl₂
Explanation:
Avagadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
Step 1: Define
1.00 mol Cl₂ (g)
Step 2: Use Dimensional Analysis
[tex]1.00 \hspace{3} mol \hspace{3} Cl_2(\frac{6.02(10)^23 \hspace{3} atoms \hspace{3} Cl_2}{1 \hspace{3} mol \hspace{3} Cl_2} )[/tex] = 6.02 × 10²³ atoms Cl₂
The heat of fusion for naphthalene is 0.148 kJ/g. Calculate the heat energy in joules required to melt 52.95 g of naphthalene.
Answer:
7836.6 J
Explanation:
The following data were obtained from the question:
Heat of fusion (Hf) = 0.148 KJ/g
Mass (m) = 52.95 g
Heat (Q) required =..?
The heat (Q) required to melt the sample of nephthalene can be obtained as follow:
Q = m·Hf
Q = 52.95 × 0.148
Q = 7.8366 KJ
Finally, we shall convert 7.8366 KJ to Joule (J) in order to obtain the desired result. This can be obtained as follow:
1 kJ = 1000 J
Therefore,
7.8366 KJ = 7.8366 KJ × 1000 J / 1 KJ
7.8366 KJ = 7836.6 J
Therefore, 7.8366 KJ is equivalent to 7836.6 J
Thus, 7836.6 J of heat energy is required to melt the sample of nephthalene.
The heat required for melting of 52.95 g of naphthalene has been 7.8366 kJ.
The heat of fusion has been the energy required by 1g for the change in the substance.
The heat required to melt naphthalene can be given as:
Heat = mass × Heat of fusion
The given mass = 52.95 g
The heat of fusion = 0.148 kJ/g
The heat required can be given as:
Heat = 0.148 × 52.95 kJ
Heat = 7.8366 kJ.
The heat required for melting of 52.95 g of naphthalene has been 7.8366 kJ.
For more information about the heat of fusion, refer to the link:
https://brainly.com/question/25475410
Which of the following represents a species with 16 protons and 18 electrons? A) Ar B) S C) S²⁻ D) Si⁴⁻ E) S²⁺ Question 5 of 40
Answer:S²⁻
Explanation:
Sulphur is in group 16. The atomic number of sulphur is 16.
However, sulphur can accept two electrons to form the sulphide ion S²⁻ which contains 18 electrons, hence the answer provided above.
is a renewable resource used for the generation of electricity.
A. Natural gas
B. Coal
C. Petroleum
O D. Biomass
Answer:
its natural gas because i had something like this
Explanation:
The renewable energy sources, such as biomass, geothermal resources, water, wind, etc. are called the natural resources. These can be converted into clean and usable energy. The correct option is D.
What is Renewable energy?The energy which is derived from the natural sources which are replenished at a higher rate than they are consumed is defined as the Renewable energy. The renewable energy generating produce lower emissions than burning the fossil fuels.
The word biomass refers to the organic plant matter which is converted into fuel and used as an energy source. The biomass fuel is considered as an important renewable and sustainable source of energy. It is used for the production of electricity.
The organic materials like wood, agricultural wastes, etc. acts as the excellent sources to produce biomass fuel. It is possible to burn the biomass fuel directly and later converted into methane and ethanol biofuels.
Thus the correct option is D.
To know more about renewable energy, visit;
https://brainly.com/question/13258101
#SPJ7
Please help me!!!:)))
Answer:
blocks 1 and 2 the rhdh huff hgfhh5
A solution has a pH of 6. What is true about the solution?
A. It is a strong basic solution.
B. It is a weak acidic solution.
C. It is a weak basic solution.
D. It is a strong acidic solution.
please help me
Answer:
A. it is a strong basic solution
Answer:
(see below)
Explanation:
First, refer to the pH scale:
1 2 3 4 5 6 7 8 9 10 11 12 13 14
<== acidic neutral basic ==>
You can see that the smaller the number, the stronger the acid and the bigger the number, the more basic the base is. 7 is neutral, such as water. it's neither basic nor acidic.
Now, using the process of elimination:
A) It's a strong basic solution.
No, because this solution's pH hasn't even reached basic.
B) It's a weak acidic solution.
Yes, because it is acidic and it's just a little bit more acidic than a neutral solution.
C) It's a weak basic solution.
No, because this solution's pH hasn't even reached basic.
D) It's a strong acidic solution.
No, because even though it's acidic, it's just below neutral. For something to be a strong acidic solution would be around a pH of 3.
So the answer would be B) It's a weak acidic solution.
Which element contains one set of paired and three unpaired electrons in its fourth and outer main energy level?
Explanation:
Phosphorus (P) because of the 5 valence electrons total, 3 of them are in the 3p sublevel, and according to Hund's rule, they "single-fill" each orbital first.
Violet light has a wavelength of 4.50 x 10-12 m. What is the frequency?*
3 points
1.5 x10^20 1/s
0.0135 1/s
6.77x10^19 1/5
3x10^8 1/s
Green light has a frequency of 6.73 x 1014 1/s. What is the wavelength?*
3 points
2.24x10^6 m
4.46x10^-7 m
2.02 x 10^23 m.
4.95 x 10^-24 m
3 points
What is the energy (Joules) of violet light with a frequency = 3.43 x 10^14
1/s? *
4.54x10^-19 J
1.99x10^-25 J
1.93 x 10^-48 J
2.27 x 10^-19 J
Answer:
Frequency = 6.67x10¹⁹ s⁻¹
Wavelength = 4.46x10⁻⁷m
e = 2.27x10⁻¹⁹J
Explanation:
To convert frequency to wavelength and vice versa we use the equation:
Wavelength = Speed of light / Frequency
Speed ligth is 3x10⁸m/s
For a wavelength of 4.50x10⁻¹²m:
4.50x10⁻¹²m = 3x10⁸m/s / Frequency
Frequency = 3x10⁸m/s / 4.5x10⁻¹²m
Frequency = 6.67x10¹⁹ s⁻¹For a frequency of 6.73x10¹⁴s⁻¹:
Wavelength = 3x10⁸m/s / 6.73x10¹⁴s⁻¹
Wavelength = 4.46x10⁻⁷mAnd energy, e, from frequency, is obtained as follows:
e = h ₓ frequency
Where h is Planck's constant, 6.626x10⁻³⁴J*s
e = 6.626x10⁻³⁴J*s*3.43x10¹⁴s⁻¹
e = 2.27x10⁻¹⁹JWhat is the heat gjoules transferred by a chemical reaction to the reservoir of a calorimeter containing 135g of dilute aqueous solution (c=4.184 J/g^ C) the reaction causes the temperature of the reservoir to rise from 23.0 27.0 degrees * C
Answer:
Required heat = 2,259.36 N (approx)
Explanation:
Given:
Mass = 135 g
Specific heat (c) =4.184 J/gC
Change in temperature ΔT = 27-23 = 4 c
Find:
Required heat
Computation:
Q = mcΔT
Q = (135)(4.184)(4)
Required heat = 2,259.36 N (approx)
The heat transferred by the chemical reaction to the reservoir of a calorimeter containing 135 g of dilute aqueous solution is 2259.36 J
To solve this question, we'll begin by calculating the change in the temperature of the reservoir. This can be obtained as follow:
Initial temperature (T₁) = 23 °C
Final temperature (T₂) = 27 °C
Change in temperature (ΔT) =?ΔT = T₂ – T₁
ΔT = 27 – 23
ΔT = 4 °CFinally, we shall determine the heat transferred to the reservoir.
Change in temperature (ΔT) = 4 °C
Mass (M) = 135 g
Specific heat capacity (C) = 4.184 J/gºC
Heat (Q) =?Q = MCΔT
Q = 135 × 4.184 × 4
Q = 2259.36 JTherefore, the heat transferred by the chemical reaction to the reservoir of a calorimeter containing 135 g of dilute aqueous solution is 2259.36 J
Learn more: https://brainly.com/question/10286596
The discharge of chromate ions (CrO42-) to sewers or natural waters is of concern because of both its ecological impacts and its effects on human health if the receiving water is later used as a drinking water source. One way in which chromate can be removed from solution is by its reaction with ferrous ions (Fe2+) to form a mixture of chromic hydroxide and ferric hydroxide solids [Cr(OH)3(s) and Fe(OH)3(s), respectively], which can then be filtered out of the water. The overall reaction can be represented as
CrO42- + 3 Fe2+ + 8 H2O --> Cr(OH)3(s) + 3 Fe(OH)3(s) + 4 H+
How much particulate matter would be generated daily by this process at a facility that treats 60 m3/h of a waste stream containing 4.0 mg/L Cr, if the treatment reduces the Cr concentration enough to meet a discharge limit of 0.1 mg/L?
Answer:
45727g
Explanation:
So, have the overall ionic equation given as the following;
CrO42^- + 3 Fe2^+ + 8 H2O ------> Cr(OH)^3(s) + 3 Fe(OH)^3(s) + 4 H^+.
So, we have (from the question) that the amount or quantity of the waste stream daily = 60m^3/h, and the waste stream daily contains waste stream containing = 4.0 mg/L Cr, and the discharge limit = 0.1 mg/L.
Step one: convert m^3/ h to L/h. Therefore, 60 m^3/h × 1000dm^3 = 60000 L/h .
Step two: Determine or calculate the the value of Cr used up.
The value of Car used up ={ 60,000 × ( 4.0 - 0.1) } ÷ 1000 = 234 g.
Step three: Determine or calculate the mass of Cr(OH)3 and the mass of Fe(OH)3.
The number of moles of Cr = 234/52 = 4.5 moles.
Molar mass of Cr(OH)3 = 103 g/mol and the molar mass of Fe(OH)3 = 106.8 g/mol.
Thus, the mass of Cr(OH)3 = 4.5 × 103 = 463.5 g.
And the mass of Fe(OH)3 = 13.5 × 106.8 = 1441.8 g.
Hence, the total = 463.5 g + 1441.8 g = 1905.3 g.
Step four: Determine or calculate the How much particulate matter would be generated daily.
The amount of the particulate that would be generated daily = 24 × 1905.3 = 45727g.
The atoms of which element will gain electrons to form an ion?
oxygen
calcium
lithium
mercury
Explanation:
Oxygen will gain electrons to form ion (O²⁻).
Calcium loses electron to form ion (Ca²⁺)
Lithium loses electron to form ion (Li⁺)
Mercury loses electron to form ion (Hg²⁺)
Here it is stated in question that the element will gain electron it means electron bears negative charge.
Therefore,
Option A is correct ✔.
20
How do you determine the number of barium atoms in the formula below?
4Ba(OH)2
F
# of Ba atoms = coefficient 4 + subscript 1 = 5
G
# of Ba atoms = coefficient 4 X subscript 1 = 4
H
# of Ba atoms = subscript 4 X coefficient 2 = 6
# of Ba atoms coefficient 1 + subscript 1 = 2
J
Answer:
G is correct option:
# of Ba atoms = coefficient 4 × subscript 1= 4
Explanation:
Formula:
4Ba(OH)₂
G is correct option:
# of Ba atoms = coefficient 4 × subscript 1= 4
Because there are only 4 atoms of Ba in given formula.
Ba(OH)₂ contain one atom of Ba while in question there are 4 moles of Ba(OH)₂ present thus total 4×1 = 4 atoms of Ba present.
Other options are incorrect. Because,
F:
# of Ba atoms = coefficient 4 + subscript 1 = 5
This shows given formula contain 5 Ba atoms. So it is incorrect.
H:
# of Ba atoms = subscript 4 × coefficient 2 = 6
This shows that subscript is 4 which is incorrect because coefficient is 4 and subscript is 1.
j:
# of Ba atoms = subscript 1 + coefficient 1 = 2
This option shows that subscript is one which is correct but coefficient is incorrect. The coefficient of Ba is 4 and coefficient is always multiply with subscript not added. So this option is also incorrect.
A liquid has a volume of 62.7 mL and a density of 2.59 g/mL. What is its mass? (show all work)
Answer:
162.4
Explanation:
The formula for mass is density* volume so 62.7 multiplied by 2.59 equals 162.393. then you round so your anwser would be 162.4
Which is denser a liquid or solid why?
Answer:
Liquids are usually less dense than solids but more dense than air. Temperature can change a liquid's density. For example, increasing the temperature of water causes the molecules to spread farther apart. The farther apart the molecules are, the less dense the water is.
Answer:
Solids are usually much more dense than liquids and gases, but not always.
Explanation:
Mercury, a metallic element that is a liquid at room temperature, is denser than many solids. Aerogel, a very unusual human-made solid, is about 500 times less dense than wate
How many moles would be in 24.23 grams of SrSO4?
Use two digits past the decimal for all values.
Answer:
about 0.13 mol
Explanation:
To find number of mols when given grams you first have to find the molar mass of the compound. This is done by adding up the atomic masses of the element in the compound. So Sr= 88 g/mol S=32 g/mol and O=16 g/mol. Then 88+32+(16x4)=184. Then using this you can convert from grams to mols by dividing the grams by the molar mass. So, 24.23/184 equals about 0.13 mol.
You are given 3 liquid samples – A, B, C and told that one is water, one is ethanol, and one is ether (d=0.700 g/mL). Each sample is 10.0 mL. the masses are as follows: A = 10.0 g, B= 7.00 g, C = 8.00 g. Identify each of the substances using density problems.
Answer:
im just trying to get work done i will help u if i knew it
Which of the following evidence supports the theory of plate tectonics
Answer:
seafloor spreading
Explanation:
i took the test
State Hess' law of constant heat summation.
(b) Calculate the enthalpy of formation of CH4 from the following data:
i) C(s) + O2(g) → CO2(g); ∆H = -393.7 kJ/mol
ii) H2(g) + 1⁄2 O2(g) → H2O(l); ∆H = -285.8 kJ/mol
iii) CH4(g) + 2 O2(g)→ CO2(g) + 2H2O(l); ∆H = -890.4 kJ/mol
Answer:
-74.6 kj/mol
Explanation:
you can see the answer at the pic
A scientist plans to find out the cause of decrease in bird population in a location. He interviews 50 people who work in the local oil mine and 45 of them believe that the mine does not affect the birds. The scientist concludes that 90 percent of people in the location believe that the local oil mine does not cause decrease in bird population. Why is the scientist's conclusion most likely unreliable? (2 points)
Group of answer choices
a. the results of the investigation cannot be repeated
b. the source of information could be biased
c. bird population cannot be measured accurately
d. the investigation is done by only one person
Answer:
Explanation:
Which of the following contribute(s) to most of the mass of an atom? Question 5 options: A) Neutrons only B) Protons and electrons C) Protons and neutrons D) Protons only
Answer:
C
Explanation:
Hope this helps :)
Given the mass of carbon on the periodic table (12.01 amu), which isotope do you think is the most abundant? Explain WHY in complete sentences. *
Answer:
Carbon-12
Explanation:
Carbon-12 is a carbon with 6 protons and 6 neutrons. Since the AMU for an element is calculated by averaging all naturally occurring isotopes, we can see that 12 in the most abundant. (Since 12.01 is very close to 12, the only reason it is not exactly 12 is because there are other isotopes like carbon-13 or carbon-14 but in low amounts)
All good experiments should be...
Define a function compute_gas_volume that returns the volume of a gas given parameters pressure, temperature, and moles. Use the gas equation PV
Answer:
def compute_volume(pressure,moles,temperature):
volume = (8.314 * moles * temperature)/pressure
print("Volume: "+str(volume))
Explanation:
This line defines the function
def compute_volume(pressure,moles,temperature):
This line calculates the volume
volume = (8.314 * moles * temperature)/pressure
This line prints the calculated volume
print("Volume: "+str(volume))