What is in the solar system?
A. All the above
B. asteroids and comets
C. The sun and everything thing that orbits around it
D. planets and their moons
PLEASE HELP
Answers
Answer:
all of the above
Explanation:
all of this is in the solar system
Related Questions
which is a metal that becomes isoelectronic with krypton ?
Answers
A metal which becomes isoelectronic with Krypton when it forms its most common ion is Strontium (Sr2+). The correct option is E.
What is isoelectronic?Isoelectronic species are atoms, elements, ions, or molecules that have an equal number of valence electrons and the same atom connectivity. For example, Carbon Monoxide (CO) and Dinitrogen (N2) are isoelectronic, because both have ten valence electrons.
In this case, from the periodic table we know that Krypton (Kr) has an atomic number equal to 36, which means that a neutral Krypton atom has 36 electrons surrounding its nucleus. Consequently, any species which is isoelectronic with Krypton also have 36 electrons surrounding its nucleus.
For Calcium (Ca), it has 20 electrons. It means Ca2+ will have 2 electrons less, or 18 electrons. So, it is not isoelectronic with Krypton.
For Potassium (K), it has 19 electrons. It means K+ will have 18 electrons. So, it is not isoelectronic with Krypton.
For Iodine (I), it has 53 electrons. It means I- will have 54 electrons. So, it is not isoelectronic with Krypton.
For Magnesium (Mg), it has 12 electrons. It means Mg2+ will have 10 electrons. So, it is not isoelectronic with Krypton.
For Strontium (Sr), it has 38 electrons. It means Sr2+ will have 36 electrons. So, it is isoelectronic with a neutral Krypton atom.
Hence, the one which becomes isoelectronic with Krypton is Strontium (Sr2+).
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Although part of your question is missing, you might be referring to this full question: Which is a metal that becomes isoelectronic with Krypton when it forms its most common ion?
a. Ca2+
b. K+
c. I−
d. Mg2+
e. Sr2+
given that benzaldehyde is a meta- director, in the same marvin editor draw all three resonance structures for the carbocation intermediate that results from step 2 in the electrophilic aromatic substitution reaction when benzaldehyde reacts with br2 in the presence of febr3. if you do not remember the structure of the benzene derivative, consult the l3 complete lecture notes slides
Answers
In the electrophilic aromatic substitution reaction between benzaldehyde and Br2 in the presence of FeBr3, the first step involves the generation of a carbocation intermediate. This carbocation is formed when the bromine molecule attacks the benzene ring, displacing a proton.
Since benzaldehyde is a meta-director, the carbocation intermediate will be stabilized through resonance. The resonance structures can be represented as follows:
Structure 1:
Br
|
Ph-C(+)-H
|
Structure 2:
Br
|
Ph-C-H
| |
+ Ph
Structure 3:
Br
|
Ph-C-H
| |
Ph +
In these resonance structures, the positive charge of the carbocation is delocalized throughout the benzene ring. The presence of the electron-withdrawing aldehyde group (CHO) in benzaldehyde directs the incoming bromine atom to the meta position relative to the aldehyde group.
Please note that it's always recommended to consult reliable sources and appropriate references for accurate structural representations.
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PLZ HELP ME IM FAILING!
Everything you need to know about the question is on the photo
Answers
Answer:
C. NH₄Cl
Explanation:
The compound with the element ratio 1 : 4 : 1 from the given choices is NH₄Cl.
An element is a pure substance made up of distinct number of atoms. Elements are unique and are different from other elements because of the nature of their atoms.
We often delineate an element using chemical symbols.
In the compound NH₄Cl;
There are 3 elements:
Number of atoms
N 1
H 4
Cl 1
How could IR spectroscopy distinguish between 1-hexyne, 2-hexyne, and 3-hexyne? Check all that apply.
2-Hexyne will show neither the absorption band at ∼3300cm−1 nor the one at ∼2100cm−1 (there is no change in dipole moment when the C≡C stretches).
1-Hexyne will show absorption bands at ∼3300cm−1 for a hydrogen bonded to an sp carbon and at ∼2100cm−1 for the triple bond.
3-Hexyne will show the absorption band at ∼2100cm−1 but not the one at ∼3300cm−1.
3-Hexyne will show neither the absorption band at ∼3300cm−1 nor the one at ∼2100cm−1 (there is no change in dipole moment when the C≡C stretches).
1-Hexyne will show the absorption band at ∼2100cm−1 but not the one at ∼3300cm−1.
2-Hexyne will show absorption bands at ∼3300cm−1 for a hydrogen bonded to an sp3 carbon and at ∼2100cm−1 for the triple bond.
1-Hexyne will show neither the absorption band at ∼3300cm−1 nor the one at ∼2100cm−1 (there is no change in dipole moment when the C≡C stretches).
1-Hexyne will show absorption bands at ∼2100cm−1 for a hydrogen bonded to an sp carbon and at ∼3300cm−1 for the triple bond.
2-Hexyne will show the absorption band at ∼2100cm−1 but not the one at ∼3300cm−1.
Answers
1-Hexyne will show absorption bands at ∼3300cm−1 for a hydrogen bonded to an sp carbon and at ∼2100cm−1 for the triple bond.
2-Hexyne will show absorption bands at ∼3300cm−1 for a hydrogen bonded to an sp3 carbon and at ∼2100cm−1 for the triple bond.
3-Hexyne will show the absorption band at ∼2100cm−1 but not the one at ∼3300cm−1.
IR spectroscopy is a technique that measures the vibrational modes of molecules. Each molecule has a unique set of vibrational modes that correspond to different types of bonds within the molecule. In the case of alkynes, the C≡C triple bond is a strong bond that will produce a characteristic peak in the IR spectrum at around 2100 cm^-1. The presence or absence of other peaks will depend on the specific structure of the molecule.
For 1-hexyne, the hydrogen bonded to the sp carbon will produce a peak at around 3300 cm^-1 due to the stretching of the C-H bond. The C≡C triple bond will produce a peak at around 2100 cm^-1.
For 2-hexyne, the hydrogen bonded to the sp3 carbon will produce a peak at around 3300 cm^-1 due to the stretching of the C-H bond. The C≡C triple bond will produce a peak at around 2100 cm^-1.
For 3-hexyne, the C≡C triple bond will produce a peak at around 2100 cm^-1, but there is no hydrogen bonded to an sp carbon, so there will be no peak at around 3300 cm^-1.
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which insecticide has been banned from developed countries? group of answer choices deet pyrethrin boric acid ddt
Answers
DDT (dichlorodiphenyltrichloroethane) is the insecticide that has been banned from developed countries.
DDT was first synthesized in 1874, but its insecticidal properties were discovered in 1939 by Paul Müller, a Swiss chemist. It was widely used during World War II to protect soldiers from malaria, typhus, and other insect-borne diseases.
However, in the 1960s, concerns about the environmental and health impacts of DDT began to emerge. In 1962, American biologist Rachel Carson published her influential book "Silent Spring," which highlighted the dangers of DDT, including its persistence in the environment, its bioaccumulation in the food chain, and its toxic effects on wildlife and humans.
As a result of growing public awareness and scientific evidence, many developed countries, including the United States, started to restrict or ban the use of DDT in the 1970s. The U.S. Environmental Protection Agency (EPA) banned DDT in 1972, and several other countries followed suit.
In 2001, the Stockholm Convention on Persistent Organic Pollutants was adopted, which aims to eliminate or restrict the production and use of persistent organic pollutants, including DDT. Currently, DDT is banned or restricted in most developed countries but is still used in some developing countries to control vector-borne diseases like malaria.
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The complete question is:
Which insecticide has been banned from developed countries?
group of answer choices:
Deet
Pyrethrin
Boric acid
DDT
PLEASE HELP I ACTUALLY WANT TO LEARN THIS PROBLEM!!! 125 g Fe₂O3 reacts according to the equation below. Calculate the % yield if
87,000 milligrams of iron are formed?
Fe₂O3 +
C →
125g Fez03x
Fe +
CO
Answers
To calculate the % yield, you need to determine the actual yield of the reaction and compare it to the theoretical yield. The actual yield is the amount of product that is actually produced during the reaction, while the theoretical yield is the maximum amount of product that could be produced based on the amounts of reactants used.
In this case, the theoretical yield is 87,000 milligrams of iron, since this is the amount of product that was actually produced. The % yield is calculated by dividing the actual yield by the theoretical yield and multiplying by 100%.
Since the actual yield and the theoretical yield are the same in this case, the % yield is 100%. This means that the reaction had a perfect yield, with all of the reactants being converted into product.
Which TWO words complete the gaps? To check if the cracking of a long-chain hydrocarbon has actually produced alkenes, the gas produced can be bubbled through __________ __________.
Answers
To check in case the splitting of a long-chain hydrocarbon has created alkenes, the gas created can be bubbled through natural gas or aromatic rich petroleum gas.
The first beginning of cracking of hydrocarbons is alkanes. The items of splitting incorporate alkanes and alkenes, individuals of a different homologous series.
An alkene could be a hydrocarbon that contains a carbon-carbon twofold bond. The longer alkanes are warmed, and their vapors are passed over a hot catalyst. This causes covalent bonds to break and change.
In thermal breaking, tall temperatures (ordinarily within the run of 450°C to 750°C) and weights (up to approximately 70 climates) are utilized to break the huge hydrocarbons into littler ones.
Thermal splitting gives blends of items containing tall extents of hydrocarbons with two-fold bonds - alkenes.
Catalytic cracking uses a temperature of approximately 550°C and a catalyst known as a zeolite which contains aluminum oxide and silicon oxide. Steam cracking uses a higher temperature of over 800°C and no catalyst.
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if the pco2 in the plasma increases, what effect will this have on plasma ph?
Answers
When the partial pressure of carbon dioxide (pCO2) in the plasma increases, this leads to a decrease in plasma pH, resulting in a more acidic environment. The relationship between pCO2 and pH is described by the Henderson-Hasselbalch equation, which helps predict the acid-base balance in the body.
An increase in pCO2 levels indicates that more CO2 is being produced or less is being eliminated. As CO2 dissolves in the plasma, it forms carbonic acid (H2CO3), which subsequently dissociates into hydrogen ions (H+) and bicarbonate ions (HCO3-). The increase in H+ ions is what causes the decrease in pH, signifying a more acidic environment.
This change in pH can disrupt the body's normal homeostasis and is commonly referred to as respiratory acidosis. The body's response to this imbalance involves various buffering systems, such as the bicarbonate buffer system, to help restore pH to a normal range.
In conclusion, an increase in plasma pCO2 levels leads to a decrease in plasma pH, creating a more acidic environment. This can disrupt the body's normal functioning and prompt compensatory mechanisms to restore the acid-base balance.
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Is this equation balanced? Explain why the equation S+3O2 → SO3 is balanced or is not balanced. Use four different words from the word bank to earn (4 points).
Answers
We can check if the equation is balanced by comparing the number of atoms of each element on the reactant and product sides. The reaction is only balanced if the number of atoms of each element is equal.
S + 3O₂ → SO₃
Reactant Product
S 1 1
O 6 3
∴ the equation is UNBALANCED since the number of atoms of oxygen on the reactant side is greater than that of the product.The balanced equation would be 2 S + 3O₂ → 2SO₃
Reactant Product
S 2 2
O 6 6
question.
Which of the following events must occur at point 6 in order to transform sedimentary rock into igneous rock?
A
Shifting tectonic plates push the sedimentary rock toward the poles, where it freezes and hardens into igneous rock.
B
Extreme winds and storms weather the sedimentary rock into particles, which collect in rivers and are compacted into igneous rock.
C
Rising oceans erode mountains of sedimentary rock into particles, which sink and get compacted into layers that form igneous rock.
D
Tectonic plates push against each other, driving sedimentary rock under Earth's surface, where it melts into magma and turns into igneous rock as it cools
Answers
Answer:
I belive the answer is D
Find the theoretical density of magnesium given that it has a HCP crystal structure, an atomic weight and atomic radius of 24.31 g/mol and 0.16 nm respectively, and c/a ratio of 1.624.
Answers
The theoretical density of magnesium in its HCP crystal structure is 1.738 g/cm³.
To calculate the theoretical density of magnesium, we need to consider its crystal structure, atomic weight, atomic radius, and the c/a ratio.
In the hexagonal close-packed (HCP) crystal structure, the unit cell consists of three layers of atoms stacked in a close-packed arrangement. The c/a ratio represents the ratio of the height (c-axis) to the basal plane edge length (a-axis) of the unit cell.
First, we calculate the volume of the unit cell. Since the HCP structure has a close-packed arrangement, we can approximate the unit cell as a hexagonal prism. The volume of a hexagonal prism can be calculated using the formula: Volume = (√3/2) * a² * c.
Next, we determine the number of atoms per unit cell. In an HCP structure, there are two atoms in the base plane and one atom on top or bottom. Therefore, the number of atoms per unit cell is 3.
To find the theoretical density, we divide the atomic weight by the volume of the unit cell multiplied by the number of atoms per unit cell.
The final calculation gives us the theoretical density of magnesium in its HCP crystal structure as 1.738 g/cm³.
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A process by which softer, less weather-resistant rocks wear away and leave harder, more weather-resistant rocks behind is called a. differential weathering. c. chemical weathering. b. mechanical weathering. d. ice wedging.
Answers
Answer:
geosphere
Explanation:
Answer:
differential weathering.
Explanation:
if 46 g na and 32 g o2 are provided, find the maximum number of moles of sodium oxide produced
Answers
The maximum number of moles of sodium oxide produced is 2.00 moles
The balanced chemical equation for the reaction between sodium and oxygen to form sodium oxide is:
4Na + O2 → 2Na2O
From the equation, we can see that 4 moles of sodium react with 1 mole of oxygen to produce 2 moles of sodium oxide.
To find the maximum number of moles of sodium oxide produced, we need to determine which reactant is limiting.
The molar mass of Na is 22.99 g/mol and the molar mass of O2 is 32.00 g/mol.
Using the given masses, we can calculate the number of moles of each reactant:
moles of Na = 46 g Na / 22.99 g/mol = 2.00 mol Na
moles of O2 = 32 g O2 / 32.00 g/mol = 1.00 mol O2
According to the balanced equation, 4 moles of Na react with 1 mole of O2. Therefore, since we have only 1.00 mol of O2, it is the limiting reactant.
From the equation, we see that 1 mole of O2 reacts to produce 2 moles of Na2O. Therefore, the maximum number of moles of Na2O that can be produced is:
moles of Na2O = (1.00 mol O2) × (2 mol Na2O/1 mol O2) = 2.00 mol Na2O
Therefore, the maximum number of moles of sodium oxide produced is 2.00 moles
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At 1 atm, how much energy is required to heat 65.0 g H, O(s) at -12.0 °C to H, O(g) at 169.0 °C? Use the heat transfer constants found in this table.
Answers
The energy required to heat 65.0 g of H2O(s) at -12.0°C to H2O(g) at 169.0°C is 1500 J.
Mass of H2O, m = 65 g
Initial temperature, T1 = -12°C = 261K
Final temperature, T2 = 169°C = 442K
The specific heat capacity of H2O (s), c = 2.09 J/g K
The specific heat capacity of H2O (l), c = 4.18 J/g K
The specific heat capacity of H2O (g), c = 2.03 J/g K
The heat of fusion of H2O, ΔHfus = 6.01 kJ/mol
The heat of vaporization of H2O, ΔHvap = 40.7 kJ/mol
First of all, we will calculate the heat required to increase the temperature of H2O(s) from -12°C to 0°C;Q1 = mcΔT= (65 g)(2.09 J/g K)(0 - (-12°C))= (65 g)(2.09 J/g K)(12°C)Q1 = 1627.4 J
Now, we will calculate the heat required to melt H2O(s) to H2O(l) at 0°C;Q2 = mΔHfus= (65 g) / [18.015 g/mol)](6.01 kJ/mol)Q2 = 13,571.1 J
Next, we will calculate the heat required to increase the temperature of H2O(l) from 0°C to 100°C;Q3 = mcΔT= (65 g)(4.18 J/g K)(100 - 0°C)Q3 = 27,170 J
Then, we will calculate the heat required to vaporize H2O(l) to H2O(g) at 100°C;Q4 = mΔHvap= (65 g) / [18.015 g/mol)](40.7 kJ/mol)Q4 = 1,497,678.8 J
Now, we will calculate the heat required to increase the temperature of H2O(g) from 100°C to 169°C;Q5 = mcΔT= (65 g)(2.03 J/g K)(169 - 100°C)Q5 = 9,838.35 J
Therefore, the total amount of heat required to heat 65.0 g of H2O(s) at -12.0°C to H2O(g) at 169.0°C is;Q = Q1 + Q2 + Q3 + Q4 + Q5Q = 1,518,285.65 J ≈ 1.52 × 10³ J ≈ 1500 J
Thus, the energy required to heat 65.0 g of H2O(s) at -12.0°C to H2O(g) at 169.0°C is 1500 J.
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the fact that alcohol has a lower boiling temperature than water is important in the process of
Answers
The water and the alcohol will start to evaporate once you start blowing on your hand. Compared with water, alcohol has a lower heat of evaporation.
In the water cycle, evaporation is more important than precipitation.Rain is the fastest way for nature to distribute water in the water cycle. Evaporation from the earth's water surface is required to turn water into air, which will become the cloud, prior to the possibility of rain. The act of condensing will then cause the clouds to turn into rain. The evaporation of water, as opposed to the evaporation of alcohol, involves a greater heat transfer for a given amount of liquid.
the fact that alcohol has a lower boiling temperature than water is important in the process of
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Why does energy need to be inputted for an endothermic reaction?
A)Energy is needed to form bonds
B)Energy is not needed to form or break bonds
C)Energy has nothing to do with making or breaking bonds
D)Energy needs to be inputted to break bonds
Answers
Answer:
I think C option ✔️ ✔️ correct
*pls hurry, will give brainlyest or whatever!!*
Which of the following is an example of a chemical reaction?
The break down of food into energy
Photosynthesis in plants
Milk spoiling
All of the above
None of the Above
Answers
Answer:
all of the above. they all are chemical reactions
A fire that is burning wood will release water vapor and carbon dioxide
true or false?
Answers
Answer:
true.
Explanation:
Which metallic crystal structure has a coordination number of 8
Answers
Answer:
body-centered cubic
Explanation:
:D
which of the following is not a type of secondary battery?select the correct answer below: a. nickel-cadmium b. batteryal kaline c. battery lithium d. ion battery e. these are all types of secondary f. batteries
these are all types of secondary batteries
Answers
The correct answer is e. these are all types of secondary batteries. Alkaline batteries are primary batteries and not a type of secondary battery. Secondary batteries, such as nickel-cadmium, lithium-ion, and others, are rechargeable, whereas primary batteries like alkaline are single-use and cannot be recharged.
The correct answer is "e. these are all types of secondary batteries". All of the options listed, including nickel-cadmium, alkaline, lithium, and ion batteries, are types of secondary batteries. Secondary batteries, also known as rechargeable batteries, can be recharged and reused multiple times, unlike primary batteries which are single-use. They are commonly used in electronic devices such as smartphones, laptops, and portable speakers. It is important to note that not all types of batteries are secondary batteries, as primary batteries such as alkaline and zinc-carbon batteries cannot be recharged.
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Which of these statements accurately describes monomers?
Monomers are macromolecules.
Monomers contain double bonds.
Monomers are made of repeating units.
Monomers contain bonds between metals.
Answers
Answer:
monomers contain double bonds
Explanation:
Answer:
B.Monomers contain double bonds.
Explanation:
Which of the following equations are balanced correctly?
Answers
Answer:
It looks like A is the correct answer. Cu + H2O → CuO + H2
Explanation:
i hope this helps 229 999 0523
explain why zn reacts more slowly with dilute hydrochloric acid then with concentrated hydrochloric acid
Answers
Answer:
When the concentration is higher, more hydrogen ions are near the Zn atoms at any given time. This allows for more Zn atoms to be ionized and dissolved into the solution per second.
Explanation:
Ill in the blank with the correct number to balance the equation: ___KClO3 → 2KCl 3O2. (Enter only a whole number. )
Numerical Anwer Expected!
Anwer for Blank 1:
Answers
Correct number to balance the equation: ___KClO3 → 2KCl 3O2 is "2".
We obtain KCl and oxygen gas from the breakdown of potassium chlorate (KClO3).
1.5 moles of O2 gas and one mole of KCl are produced from one mole of KClO3.
Therefore, the response will be:
KCL)3 - - > KCL + 3/2 O2
The entire equation will be multiplied by two in order to transform the fractional coefficient to a whole number.
2X [ KCLO3 - - > KCL + 3/2 O2 ]
A balanced equation will therefore be:
2KCLO3 - - > 2KCL + 3 O2
KClO3's coefficient is therefore "2".
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NaOH+ N2O3---> ___+____
Answers
Answer:
NaOH+ N2O3---> NaNO2 + H2O
acids are and can destroy your skin and bones
Answers
Answer:
This is true.
Explanation:
how many molecules are required to produce 15.8 moles of no2
Answers
✥ So, in 1.25 moles of NO2, you would have 1.25 moles of N and (2 x 1.25) 2.50 moles of O.
0.1 mole = Avogadro's number of particles (approx. 6.022x10^23 particles/mol)
So, #oxygen atoms = 2.50 mol x 6.022x10^23 atoms/mol
6.022x10^23 atoms/molOr, approximately 1.51x10^24 oxygen atoms.
Hope this answer helps you ✨
Substance to
be dissolves
less of it
Answers
Answer:
solute
Explanation:
How much heat is given off when you freeze 95.7 g of water?
Answers
Answer:
Hey kimalonzo59!
· Calculate specific heat as c = Q / (mΔT). In our example, it will be equal to c = -63,000 J / (5 kg * -3 K) = 4,200 J/ (kg·K). This is the typical heat capacity of water.
I hope this Helps, Have an Awesome Day!
~ Chloe Marcus ❤
Water freezes at 0° C. One gram of water when freezes release 333.55 J/g of energy. Therefore, 95.7 g of water releases 31920.73 J energy when freezing.
What is freezing point?Freezing point is the temperature at which a substance changes from its liquid state to solid state, where, these two states are in equilibrium. Freezing point of a substance depends on the molecular weight, bond type, temperature and pressure.
The energy released during the phase change from liquid to solid is called heat of fusion or fusion enthalpy. More specifically it is the energy required to fuse the molecules together to form their solid pack.
The heat of fusion of water is 333.55 J/g. Therefore, 1 g of water when freezes at 0° C it releases 333.55 J of energy. Thus, the amount of energy released when 95.7 g of water is freezed can be calculated as follows:
Heat of fusion = mass × heat fusion of 1 g of water
= 95.7 g × 333.55 J/g
= 31920.73 J
Therefore, 95.7 g of water releases 31920.73 J heat energy when freezing.
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In a solution, litmus is blue. The pH of the solution could be
1 10 2 2 3 3 4 4
Answers
Answer:
absotutately right
Explanation:
What is the pH color scale?
The pH scale runs from 0 to 14, with each number assigned a different color. At the bottom of the scale sits red, which represents the most acidic, and a dark blue at its opposite end represents 14 and alkalinity. In the middle zone, the pH scale becomes neutral
The pH of the solution could be 10. The basic solution has a pH value of more than 7.
What is pH?pH is a measure of acidity and basicity of aqueous solution.The range of pH goes from 0 - 14, with 7 being neutral.pH of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.pH is the measure of the relative amount of free hydrogen and hydroxyl ions in aqueous or other solutions.Litmus paper helps us qualitatively determine a substance as an acid or base. For any substance to be a base, blue litmus must remain blue.
The pH scale ranges from 0 to 14 and anything below 7.0 is acidic and anything above 7.0 is alkaline or basic.
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