Answer:
E = 1.89×10⁻¹⁹ J
Explanation:
Given data:
Wavelength of photon = 105 nm (105 ×10⁻⁹ m)
Energy of photon = ?
Solution:
Formula:
E = hc/λ
h = plancks constant = 6.63×10⁻³⁴ Js
c = speed of wave = 3×10⁸ m/s
by putting values,
E = 6.63×10⁻³⁴ Js ×3×10⁸ m/s / 105 ×10⁻⁹ m
E = 19.89×10⁻²⁶ J.m / 105 ×10⁻⁹ m
E = 0.189×10⁻¹⁷ J
E = 1.89×10⁻¹⁹ J
if you wanted to look at a cell wall which type of cell would you observe
Answer:
You could observe the cell wall in all kingdoms except for the animals. That would be cells of plants, protists (algae), fungi, bacteria and achaea.
Help with this question
Answer:
So the number of protons equals the number of electrons.
Explanation:
Ionic bond, also called an electrovalent bond, type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound. Such a bond forms when the valence (outermost) electrons of one atom are transferred permanently to another atom.
The specific heat of iron is 0.46 J/g°C. How many joules will it take to make the temperature of a 150. g bar go up from 25°C to 60.°C?
Answer:
Q = 2.415kj
Explanation:
Q = Mc∆temperature
c = 0.46j/g°c = 0.46kj/kg°c
mass = 150g = 0.15kg
∆temperature = 60 - 25 = 35°c
Q = 0.15 X 0.46 X 35 = 2.415kj
Q = 2.415kj
What is the average atomic mass of strontium
The answer is 87.62 u
Answer:
Atomic number: 38
Electrons per shell: 2,8,18,8,2
Symbol: Sr
Which generally describes granite?
A. Dark colored rock with low silica content
B. Dark colored rock with high silica content
C. Light colored rock with low silica content
D. Light colored rock with high silica content
Answer:
I THINK IT MIGHT BE B
Explanation:
how many group and periods are there in modern periodic table
Answer:
there is 7 periods and 18 groups
Explanation:
which is least likely to be reduced?
A. Zn^2+
B. Fe^3+
C. Cu^2+
D. Fe^2+
A. Zn²⁺
Further explanationGiven
Cations of several elements
Required
The least to be reduced
Solution
If we look at the voltaic series:
Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe²⁺-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Fe³⁺-Ag-Pt-Au
The electrode which is easier to reduce than the hydrogen (H2) electrode has a positive sign (E red= +) and is located to the right of the voltaic series (right of H)
The electrode which is easier to oxidize than the hydrogen (H2) electrode and is difficult to experience reduction has a negative sign (E red= -) and is located to the left of the voltaic series (left of H)
Or you can look at the standard reduction potential value of the metals in the answer options, and the most negative reduction E° value which will be difficult to reduce.
The Zn metal is located far left of the other metals in the answer choices, so it is the most difficult to reduce
difference between proton and electron
a proton is a type of particle with a positive charge and an electron is a particle with a negative charge. neutrons ould be a neutral particle.
What is the name of this atom's model that is commonly used by
Chemistry students to show the basic structure of an atom?
"Plum Pudding model" by JJ Thomson
"Bohr's Model" by Neils Bohr
"Rutherford's Model" by Ernest Rutheforf
Answer:
It is the "Bhor's Model"
Explanation:
Nearly two-thirds of the students ranked the electron cloud and Bohr-model as their two most preferred representations. Students invoked ideas from classical mechanics to interpret the electron cloud model and used probabilistic language to describe the Bohr model of the atom.
A template of a Venn diagram representing common and differentiating characteristics of covalent and ionic bonds is shown.
Which of the following characteristics can be written only in space B?
a)Occurs in substances that have at least one non-metal
b) Occurs in substances that have a repeating lattice structure
c) Occurs in substances that have discrete molecular structure
d) Occurs in substances that have high melting points
It ISNT occurs in substances that have discrete molecular structure
Explanation:
I took the test and got this wrong
A cone has a diameter of 4 inches and a height of 7 inches. Find the volume
of the cone. Use 3.14 for II.
Volume of a cone: II rh
177.2 in.
29.3 in.3
351.7 in.
87.9 in.
Answer:
V = 29.3 inch³
Explanation:
Given data:
Diameter of cone = 4 inch
Height of cone = 7 inch
Volume of cone = ?
Solution:
Formula:
V = πr²h/3
we calculate the radius from diameter,
r = 4 inch/2 = 2 inch
Volume:
V = 3.14 ×(2 inch)² × 7 inch/3
V = 3.14 × 4 inch² × 7 inch/3
V = 29.3 inch³
Which statement best describes a primary occurrence in an uncontrolled fission reaction.
Incomplete question. Options;
A) Mass is created and energy is released.
B) Mass is created and energy is stored.
C) Mass is converted to energy, which is released.
D) Mass is converted to energy, which is stored.
Answer:
Mass is converted to energy, which is released
Explanation:
Basically, when uncontrolled nuclear fission (splitting) occurs, a radioactive atom (a mass) is split into two smaller nuclei leading to a continuous chain of fission reactions.
In other words, as the fission of the mass of the atom continues to occur, the mass is converted to energy, which is then released and more reactions occur.
Hello! Please help.
Is air an element, compound, or mixture?
Is Hydrochloride Acid an element, compound, or mixture?
Oh if you can could you put the explanation of one of them, thank you!
Answer:
Air is a mixture. Its constituents can be separated. For example: oxygen, nitrogen etc.
Hydrochloric acid is a mixture, being an acidic liquid.
Hadron colliders are able to add protons in an element. When a proton is added to an existing element then;
1.An ion is formed with same number of electrons
2. Another isotope of the element is formed with same number of neutrons
3. A second nucleus is formed with more neutrons
4. Another element is formed with greater atomic number
Answer:
4. Another element is formed with greater atomic number
Explanation:
Ions only have a different amount of electrons and have the same amount of protons and neutrons.
Isotopes only have a difference in neutrons.
However, only a difference in protons will make another element.
Hence, 4 is the answer.
Hope this helped!
Please help! This is due in 10 minutes!
Answer:
Nitrogen-15
Explanation:
To use the correct notation, you need to use the mass number. The mass number is the number of protons plus the number of neutrons. Nitrogen has 7 protons. This isotope of nitrogen has 8 neutrons.
The correct notation is nitrogen-15.
What variable represents specific heat in the equation Q = mCAT?
O A. The variable c
O B. The variable T
C. The variable m
O D. The variable Q
Answer:
the variable A represented specific heat capacity
Answer: The Variable T
Explanation:
How does energy flow through the reef ecosystem?
Molecules in the thermosphere are fast moving because
A.
no gravity to slow them down
B.
they have nothing to bump into
C.
they are pulled by the Sun's gravity
D.
of radiation absorption
Answer:
i think a or b
Explanation:
Select the correct answer.
What is the heat content, q, of the reaction when glucose burns?
OA. q=0
OB. q> 0
O C. q<0
OD. 920
Answer: C. q < 0
Explanation: sorry if I'm wrong
What is the anode of a galvanic cell made with zinc and aluminum?
O A. Aluminum ions
B. Zinc metal
O C. Aluminum metal
D. Zinc ions
Answer:
Aluminum Metal
Explanation:
A P E X states that it is Aluminum Metal 100% right
What is the correct formula for combining Mg2+ and Br1+
Answer: The correct formula is [tex]MgBr_2[/tex]
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here magnesium is having an oxidation state of +2 called as [tex]Mg^{2+}[/tex] cation and bromine [tex]Br^{-}[/tex] is an anion with oxidation state of -1. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral [tex]MgBr_2[/tex].
The cations and anions being oppositely charged attract each other through strong coloumbic forces and form an ionic bond.
How many grams of sodium is equal to 6.92 x 10 21atoms of sodium?
Answer:
[tex]Amount\ of\ Grams = 0.2644 g[/tex]
Explanation:
Given
Element: Sodium
[tex]Atoms = 6.92 * 10^{21}[/tex]
Required
Determine the amount of grams
We start by solving for the number of moles
[tex]Moles = \frac{Sodium\ Atoms}{Avogadro\ Number}[/tex]
[tex]Avogadro\ Number = 6.022 * 10^{23}[/tex]
So, we have:
[tex]Moles = \frac{6.92 * 10^{21}}{6.022 * 10^{23}}[/tex]
[tex]Moles = \frac{6.92 * 10^{21-23}}{6.022}[/tex]
[tex]Moles = \frac{6.92 * 10^{-2}}{6.022}[/tex]
[tex]Moles = 1.15 * 10^{-2}[/tex] moles
Next, we calculate the amount of grams.
Mass per mol of Sodium = 22.98977g/mol
For [tex]1.15 * 10^{-2}[/tex] moles of sodium
[tex]Amount\ of\ Grams = 1.15 * 10^{-2}\ mol * 22.98977g/mol[/tex]
[tex]Amount\ of\ Grams = 1.15 * 10^{-2} * 22.98977g[/tex]
[tex]Amount\ of\ Grams = 0.264382355 g[/tex]
[tex]Amount\ of\ Grams = 0.2644 g[/tex] (approximated)
Hence, there are 0.2644g of sodium in [tex]6.92 * 10^{21}[/tex] atoms
Which of the following is a homogeneous mixture? a. salt water
b. beef stew
c. sand and water
d. soil
Status
Exam
HF is
an acid
a base
neither an
acid nor a
base
Copyright © 2003 - 2020 Acellus Corporation. All Rights Reserved.
Is HF a base, acid or non
Answer:
HF is an acid as it losses hydrogen into the sollution on hydrolysis.
Explanation:
Can somebody plz answer both these questions in this question thanks! only 2 sentences is fine :)
WILL MARK BRAINLIEST WHEOEVER ANSWERS FIRST :DDDD
Answer:
Electricity is made at a generating station by huge generators. The current is sent through transformers to increase the voltage to push the power long distances. The electrical charge goes through high-voltage transmission lines that stretch across the country.
As a river’s slope increases, the power of the river to cause erosion usually decreases. Please select the best answer from the choices provided T F
Answer:
False
Explanation:
It is absolutely false that as the river's slope increases the power of the river to cause erosion usually decreases.
The right statement is vice versa because as the slope of the river increases, the ability of the river to cause erosion increases.
The slope of a river is its gradient. As the slope of a river increases so also is its erosive power. The erosive power of a river depends on gravity. As the river becomes more vertical, then the gravity effect increases. This increases the power the river has for erosion.Answer:
false
Explanation:
just cause its right and i took the test
The atomic number of polassium and
calcium is 19 and 20 respectively and they
belong to the same period.
Who among them would have smaller atomic size
Explanation:
Atomic radius decreases from left to right in a period.
Therefore Calcium would have a smaller atomic size.
What is the problem with O2?
Answer:
It’s one of the most popular mobile networks across the UK, but it seems that O2 is having issues this morning
explanation:
According to Down Detector, the issues started at around 10:41 BST, and are affecting users across the UK.
Of those who reported issues, 74% said they were having problems with their mobile phone, 13% with the network, and 11% with mobile internet.
Speaking to Mirror Online, an O2 spokesperson said: "The earlier issue we experienced where some customers may have had difficulty using mobile data has now been resolved. Our technical teams are continuing to closely monitor the situation. We apologise for any inconvenience."
How can room things in a house save energy? List at least 5 ways in which you can save heat energy. Explain how each one can save heat energy.
Answer:
brainly
Explanation:
Adjust your day-to-day behaviors.
Replace your light bulbs.
Use smart power strips.
Install a programmable or smart thermostat.
Purchase energy efficient appliances.
What is the mass of an object that has a density of 2,86 g/mL and a volume of
75 mL
Answer:
214.5 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volume
From the question we have
mass = 75 × 2.86
We have the final answer as
214.5 gHope this helps you