Answer:
1.
First of all, let's convert the energy of the absorbed photon into Joules:
The energy of the photon can be rewritten as:
where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
Re-arranging the formula, we can solve to find the wavelength of the absorbed photon:
2. 1.24 eV
In this case, when the electron jumps from the n=4 level to the n=3 level, emits a photon with wavelength
So the energy of the emitted photon is given by the formula used previously:
and using
we find
converting into electronvolts,
Explanation:
Calculate the molar mass of NaNO3-
how can balancing equations support the law of conservation
Answer:
detail is given below.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
The given equation is balanced chemical equation of photosynthesis. There are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
If equation is not balanced,
CO₂ + H₂O → C₆H₁₂O₆ + O₂
It can not follow the law of conservation of mass because mass is not equal on both side of equation.
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What are 3 ways you know something is living
How the calculation of the [OH-], pH and % ionization for 0.619 M ammonia (NH3) NH3 + H2O (liq) rightwards harpoon over leftwards harpoon NH4+ + OH- Kb = 1.8 x 10-5
Answer:
[OH⁻] = 3.34x10⁻³M; Percent ionization = 0.54%; pH = 11.52
Explanation:
Kb of the reaction:
NH3 + H2O(l) ⇄ NH4+ + OH-
Is:
Kb = 1.8x10⁻⁵ = [NH₄⁺] [OH⁻] / [NH₃]
As all NH₄⁺ and OH⁻ comes from the same source we can write:
[NH₄⁺] = [OH⁻] = X
And as [NH₃] = 0.619M
1.8x10⁻⁵ = [X] [X] / [0.619M]
1.11x10⁻⁵ = X²
3.34x10⁻³ = X = [NH₄⁺] = [OH⁻]
[OH⁻] = 3.34x10⁻³M% ionization:
[NH₄⁺] / [NH₃] * 100 = 3.34x10⁻³M / 0.619M * 100 = 0.54%
pH:
As pOH = -log [OH-]
pOH = 2.48
pH = 14 - pOH
pH = 11.52Can somebody Please Help
Answer:
5425440 μm
Explanation:
From the question given above,
Length (in ft) = 17.8 ft
Length (in μm) =?
Next, we shall convert 17.8 ft to in. This can be obtained as follow:
1 ft = 12 in
Therefore,
17.8 ft = 17.8 ft × 12 in / 1 ft
17.8 ft = 213.6 in
Next, we shall convert 213.6 in to cm. This can be obtained as follow:
1 in = 2.54 cm
Therefore,
213.6 in = 213.6 in × 2.54 / 1 in
213.6 in = 542.544 cm
Finally, we shall convert 542.544 cm to μm. This can be obtained as follow:
1 cm = 10⁴ μm
Therefore,
542.544 cm = 542.544 cm × 10⁴ μm / 1 cm
542.544 cm = 5425440 μm
Therefore, 17.8 ft is equivalent is equivalent to 5425440 μm
How many moles are in 9.07 x 10^23 atoms of sodium chloride?
Answer:
1.5 moles of sodium chloride are present.
Explanation:
Given data:
Number of moles of sodium chloride = ?
Number of atoms of sodium chloride = 9.07×10²³
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
9.07×10²³ atoms × 1 mol / 6.022 × 10²³ atoms
1.5 moles of sodium chloride are present.
The reaction of Pb+4 and O-2 produces the compound of
a
Pb2O2
b
PbO
c
Pb2O
d
PbO2
Answer:
Pb₂O₄
Explanation:
The given species are:
Pb⁴⁺ O²⁻
Now, to solve this problem, we use the combining powers which corresponds to the number of electrons usually lost or gained or shared by atoms during the course of a chemical combination.
Pb⁴⁺ O²⁻
Combining power 4 2
Exchange of valencies 2 4
Now the molecular formula is Pb₂O₄
A solution with a molarity of 0.1850 contains 19.30 grams of BaCl2. What is the volume of the solution
Answer:
Volume in L = 0.50 L
Explanation:
Given data:
Molarity of solution = 0.1850 M
Mass of BaCl₂ = 19.30 g
Volume of solution = ?
Solution:
First of all we will calculate the number of moles of solute:
Number of moles = mass/molar mass
Molar mass of BaCl₂ = 208.23 g/mol
Number of moles = 19.30 g / 208.23 g/mol
Number of moles = 0.093 mol
Volume of solution:
Molarity = number of moles of solute / volume of solution in L
0.1850 M = 0.093 mol / Volume in L
Volume in L = 0.093 mol / 0.1850 M (M= mol/L)
Volume in L = 0.50 L
When coal is burned, carbon atoms are moved from the geosphere to the atmosphere. Each atom of carbon in the coal combines with two atoms of oxygen to produce carbon dioxide (CO2). Carbon dioxide has an atomic weight of 44, which is approximately 3.667 times heavier than a carbon atom of atomic weight 12.
It takes about 4750 pounds of coal to power a house for one year. If anthracite coal is used, how many pounds of carbon will this be?
Answer:
5*10^25 atoms of carbon
Explanation:
When ammonium nitrate (NH4NO3) explodes, the products are nitrogen, oxygen, and water. When 50.0
grams of ammonium nitrate explode, 22.0 grams of nitrogen and 8.0 grams of oxygen form. How many
grams of water form?
Answer:
( NH4NO3 -> N2+O2+H2O)
Explanation:
40g= 14g+8g+X
x=18g
hope that helps :)
4. Will competition for food increase or decrease carrying
capacity?*
O A. decrease
O B. increase
In an electrically neutral atom of any element, there are equal numbers of
A. Protons and neurons.
B. electrons and procons.
C. electrons and neurrons.
D. atomic number and atomia mess. 5
Answer:
B. electrons and protons.
Explanation:
In an electrically neutral atom of any element, there are equal number of protons and electrons in the atom.
Protons are the positively charged particles in an atom.
Electrons are the negatively charged particles within the atom.
When the number of protons and electrons are the same or equal, the atom is neutral.
But when there is an imbalance, an ion results.
how many molecules are in 18moles of CH.
Answer:
1.08 x 10²⁵molecules
Explanation:
From the mole concept we know that ;
1 mole of any substance contains 6.02 x 10²³ molecules
This number is the Avogadro's number.
So;
18 mole of CH will contain:
Number of molecules of CH = 18 x 6.02 x 10²³ = 1.08 x 10²⁵molecules
The number of molecules is therefore 1.08 x 10²⁵molecules
39 Which statement is NOT a part of the scientific theory of cells?
A Cells are the basic unit of life.
B All cells come from other cells.
C All organisms are made of cells.
D Cells make up nonliving objects.
Answer: D
Explanation: cells are alive
Answer:
D
Explanation:
Cells are the most basic unit of life.
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Answer:
sample 2
Explanation:
hope this helps
When an atom is charged, it is called an ion. How many electrons are in O^2-?
Answer:
10 electrons
Explanation:
Sulphur is found in many forms in the nature. S2, S6 and Ss being some of them. What can we say
will certainly be common among these forms of sulphur?
(A) They will exhibit same physical properties
(B) They will exhibit same chemical properties
(C) Sulphur atoms in each will be identical
(D) All of the above
Answer:
What can be said about these common forms of sulphur is that;
(B) They will exhibit same chemical properties
Explanation:
Allotropy is the property of an element to exist in two or more forms in the same physical state
Allotropes have several similar chemical properties but differ in their physical properties, such as the white, pale yellow to totally colorless diamond and the gray graphite
Sulphur can exist in several allotropic forms, and carbon is the only element that has more allotropes than sulphur
The sulphur allotropes includes S₂, S₆, and S₅ have similar chemical properties but different physical properties.
The correct option is;
What can be said about these common forms of sulphur is that they have the same chemical properties
If you start with substance A and substance B, combine them together,
and produce a new substance C, you have witnessed a
Answer:
Chemical change
Explanation:
If you start with substance A and B and you produce C, you have witnessed a chemical change and this is a synthesis or combination reaction.
A + B → C
We know this because from the two different reactants, a new substance C has been formed.
The substance C is produced via a chemical change.
In a chemical change, new kinds of products are usually formed and the reaction is not easily reversible.
What happened when you placed your bottle system
in cold water?
Answer:
The water level in the pipe went down.] ... [The hot water in the cup heated up the water particles inside the bottle. They began to move more. Greater motion (kinetic energy) pushed the particles farther apart, resulting in expansion.
What kind of statement is," Roller coasters are the best to use of Newton's laws of motions
Answer:
An opinion.
Explanation:
In physics, Sir Isaac Newton's first law of motion is known as law of inertia and it states that, an object or a physical body in motion will continue in its state of motion at continuous velocity (the same speed and direction) or, if at rest, will remain at rest unless acted upon by an external force.
The statement, "Roller coasters are the best use of Newton's laws of motions" is an opinion because it is not based on any evidence, facts or has a proof to back it up.
In English literature, an opinion is considered to be more like a claim.
A claim can be defined as a statement that is used by a writer to prove, substantiate or support an argument. Thus, a claim is an assertive statement expressed by a writer to prove that an argument is true or real.
A 1.0 kg ball is thrown into the air and initial velocity of 30 mi./s how high into the air did the ball travel
Answer:
45.9m
Explanation:
Given parameters:
Mass of the ball = 1kg
Initial velocity = 30m/s
Unknown:
Height the ball will travel = ?
Solution:
At the maximum height, the final velocity of the ball will be 0;
Using ;
V² = U² - 2gh
V is the final velocity
U is the initial velocity
g is the acceleration due to gravity
h is the height
0² = 30² - (2 x 9.8 x h)
0 = 900 - 19.6h
h = 45.9m
What is electrical energy?
O A. Energy stored in a molecule
B. Energy released by a temperature change
O c. The movement of electrons
O D. The sound from an explosion
If two types of matter are combined and energy is given off, what type of change is likely to have occurred?
Answer:
Chemical change
Explanation:
If two types of matter reacts or are combined and energy is given off, the type of change that might have occurred is a chemical change.
A chemical change is one in which a new kind of matter is formed.
It is always accompanied by energy changes.
The process is not easily reversible.
When an exothermic reaction or change occurs, heat is released and it is a typical characteristic of chemical change.
How does the number of molecules in 1 mol of oxygen compare with the number of molecules in 1 mol of nitrogen?
1 mol of oxygen has fewer molecules.
1 mol of oxygen has more molecules.
Each sample has the same number of molecules.
The molecules cannot be compared without knowing the mass.
Answer:
Each sample has the same number of molecules.
Explanation:
Just took the quiz on edge 2021
Taking into account the definition of Avogadro's number, each sample has the same number of molecules.
Avogadro's NumberAvogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole.
Avogadro's number applies to any substance.
This caseAvogadro's number applies to any substance. This means that the number of molecules in 1 mol of oxygen is equal to the number of molecules in 1 mol of nitrogen.
Finally, the correct answer is the third option: each sample has the same number of molecules.
Learn more about Avogadro's Number:
brainly.com/question/1445383
brainly.com/question/1528951
which of the following is not a way to measure a race car motion
a) it’s deceleration
b) it’s velocity
c) the car’s resistance
d) the car’s displacement
The following that is not a way to measure a race car's motion is its velocity. The correct option is b.
What is motion?
Motion is a phenomenon that changes the position of an object with respect to time. The motion needs a force to change the position, and motion needs some energy that can be potential energy or a force.
Velocity is the speed of any object that is in motion in a particular direction. It tells the rate of change of motion of an object. It is a scalar quantity.
Motion is the result of force. Force can be measured by multiplying the mass by acceleration. So the variables that would be needed to calculate a race car's motion will be acceleration and the mass of the car, and the resistances.
Thus, the correct option is b. it’s velocity.
To learn more about motion, refer to the link:
https://brainly.com/question/3421105
#SPJ2
Metals bond with halogens to form colorless metal halides. During an experiment, chlorine water was added to a solution of potassium bromide. A record of the experiment is shown.
Experimental Record
Reactants Color of Reactants Color of Reactants after Mixing
cl,
Colorless solution
Deep yellow-orange colored solution is formed
KBT Colorless solution
Which of the following conclusions can be made about this chemical reaction based on the data? (1 point)
O Chlorine is more reactive than bromine.
Potassium bromide and chlorine do not react.
O Potassium metal is formed from a single replacement reaction.
O Bromine solution is colorless and is formed due to a single replacement reaction.
Answer:
O Chlorine is more reactive than bromine.
Explanation:
From this experiment we can conclude that chlorine is more reactive than bromine and it is the reason why the reaction is able to proceed.
The reaction is a single displacement reaction in which the position of an element in the activity series is very important. Since chlorine is more electronegative and highly reactive when compared to bromine, it will displace bromine from the solution of potassium bromide. So, we have product of potassium chloride and the bromide.How does heat gases cause increase in pressure?
A. Molecules increase in pressure as heat is applied.
B. Heat energy cause less molecule to collide with each other increasing pressure.
C. As molecules move more due to increase in heat, they bump into each other more create pressure.
D. Molecules move less in heated gas producing more pressure.
Answer:
Explanation:
A is the correct answer.
If you found my answer useful then please mark me brainliest
Answer:
I put this so the guy up top can have brainliest
Explanation:
your welcome
Why does your heart rate increase while exercising?
Answer:
During exercise, your body may need three or four times your normal cardiac output, because your muscles need more oxygen when you exert yourself. During exercise, your heart typically beats faster so that more blood gets out to your body.
Answer:
I'd myself say it's because a lot of people are fat but here's the real answer ;)
During exercise, your body may need three or four times your normal cardiac output, because your muscles need more oxygen when you exert yourself. During exercise, your heart typically beats faster so that more blood gets out to your body.
Differentiate between 4 H2O and H8O4
Answer:
How many atoms of hydrogen and oxygen are in 2 molecules of water? ... 7) Using complete sentences, explain the difference between the chemical ... (s) solid, (l) liquid, (g) gas, (aq) aqueous solution (dissolved in water).
Explanation:
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