Answer:
Number of moles
Explanation:
Using the number of moles in chemical reactions, we can determine the quantity of products and even the reactants that are combining to form them.
The number of moles is derived using the expression below is;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Once we establish the number of moles of any of the specie given from the mass and molar mass, we can relate it to any other species.
Scientists are studying ways to improve the efficiency of solar cells by studying a process called photon upconversion . In this process , the energy of two photons can become combined to form a new photon with an energy equal to the sum of the two combined photons . With this process , abundant infrared radiation can be converted into visible light that can be used by solar celis to produce electricity . Suppose an infrared photon with a wavelength of 853 nm were combined with another infrared photon with a wavelength of 935 nm , what would be the wavelength of the new 'combined photon , in nm ?
Answer:
λ = 4.46 x 10⁻⁷ m = 446 nm
Explanation:
Applying Law of Conservation of Energy in this condition, we will get the following equation:
Total Energy of Combined Photons = Energy of 1st Photon + Energy of 2nd Photon
hc/λ = hc/λ₁ + hc/λ₂
hc/λ = hc(1/λ₁ + 1/λ₂)
1/λ = 1/λ₁ + 1/λ₂
where,
λ = wavelength of combined photon = ?
λ₁ = wavelength of 1st photon = 853 nm = 8.53 x 10⁻⁷ m
λ₂ = wavelength of 2nd photon = 935 nm = 9.35 x 10⁻⁷ m
Therefore,
1/λ = 1/(8.53 x 10⁻⁷ m) + (9.35 x 10⁻⁷ m)
1/λ = (0.1172 x 10⁷ m⁻¹) + (0.1069 x 10⁷ m)
1/λ = 0.2241 x 10⁷ m⁻¹
λ = 1/(0.2241 x 10⁷ m⁻¹)
λ = 4.46 x 10⁻⁷ m = 446 nm
Answer:
446
Explanation:
need help please ,thx
Answer:
can you get a picture that is in higher quality? we can't read what it's saying
Which of the following describes the location and energy of all the valence electrons
of electrically-neutral sulfur (S)?
3p4
3s23p4
Зрб
3523pó
Answer:
1s22s22p63s23p4
Explanation:
Sulfur is located in the p block and has 6 valence electrons (the 2 exponent on the 3s and the 4 exponent on the 3p add up to 6)
The location and energy of all the valence electrons of electrically-neutral sulfur ( S ) is 3s₂3p₄.
What is sulfur ?
Chemical element sulfur has the letter S and atomic number 16. It is multivalent, nonmetallic, and plentiful. Sulfur atoms normally combine to create cyclic octatomic molecules, which have the chemical formula S8. At room temperature, elemental sulfur is a crystalline solid that is brilliant yellow.
In addition to being a fungicide and an ingredient in black gunpowder, sulfur is used to vulcanize black rubber. However, the majority of sulfur is utilized in the creation of sulfuric acid, which is arguably the most significant chemical produced by western civilisations.
Sulfur can be found naturally and in metal sulfide ores. Natively, it may be found close to hot springs and volcanoes.
Thus, option B is correct.
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Which of the following aspects of biotechnology is not considered to be a moral or ethical issue
The question is incomplete, the complete question is;
Which of the following aspects of biotechnology is Not considered to be a moral or ethical issue?
a.research and testing on animals
b.cloning living material
c.reducing research cost
d.damaging the environment
Answer:
c.reducing research cost
Explanation:
Ethical issues arise when a particular course of action is at odds with the generally acceptable moral standard in the society.
Research and testing on animals is contested as an ethical issue by animal rights activists.
Cloning living material is prohibited among some sections of society and is also being contested as an ethical issue.
Damaging the environment the environment owing to biotechnology research is generally regarded as an ethical issue.
However, reducing research cost is highly acceptable in any research. It does not pose an ethical issue.
Which subatomic particles are stolen and/or shared when atoms bond together during a chemical reaction?
A. protons
B. Subatomic particles are not involved in atomic bonding
C. neutrons
D. electrons
Answer:
D. electrons
Explanation:
Chemical bonds occur as a result of electrons (negatively-charged subatomic particles) being transferred among atoms. The transfer happens when electrons are being stolen or shared from an atom to another. The reason behind this is because atom's atomic shells are naturally inclined to be full. Thus, if one atom has extra electrons, that atom will most likely share his electrons to another atom lacking in it.
You complete titration of 15.0ml of unknown acid with 14.16ml of 1.25 M NaOH. What’s the molar it’s of the unknown acid? Assume the acid is monoprotic 1 mole of acid reacts with 1 mole of base.
The molarity of the unknown acid : 1.18 M
Further explanationTitration is a procedure for determining the concentration of a solution by reacting with another solution that is known to be concentrated (usually a standard solution). Determination of the endpoint/equivalence point of the reaction can use indicators according to the appropriate pH range
Titration formula
M₁V₁n₁=M₂V₂n₂
monoprotic acid⇒n₁=1
NaOH monoprotic base⇒n₂=1
[tex]\tt M_1\times 15=1.25\times 14.16\\\\M_1=1.18~M[/tex]
5. You add 11.00 mL of 0.800 M NaOH to 50.00 mL of pure water, and to this mixture you then add 3.00 mL of 0.200 M HCl. What will be the pH of the resulting solution
Answer:
pH = 13.11
Explanation:
NaOH reacts with HCl to produce H2O and NaCl. pH depends of this reaction. The reactant in excess determine the pH of the solution:
NaOH + HCl → H2O + NaCl
1 mole of NaOH reacts with 1 mole of HCl
To determine limiting reactant we need to find moles of each reactant:
Moles NaOH:
0.011L * (0.800 mol / L) = 0.0088 moles NaOH
Moles HCl:
0.003L* (0.200mol / L) = 0.0006 moles HCl
That means limitng reactant is HCl and moles in excess of NaOH are:
0.0088moles NaOH - 0.0006 moles = 0.0082 moles NaOH =
0.0082 moles OH⁻
In 11.00mL + 50.00mL + 3.00mL = 64.00mL = 0.06400L
[OH-] = 0.0082 moles OH- / 0.064L = 0.1281M OH-
pOH = -log [OH-] = 0.89
pH = 14 - pOH
pH = 13.11How does rusting differ from a combustion reaction?
O A. Rusting involves combining with oxygen, and combustion does not.
O B. Although both involve combining with oxygen, combustion is more rapid. O C. Combustion involves combining with oxygen, and rusting does not. O D. Rusting is a redox reaction, and combustion is not.
Answer:
B. Although both involve combining with oxygen, combustion is more rapid.
Explanation:
Both rusting and combustion involves are combination in which a substance reacts with oxygen.
The difference between both processes is that burning is a rapid process. Oxygen combines with a fuel in a very fast rate. Rusting is a slow process and it takes time. Water vapor is often needed for this reaction to take place. The rate at which combustion occurs is more rapid compared to slow, rusting process.Answer:
B. Although both involve combining with oxygen, combustion is more rapid
Explanation:
a p e x
2.(04.01 LC)
Fill in the blank with the correct number to balance the equation: KClO3 - 2KCI + 302. (Enter only a whole number.) (3 points)
Answer:
2KClO3 —> 2KCl + 3O2
The coefficients are 2, 2, 3
Explanation:
From the question given above, we obtained the following equation:
KClO3 —> 2KCl + 3O2
The above equation can be balance as follow:
There are 2 atoms of K on the right side and 1 atom on the left side. It can be balance by putting 2 in front of KClO3 as shown below:
2KClO3 —> 2KCl + 3O2
Now, the equation is balanced.
Thus, the coefficients are 2, 2, 3
all matter has physical and chemical properties. These properties can be used to identify the type of matter. Which of these statements describe a physical property?
Explanation:
Physical properties of matte tells us everything about a substance when no change is occurring to its constituents.
Such properties are best observed with our senses. Also, physical properties can be observed using equipment in the laboratory or some apparatus.
Examples of these properties are state of matter, color, odor, taste, texture, hardness, solubility in water, melting point, boiling point, density, viscosity and spectroscopic patterns.Please help. What masses of KCl and H2O are needed to make 250 g of 5.00 % solution?
____ g of KCl
____ g of H2O
Answer:
Therefore, in a 250 g of solution, 5% needs to be KCl, i.e. 5% x 250 = 12.5 g of KCl is needed.
Explanation:
Consider the following reaction at equilibrium :
NO_2 (g)+CO (g)↔NO(g)+CO_2 (g) . suppose the volume of the system is decreased at a constant temperature, what change will this cause in the system?
Answer: No shift will occur
I need the full reason
If the volume of the system is decreased, no shift will occur
Further explanationIn the equilibrium system, according to Le Chatelier, if there is a reaction there will be action
Reaction = - action
The reaction taken by the system is to shift the reaction to the right or left.
The composition of chemical reactions in equilibrium can be influenced by temperature, pressure, and concentration.
While on the change in pressure(volume), then the addition of pressure, the reaction will shift towards a smaller reaction coefficient ((the fewest moles of gas )
This pressure usually affects the gas equilibrium system(only count the number of moles of gases)
Reaction
NO₂ (g)+CO (g)↔NO(g)+CO₂(g)
The reactant side of the equation has 2 moles of a gas(1 mole NO₂ and 1 mole CO) ; the product side has 2 moles (1 mole NO and 1 mole CO₂)
So the total number of moles from both sides is the same(2 moles) so that the change in volume (pressure) does not change the direction of equilibrium⇒No shift will occur
How does the asthenosphere interact with the tectonic plates at a divergent boundary?
Answer:
Its D
Explanation:
Why do atoms form ionic and covalent bonds?
Explanation: an ionic bond, is when a atom basically gives a electron to another, forms when one atom becomes stable by losing its outer electrons and the other atoms become stable by gaining the electrons covalent bonds form when sharing atoms results in the highest stability possible
What does a detergent do to water to help the bubbles last
Answer:
Detergent lowers the surface tension of water enough so that bubbles can form. ... Glycerin makes stronger, longer-lasting bubbles, but corn syrup is often substituted in bubble solutions because it is cheaper.
Explanation:
Hope this helps.
It reduces the [surface] tension of the water to form bubbles
A sample of air at 58.6 kPa is expanded from 250 mL to 655 mL. If thetemperature remains constant, what is the final pressure in kPa?
Answer:
22.366 kPaExplanation:
The final pressure can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
Since we are finding the final pressure
[tex]P_2 = \frac{P_1V_1}{V_2} \\[/tex]
From the question
58.6 kPa = 58600 Pa
We have
[tex]P_2 = \frac{58600 \times 250}{655} = \frac{14650000}{655} \\ = 22366.4122... \\ = 22366[/tex]
We have the final answer as
22.366 kPaHope this helps you
Land is a natural resource because it is used by living things to meet their needs. O True
O False
Answer:
Absolutely True :) cause we use it all the time
Land is a natural resource because it is used by living things to meet their needs. The given statement is true.
What is natural resource?Natural resources are important commodities and are used on a global scale. This includes the extraction and purification procedures that allow for their usage in economic production or consumption. Land is a natural resource.
Natural resources can be either renewable (meaning there will eventually be more supply available after they are refilled) or non-renewable (meaning there won't be any more available supply to be harvested from once they run out). Land is a natural resource because it is used by living things to meet their needs. The given statement is true.
Therefore, the given statement is true.
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Calculate the percent yield of (4-chlorophenyl)bis(4-methoxyphenyl)methanol if the actual isolated mass is 0.15 g.
Answer:
This question is incomplete
Explanation:
This question is incomplete. However, in order to calculate the percentage yield of an extraction/isolation, the formula to be used is below
percent yield = isolated mass/total mass × 100
The mass of the yield (which can also be referred to as isolated mass) was provided to be 0.15 g but the total mass of the (4-chlorophenyl)bis(4-methoxyphenyl)methanol was not provided.
In the completed question that has the total mass or the values to obtain the total mass, the formula mentioned earlier should be used.
Which one of the following orbitals in an atom has the lowest energy: a. 6p b. 4f C. 5d d. 7s
An atom of oxygen has six valence electrons. In nature, oxygen is a diatomic molecule and is usually found in the form O2. Why would one atom of oxygen want to bond with another one?
A) When the oxygen atoms bond together, they become ionized.
B) The transfer electrons to each other so they both have a full shell of valence electrons.
C) When oxygen atoms share electrons the outer shell of electrons is filled and each atom becomes more stable.
D) A single atom of oxygen is very stable and simply joins with another oxygen in order to destabilize both of them.
Answer:
I think the answer is B
Explanation:
Answer:
oxygen atom is a unstable atom so it gets attached to other oxygen atom sharing valance electrons to become stable
C is the right ans
Sulfuric acid (H2SO4) has a molar mass of 98.1 g/mol. How many oxygen atoms are found in 75.0 g of H2SO4?
Answer:
18.33 ×10²³ atoms
Explanation:
Given data:
Molar mass of sulfuric acid = 98.1 g/mol
Mass of sulfuric acid = 75.0 g
Number of of oxygen atom present = ?
Solution:
Number of moles of sulfuric acid:
Number of moles = mass/molar mass
Number of moles = 75.0 g/ 98.1 g/mol
Number of moles =0.761 mol
one mole of sulfuric acid contain four mole of oxygen atom.
0.761 mol × 4 = 3.044 mol
1 mole = 6.022×10²³ atoms of oxygen
3.044 mol × 6.022×10²³ atoms of oxygen / 1mol
18.33 ×10²³ atoms
Which number represents an acidic pH, 4 or 9? _______ Numerical Answers Expected! Answer for Blank 1:
Answer:
4
Explanation:
pH scale of acidic is 4.
Answer: 4
Explanation:
Earth magnetic poles are not in the same place as the geographic poles. True or false
Answer:
TRUE!
Explanation:
Which reaction is represented by the net ionic equation for the combination of aqueous solutions of LiNO3 and NaC2H3O2?
Answer:
This question is incomplete
Explanation:
This question is incomplete but the completed question is in the attachment below. To determine the net ionic equation, one must first write the complete equation which is shown below
LiNO₃ + NaC₂H₃O₂ ⇒ LiC₂H₃O₂ + NaNO₃
The ionic equation represented from the above equation will be
Li¹⁺ NO₃⁻ + Na¹⁺ C₂H₃O₂¹⁻ ⇒ Li¹⁺ C₂H₃O₂¹⁻ + Na¹⁺NO₃¹⁻
Because the resultant NaNO₃ formed is an ionic compound (which does not form a molecule), the correct option from the options provided is the first option
Question 4 of 5
Zinc (Zn) combines with hydrogen chloride (HCI) to form
hydrogen gas (H2) and zinc chloride (ZnCl2).
Which equation represents this chemical reaction?
A. ZnCl2 + Zn - H2 + 2HCI
B. Zn - H2 + ZnCl2 + 2HCI
C. Zn + 2HCI - H2 + ZnCl2
D. 2HCl - H2 + Zn + ZnCl2
Answer:
Required Answer:-First rewrite the sentence that defines the equationZinc (Zn) combines with hydrogen chloride (HCI) to form hydrogen gas(H2) and zinc chloride (ZnCl2).
Chemical Equation[tex]\sf Zinc+Hydrogen\:Chloride \longrightarrow Hydrogen\:gas+Zinc\:Chloride[/tex]
Now write the equation[tex]\sf Zn+HCL \longrightarrow H_2+ZnCl_2 [/tex]
Balance[tex]\sf Zn+2HCL\longrightarrow H_2+ZnCl_2 [/tex]
option C is correctAnswer:
Explanation:
Answer is C
List the three subatomic particles. Give the relative masses and charges of each (sorry for putting it in college TvT)
Answer:
Explanation:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
relative charge = -1
Relative mass = 1.1836
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
He constructed the glass tube and create vacuum in it. He applied electric current between electrodes. He noticed that a ray of particles coming from cathode to wards positively charged anode. This ray was cathode ray.
Properties of cathode ray:
The ray is travel in straight line.
The cathode ray is independent of composition of cathode.
When electric field is applied cathode ray is deflected towards the positively charged plate.
Hence it was consist of negatively charged particles.
While neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Relative mass of proton= 1
Relative mass of neutron = 1
Relative mass of proton = +1
Relative charge of neutron = 0
The number of electron or number of protons are called atomic number while mass number of an atom is sum of protons and neutrons. The umber of protons and electrons are always equal to make the atom electrically neutral.
During the reaction: Mg(s) + CuSO4(aq)
es)
MgSO4(aq) + Cu(s), what changes occur to magnesium?
A)Its oxidation number changes from +2 to 0 and it is reduced.
B)Its oxidation number changes from 0 to +4 and it is reduced.
C)Its oxidation number changes from 0 to +2 and it is oxidized.
D)Its oxidation number changes from +2 to +4 and it is oxidized.
Answer:
C
Explanation:
I did it on usatestprep
Assuming that Coca-Cola has the same specific heat as water [4.18 J/(g°C)]. Calculate the amount of heat in kilojoules transferred when one can (about 350 gg) is cooled from 21°C to 8°C.
Answer:
Heat transferred in the process is 19019J
Explanation:
Using the equation:
Q = S×m×ΔT
We can solve the energy transferred in the process, Q, where:
S is specific heat = 4.18J /(g°C)
m is mass = 350g
ΔT is change in temperature (21°C - 8°C = 13°C)
Q = 4.18J/(g°C)×350g×13°C
Q = 19019J
Heat transferred in the process is 19019JThe doctor ordered 300 mg of clopidogrel P.O. STAT.the drug on hand is clopidogrel 75 mg/ TAB. How many tablets are you going to give to your patients?
Answer:
You would give four tablets of clopidogrel 75 mg/TAB STAT.
Waves of sound energy move ________ ___ ____ ___________ from the source.
Answer:
are there any options for us to choose from? or is it just fill in the blank
Waves of sound energy move in the form of vibration from the source of sound energy.
What is waves?Waves is a kind of disturbance that can travel through a medium from one point to another point.
Sound waves is also a type of wave in which energy is travelled from one point to another point through the vibration from the source of sound.
Hence energy travel in the form of vibration.
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