Answer:
be.77.0kj.
Explanation:
add moles then times
Considering the definition of enthalpy of vaporization, the correct answer is option c. the heat required to vaporize 15.8 g of CH₃OH at its boiling point is 18.8 kJ.
When a material changes phase from solid to liquid, or from liquid to gas, a certain amount of energy is involved in this phase change.
In case of phase change from liquid to gas, this amount of energy is known as enthalpy of vaporization (symbolized as ∆H vap), also known as (latent) heat of vaporization or heat of evaporation.
In other words, the enthalpy of vaporization is the amount of energy required to change a unit of mass (for example, moles or kg) of a substance from phase liquid to phase gas at constant temperature and pressure.
In this case, you know that enthalpy of vaporization is ∆Hvap = 38.0 kJ/mol.
On the other side, you want to vaporize 15.8 g of CH₃OH. Then, being the molar mass of the compound 32 g / mole (that is, the amount of mass contained in one mole), the number of moles to be vaporized is:
[tex]15.8 gramsx\frac{1 mol}{32 grams}= 0.49375 moles[/tex]
Then, the heat required to vaporize 0.49375 moles of CH₃OH at its boiling point is calculated taking into account the enthalpy of vaporization by:
0.49375 moles× 38.0 kJ/mol= 18.76 kJ ≅ 18.8 kJ
Finally, the correct answer is option c. the heat required to vaporize 15.8 g of CH₃OH at its boiling point is 18.8 kJ.
Learn more:
https://brainly.com/question/21655944?referrer=searchResultshttps://brainly.com/question/7580155?referrer=searchResultshttps://brainly.com/question/4035699?referrer=searchResultshttps://brainly.com/question/11475740https://brainly.com/question/2212655?referrer=searchResultsNuclide A has a half-life of 4 days, and nuclide B has a half-life of 16 days. At the beginning of an experiment, a sample contains 2 nuclei of nuclide A and 218 nuclei equal of nuclide B. How long will it take before the numbers of nuclei of the two nuclides are equal?
Answer:
can't say...... . . please make me as brainlist
Answer: ladadadadadadasasasasassassaasss
Explanation:
i poop my pants
Anyone know how to do this please!! ? I will mark brainlist
Which pair of elements have the same valence electronic configuration of np³?
(a)O and Se (b)Ge and Pb (c)P and Sb (d)K and Mg (e)Al and Ga
Answer:
(c) P and Sb
Explanation:
We can determine the number of valence electrons of an element:
If it belongs to Groups 1 and 2, the number of valence electrons is equal to the number of group and the differential electron occupies the s subshell.If it belongs to the groups 13-18, the number of valence electrons is equal to: "Number of group - 10" and the differential electron occupies the p subshell.Which pair of elements have the same valence electronic configuration of np³?
(a) O and Se. NO. They belong to the group 16 and the valence electron configuration is ns² np⁴.
(b) Ge and Pb. NO. They belong to the group 14 and the valence electron configuration is ns² np².
(c) P and Sb. YES. They belong to the group 15 and the valence electron configuration is ns² np³.
(d) K and Mg. NO. They belong to the groups 1 and 2 and the valence electron configuration is ns¹ and ns².
(e) Al and Ga. NO. They belong to the group 13 and the valence electron configuration is ns² np¹.
The pairs of elements that contain the similar valence electronic should be option (c) P and Sb
Valence electronic configuration:In the case when it belongs to Groups 1 and 2, the no of valence electrons should be equivalent to the number of groups and the differential electron occupies the s subshell. On the other hand, in the case when it belongs to the groups 13-18, the number of valence electrons should be equivalent to "Number of group - 10" and the differential electron occupies the p subshell.
This question is incomplete. Please find the completed question below.
Which pair of elements have the same valence electronic configuration of np³?
(a) O and Se. NO. They belong to the group 16 and the valence electron configuration is ns² np⁴.
(b) Ge and Pb. NO. They belong to the group 14 and the valence electron configuration is ns² np².
(c) P and Sb. YES. They belong to the group 15 and the valence electron configuration is ns² np³.
(d) K and Mg. NO. They belong to the groups 1 and 2 and the valence electron configuration is ns¹ and ns².
(e) Al and Ga. NO. They belong to the group 13 and the valence electron configuration is ns² np¹.
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What do good electrical conductors and thermal conductors have in common?
Write a paragraph.
Answer:
A material that readily transmits energy is a conductor, while one that resist energy transfer is called an insulator. There are different types of conductors and insulators because there are different forms of energy. Materials that conduct electrons, protons, or ions are electrical conductors. They conduct electricity. Usually, electrical conductors have loosely bound electrons. Materials that conduct heat are thermal conductors. Substances that transfer sound are acoustical conductors. There are corresponding insulators for each type of conductor.
Explanation:
Electrical conductors and thermal conductors have loosely bound electrons. These are the materials that conduct heat.
Electrical conductors and thermal conductors:Electrical conductivity is a measure of how well electrical current can pass through a material under the influence of an applied electric field. Thermal conductivity measures how well heat can pass through a material under a temperature difference. Materials that are good conductors of heat and electricity. Thermal insulators do not transfer energy, but thermal conductors do.
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Helppppppppppp ASAP
Answer:
c
Explanation:
its c bcs they are both the same
The lattice energy for ionic crystals increases as the charge on the ions _____________ and the size of the ions __________________.
a. increases, increases
b. increases, decreases
c. decreases, increases
d. decreases, decreases
e. none of these ,is generally correct
Answer:
b. increases, decreases
Explanation:
For an ionic compound ( ionic crystal), the lattice energy accounts for the crystal lattice's cohesion energy.
The lattice energy is the change in molar enthalpy associated with the reaction of the formation of gas ions from a mole of crystal.
This means that the lattice energy is needed to split the bond between particles of a solid ionic crystal and change the atoms into gaseous ions.
The smaller the atom size, the more heat energy required to split the bond, and the larger the atom size, the lesser heat required.
The charge on the atom also affects the behavior of ionic crystals. In essence, the higher the charge on the atom, the more difficult to split the bond, and the lesser the charge on an atom, the easier it is to split the bond.
Thus, we can conclude that the lattice energy for ionic crystals increases as the ions' charge increases, and the size of the ions decreases.
For the chemical reaction 2 HBr(aq) + Ba(OH), (aq) — 2H20(1) + BaBr, (aq) write the net ionic equation, including the phases. net ionic equation:
Answer:
2hbr(aq) + ba(OH)2 (aq) --.> 2 H20 (l) + Babr2 (aq)
ionic equation is follows
2H^+(aq) + 2Br^- (aq) + Ba^2+(aq) + OH^-(aq) --->2H2O(l) + Ba^2+(aq) + 2Br-(aq)
cancel the spectator ions in equation above, that is Ba^2+ and 2Br^- ions
the net ionic equation is therefore=
2H^+(aq) + OH^-(aq)---> 2H2O (l)
Which statement is a scientific law?
Scientists use genes to explain why evolution happens.
Genes are long patterns that are similar to computer codes.
A person’s traits are controlled by different forms of a gene.
The discovery of genes changed how scientists think about life.
**PLEASE heLP i NEED THESE ANSWERSSSSSSSS*
How do you think the size of an atom will affect its ability to attract additional electrons?
There are many ways of generating electrical energy. Research three of the following, describe how they work, and discuss the pros and cons of each of the three chosen electrical power plants:
thermal power plant (aka coal power plant)
nuclear power plant
solar power plant
hydroelectric power plant
geothermal power plant
tidal power plant
wind farms
Answer: Thermal Power Plant 1. A thermal power station is a power station in which heat energy is converted to electric power. In most, a steam-driven turbine converts heat to mechanical power as an intermediate to electrical power. Water is heated, turns into steam and drives a steam turbine which drives an electrical generator.
Nuclear Power Plant 2. A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical of thermal power stations, heat is used to generate steam that drives a steam turbine connected to a generator that produces electricity.
Solar Power Plant 3. Solar thermal power/electric generation systems collect and concentrate sunlight to produce the high temperature heat needed to generate electricity. ... Solar thermal power plants may also be hybrid systems that use other fuels (usually natural gas) to supplement energy from the sun during periods of low solar radiation.
Hydroelectric Power Plant 4. The most common type of hydroelectric power plant is an impoundment facility. An impoundment facility, typically a large hydropower system, uses a dam to store river water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity.
Geothermal Power Plant 5. At a geothermal power plant, wells are drilled 1 or 2 miles deep into the Earth to pump steam or hot water to the surface. ... When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam. The steam spins a turbine, which is connected to a generator that produces electricity.
Tidal Power Plant 6. There are very few commercial-sized tidal power plants operating in the world. The first was located in La Rance, France. The largest facility is the Sihwa Lake Tidal Power Station in South Korea. The United States has no tidal plants and only a few sites where tidal energy could be produced at a reasonable price.
Wind Farm 7. Wind turbines work on a simple principle: instead of using electricity to make wind—like a fan—wind turbines use wind to make electricity. Wind turns the propeller-like blades of a turbine around a rotor, which spins a generator, which creates electricity.
Explanation:
To solve this we must be knowing each and every concept related to thermal power plant. Therefore, in the below given ways, three ways of producing electricity is discussed.
What is thermal power plant?A power plant that converts heat energy into electric power is known as a thermal power station. Most often, a steam-driven turbine turns heat into mechanical power as a step toward creating electricity.
Systems for generating electricity using solar thermal energy collect and start concentrating sunlight to create the high-temperature heat required to produce electricity.
An impoundment facility is the kind of hydroelectric plant that is most prevalent. A dam is used in an impoundment facility, which is usually a big hydroelectric system, to hold stream water in a reservoir.
Therefore, in the above given ways, three ways of producing electricity is discussed.
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For an electron that interacts with visible light, which visible photon would give the most accurate (lowest error) measurement of momentum (or speed)?
blue
yellow
green
orange
violet
Answer:
violet
Explanation:
When an electron interacts with visible light, energy is transferred from the photon to the electron.
The most accurate (lowest error) measurement of momentum (or speed) of an electron is obtained using a photon of high energy and low wavelength.
Violet light which lies at the high energy end of spectrum is most suitable.
the range of a visible wavelength is
Answer:
380 to 700 nanometers
Explanation:
The visible light spectrum is the segment of the electromagnetic spectrum that the human eye can view. More simply, this range of wavelengths is called visible light. Typically, the human eye can detect wavelengths from 380 to 700 nanometers.
Hope that answers your question.
How do valence electrons influence electrical conductivity?
Answer:
The conductivity of the atom depends on the number of electrons that are in the valence shell. When an atom has only one electron in valence shell, it is almost a perfect conductor. When an atom has eight valence electrons the valence shell is said to be complete and the atom is an insulator.
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What is the electron configuration for an atom on Period #3 and in Group #17?
1s22s22p63523p64523d
1s22s22p?
1s22s22p 3s23p
1s22s22p
p64523d5
Answer:
the answer the question is 2,8,7
. All waves have a similar
Which statement about Fe is supported by the modern atomic theory but not John Dalton’s theory?
A. The element iron is composed of small particles called atoms.
B. The electrons of iron have probable locations in a region of space around the nucleus.
C. Iron atoms combine with other atoms in whole number ratios to form compounds.
D. Chemical reactions that involve iron do not create new atoms of iron.
Answer:
The correct option is B
Explanation:
One of the claims of John Dalton's atomic theory is that atom is the smallest unit of matter (which suggests that there are no particles smaller than an atom in any matter). This claim has been disproved by the modern atomic theory which established that there are particles smaller than atom (called subatomic particles). These particles are electrons, protons and neutrons.
One of the modern atomic theory was by Neils Bohr, who proposed that electrons move in circular orbits around the central nucleus. Thus, the electrons of iron can also be said to be present in a region of space (circular path) around the nucleus. This proves that option B is the correct option as John Dalton's theory did not even recognize the electron(s) nor the nucleus.
Answer:
b
Explanation:
You are the medical examiner at the scene of a murder at a restaurant. There is a
suspicion that the victim was poisoned. Their blood contained the following %
composition 80.66%-c, 7.39%-H, 9.39 %-N, and 2.68%-o Which of the following
compounds was the cause of the murder?
The compound : C₄₀H₄₄N₄O
Further explanationThe empirical formula is the smallest comparison of atoms of compound =mole ratio of the components
The principle of determining empirical formula
• Determine the mass ratio of the constituent elements of the compound.
• Determine the mole ratio by dividing the percentage by the atomic mass
The mol ratio of composition : C : H : N : O
[tex]\tt \dfrac{80.66}{12}\div \dfrac{7.39}{1}\div \dfrac{9.39}{14}\div \dfrac{2.68}{16}\\\\6.722\div 7.39\div 0.671\div 0.1675\rightarrow divide~by~smallest(0.1675)\\\\40\div 44\div 4\div 1[/tex]
HELP ASAPP
Use the periodic table to choose the pair of elements whose properties are most
similar.
A. Silicone (SI), Phosphorous (P)
B. Chlorine (CI), Iodine (1)
C. Potassium (K), Magnesium (Mg)
D. Neon (N), Sulfur (S)
Answer:
B.chlorine (Cl), iodine (I)
Energy travels in what direction?
Which statement describes the reason for removing the insulation from the
ends of the wires used to make an electromagnet?
A. the ends of the wires become magnetic when the insulation is removed
B. The wires are easier to handle after insulation has been removed from them
C. The metal of the wires must be in contact with the terminals of a battery
D. the insulation on the wires causes the direction of an electric current to reverse
Answer:
The answer is different for other people so look out.The answer here is C. The metal of the wires must be in contact with the terminals of a battery.
Explanation:
I took the quiz.
The metal of the wire must be in contact with the terminals of a battery so that, electrons can easily pass through and generate the electrical current.
What is electrical insulation?An electrical insulation is used to prevent the passage of electricity through an object. The materials which does not conduct electrically at any condition is called insulators.
Insulators are used as protective envelopes over the conducting bodies to resist the electrical shock and shortage of electricity. The electrical wires of circuits are coated with insulating plastics throughout up to the terminals.
The terminals cannot be insulated because, the passage of electricity to external circuit can only be achieved by conducting ends otherwise insulation will resist the passage of electrons to the battery. Thus, option C is correct.
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In a reaction, 25 g of reactant AB breaks down into 10g of Product A and an unknown amount of Product B. What is the mass of product B?
Answer:
Mass of product B = 15g
Explanation:
Reaction:
AB → A + B
Mass of AB = 25g
Mass of A = 10g
Unknown:
Mass of B = ?
Solution:
Based on the law of conservation of matter "matter is neither created nor destroyed but transformed from one form to another in a chemical reaction".
The amount of product = amount of reactant
Mass of AB = Mass of A + Mass of B
Now;
Mass of Product B = Mass of AB - Mass of A
Mass of product B = 25 - 10 = 15g
Mass of product B = 15g
If 4.74 g of propane is allowed to completely combust, calculate the mass of carbon dioxide formed at the end. Remember the units
Answer:
14.2g
Explanation:
The reaction expression is given as:
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Given mass of propane combusted;
4.74g
Unknown:
Mass of carbon dioxide produced = ?
Solution:
To solve this problem, we find the number of moles of the given propane;
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of C₃H₈ = 3(12) + 8(1) = 44g/mol
Number of moles = [tex]\frac{4.74}{44}[/tex] = 0.11mol
From the balanced reaction equation:
1 mole of C₃H₈ will produce 3 moles of CO₂
0.11mole of C₃H₈ will produce 3 x 0.11 = 0.33mole of CO₂
Mass of CO₂ = number of moles x molar mass
Molar mass of CO₂ = 12 + 2(16) = 44g/mol
Mass of CO₂ = 0.33 x 44 = 14.2g
What di you think you would see happen in the bucket as ice comes into contact with high kinetic energy molecules?
Answer:The ice will melt
Explanation:
Use the chemical equation below to determine how many moles of ammonia
(NH) will be produced from 4 moles of nitrogen gas (N). Assume that there is enough H, for all of the N, to be converted to NHs.
N2 + 3H2 → 2NH
A- 3 moles
B- 8 moles
C- 4 moles
D- 2 moles
Answer:
If we assume that there will be enough Hydrogen for the reaction to occur, then there will be 8 moles of NH
Explanation:
The balanced equation will look like this:
4N2 + 4H2 -> 8NH
PLEASE HELP ASAP
An element has 24 protons and 20 electrons. What is the chemical symbol?
Answer:
Br
Explanation:
what is the reaction of guanine and adenine
Complementary Base Pairing. Specific pairs can only go together, so when guanine and adenine pair up, its Complementry Base Pairing :)
Hope this helps! Please correct me if im wrong :)
Calculate the energy of a photon having a wavelength of 7.71 x 10^-5 m.
Answer:
Calculate the energy of a photon having a wavelength of 7.71 x 10^-5 m.
Explanation:
Draw structures of the major organic products:
Answer:
b only
Explanation:
Which statement best explains the relationship between cellular respiration and photosynthesis? Cellular respiration breaks down glucose, while photosynthesis builds glucose. Photosynthesis breaks down glucose, while cellular respiration builds glucose. Both photosynthesis and cellular respiration break down glucose. Both photosynthesis and cellular respiration build glucose.
Answer:
I think both photosynthesis and cellular respiration breaks down glucose
Explanation:
sorry if i'm wrong
Answer:
c
Explanation:
both photosynthesis and cellular respiration brakes down glucoso
What classifies spiders as Carnivores?
A. They have 6 legs
B. They eat plants
C. They eat meat
D. They get eaten by other organisms
Answer:
c. carnivore means to eat meat
Answer:
c. they eat meat
Explanation:
while the other options are true those don't classify spiders as carnivores