Answer:
145,000 meters
Explanation:
1 kilometer = 1000 meter
145 kilometer = 145 times 1000 meters
so:
145 × 1000 = 145,000 meters
A cobalt atom has 27 protons. What number of neutrons would make a cobaltatom most stable?OA. 54OB. 27OC. 25OD. 32
Answer:
D. 32.
Explanation:
Remember the formula of atomic mass:
[tex]atomic\text{ mass=atomic number+\# neutrons.}[/tex]If you go to see the periodic table, you can note that the atomic mass of cobalt is 58.9 amu rounded to 59 amu. Let's solve for '# neutrons' and replace the atomic mass (59) and the atomic number (27) (remember that the number of protons is the same that the atomic number), like this:
[tex]\begin{gathered} #\text{ neutrons=atomic mass-atomic number,} \\ #\text{ neutrons=59-27,} \\ #\text{ neutrons=32.} \end{gathered}[/tex]The answer would be that the number of neutrons to make a cobalt atom most stable is D. 32.
Carbon dioxide (co2) is a gaseous compound. calculate the percent composition of this compound. answer using one decimal place. what is the percent by mass of carbon? % what is the percent by mass of oxygen? %
The percent composition of carbon dioxide is as follows: 27.3% carbon, 72.7% oxygen.
To calculate the percent composition of the compound, we can assume that we have one mol of carbon dioxide. The molar mass of carbon dioxide is 44 g/mol.
Based on the molecular formula of carbon dioxide (CO₂), we can say that 1 mol of CO₂ contains 1 mol of carbon and two moles of oxygen.
The molar mass of carbon is 12 g/mol, and we can calculate its percent by mass by dividing the mass of carbon in carbon dioxide by the mass of carbon dioxide and multiplying the result by 100%:
%C = 100% * 12 g/mol / 44 g/mol
%C = 27.3%
Because carbon dioxide is made of only carbon and oxygen, we can the oxygen percent by mass by simply subtracting the carbon percent by mass from 100%:
%O = 100% - %C
%O = 100% - 27.3%
%O = 72.7%
You can learn more about percent composition here:
brainly.com/question/17505281
#SPJ4
Which of these is an example of a physical change?
à rusting metal
& browning fruit
burning wood
melting ice
Answer:
The correct answer is Water boiling. Examples of physical change are freezing of water, boiling of water, melting of wax, etc. Examples of chemical change are digestion of food, burning of paper, rusting of metal, silver tarnishing, etc.
The argon fluoride (arf) laser used in some refractive eye surgeries emits electromagnetic radiation of 193.3 nm wavelength. what is the frequency of the arf laser's radiation? what is the energy of a single quantum of the radiation?
The frequency of the radiation is 1.6 * 10^15 Hz while its energy is 1.056 * 10^-18 J
What is the frequency?Recall that the electromagnetic radiation is commonly called light. All the members of the electromagnetic spectrum are known to have the speed of light which is 3 * 10^8 m/s. The first task that we have is to obtain the frequency of the electromagnetic wave since we have the wavelength of the wave we seek.
Given that;
frequency = Speed of light/ wavelength
Frequency = 3 * 10^8 m/s/193.3 * 10^-9 m
Frequency = 1.6 * 10^15 Hz
Next we need to obtain the energy of the radiation and we have to do that from;
E = hf
E = energy of the photon
h = Planks constant
f = frequency of the photon
E = 6.6 * 10^-34 * 1.6 * 10^15 Hz
E = 1.056 * 10^-18 J
Learn more about electromagnetic radiation:https://brainly.com/question/10759891
#SPJ1
Write the ionic equation
Ba(NO3)₂ (aq) + Na₂S04 (aq).
what is a type of energy that powers a cell phone?
Please help me with this Chemistry problem..
11) In the reaction 2SO2(g) + O2(g) → 2SO3(g), how many moles of O2 are needed to produce 8.46 moles of SO3?
To solve this question, we need to look at the stoichiometric ratio between oxygen and SO₃, which in this case is 1:2
So 1 mole of O2 produces 2 moles of SO3.
Now we can use the rule of 3:
1 mole O2 --- 2 mole SO3
x mole O2 --- 8.46 moles SO3
2x = 1 x 8.46
x = 8.46/2
x = 4.23
Answer: 4.23 moles of O2
Why are low pressure systems associated with high temperatures?
Low pressure systems associated with high temperatures because warm air rises :)
A particular compound has an enthalpy of vaporization of 28900 J/mol. At 278 K it has a vapor pressure of 103 mmHg. What is its vapor pressure at 309 K? (R = 8.31 J/(K· mol))a. 29.4mmhgb. 99.5mmhgc. 107mmhgd. 194mmhge. 361mmhg
Answer:
[tex]E\text{ : 361 mmHg}[/tex]Explanation:
Here, we want to get the vapour pressure of the compound at the given temperature
We can use the Clausius-Clapeyron equation for this
Mathematically, we have this as:
[tex]\ln (\frac{P_1}{P_2})\text{ = -}\frac{\Delta H}{R}(\frac{1}{T_1}-\frac{1}{T_2})[/tex]So,let us identify the values:
P1 = 103 mmHg
P2 = ?
ΔH = 28,900
R = 8.31
T1 = 278 K
T2 = 309 K
We now proceed to substitute these values into the equation above as follows:
[tex]\begin{gathered} \ln (\frac{103}{P_2})\text{ = -}\frac{28900}{8.31}(\frac{1}{278}-\frac{1}{309}) \\ \\ \ln (\frac{103}{P_2})\text{ = -3477.74 (}\frac{31}{85902}) \\ \\ \ln (\frac{103}{P_2})\text{ = -1.255} \\ \\ e^{-1.255}\text{ = }\frac{103}{P_2} \\ P_2\text{ = 361 mmHg} \end{gathered}[/tex]the law of says, “Energy is neithet created nor destroyed,only transferred or transformed
Answer:
this is Daltons atomic theory
Answer:
this means that energy cannot be created or destroyed
Explanation:
it is because energy can change into many different forms such as heat or nuclear during chemical reactions
QUICK QUESTION...
What is the best method to use in extracting orange sugar from a whole orange
What is it you are making exactly? It is going to be for a recipe of some sort, like a beverage or food? If you could sort of expand on what the purpose is for, I think I may be able to help you find the best method for the extraction.
Which statement correctly compares the weight and the mass of an object?
Answer:
Its weight changes based on location, but its mass stays the same.
Explanation:
See attached worksheet.
Calculate the number of oxygen atoms is 0.5
Answer:
Therefore the number of oxygen atoms will be. 033 × 10 23 atoms.
Which of the following diagrams has correctly shaded the metals in blue?
1) Groups of elements in the periodic table.
Metals are located in the middle and left side of the periodic table.
The second picture has correctly shaded the metals.
.
this tank has been set up with cold water on one side and warm water on the other. when the divider is removed and the two water samples are allowed to mix, what is most likely to happen?
Since warm water has more energy than cold water, its molecules move more quickly than those in cold water. Gradually both the water will have same temperature according to Principle of calorimetry.
Heat lost by the hot body = heat gained by the cold body
What is principle of calorimetry?
In a calorimeter, two different types of matter are in contact with one another, ideally a liquid and a solid. Both bodies are also at various temperatures. A higher-temperature object can transfer heat energy to a lower-temperature object thanks to this setup.
Heat transfer does not stop, nevertheless, until there is a state of thermal equilibrium between the bodies. The "rule of conservation of energy," which is represented by the principle of calorimetry, states that the total amount of heat absorbed by the cold object and the total amount of heat released by the hot object are equal.
Since warm water has more energy than cold water, its molecules move more quickly than those in cold water. Gradually both the water will have same temperature
To know about principle of calorimetry from the link
https://brainly.in/question/4370390
#SPJ4
Explain FULLY what this symbol means/can tell you ( be sure to talk about numbers of protons, neutrons, and electrons.
Chlorine has 17 protons, 17 electrons and 18 neutrons. The atomic number is 17 and the mass number is 35.
Explanations:The given element is Chlorine with an atomic number of 17 and a mass number of 35. The subscript serves as the atomic number while the superscript is the mass number.
The proton number is equal to the atomic number and electron number of a chlorine atom. Therefore;
Proton number = electron number = 17
For the neutron number
Neutron number is the difference between the mass number and the proton number;
Neutron number = Mass number - Proton number
Neutron number = 35 - 17 =18
Hence there are 18 neutron numbers in a chlorine atom
which statement is true about about these two solutions, if you compare them to each other: 1m of 100 ml kcl (aq) solution and 1m of 100 ml mgcl2(aq) solution? group of answer choices the mgcl2 solution has a higher amounts of ions. all of correct. the kcl solution has lower conductivity values. the kcl solution has a fewer amount of ions. the mgcl2 solution has higher conductivity values.
All are correct about two solutions of KCl and [tex] MgCl_{2}[/tex].
Both the compounds KCl and [tex] MgCl_{2}[/tex] are ionic compounds. So, they easily dissociate on contact water with constituent ions. KCl dissociates into one cation [tex] {K}^{+} [/tex] and one anion [tex] {Cl}^{-} [/tex]. [tex] MgCl_{2}[/tex] dissociates into one cation [tex] {Mg}^{2+} [/tex] and two anions [tex] {Cl}^{-} [/tex].
So, the KCl solution produces two ions while the [tex] MgCl_{2}[/tex] solution produces three ions. More number of ions means higher amount of charge can be carried at a time and hence higher conductivity will be seen. Likewise, less number of ions in the solution indicates less capacity to conduct electricity. Thus, [tex] MgCl_{2}[/tex] has higher amount of ions thus higher conductivity. Similarly, KCl has lesser amount of ions in the solution thus it has lower conductivity.
Learn more about ionic dissociation -
https://brainly.com/question/14761540
#SPJ4
in the laboratory, a student adds 44.2 ml of water to 20.6 ml of a 0.652 m hydroiodic acid solution. what is the concentration of the diluted solution? assume the volumes are additive.
The concentration of diluted solution is 0.2 M.
The concentration and volume are related by the formula - [tex] M_{1}[/tex] [tex] V_{1}[/tex] = [tex] M_{2}[/tex] [tex] V_{2}[/tex], where [tex] M_{1}[/tex] and [tex] M_{2}[/tex] are initial and final concentration. [tex] V_{1}[/tex] and [tex] V_{2}[/tex] are initial and final volumes.
Keep the values in relation to find the concentration of final diluted solution.
0.652 × 20.6 = [tex] M_{2}[/tex] × (44.2 + 20.6)
Performing addition on Right Hand Side
0.652 × 20.6 = [tex] M_{2}[/tex] × 64.8
Performing multiplication and division
[tex] M_{2}[/tex] = 13.43÷64.8
[tex] M_{2}[/tex] = 0.2 M
Thus, the diluted solution is 0.2 M.
Learn more about concentration and volume -
https://brainly.com/question/26756988
#SPJ4
which is a difference between butyne and cyclobutyne? group of answer choices cyclobutyne does not exist. butyne's multiple bond is interior, cyclobutyne is not between interior carbons. cyclobutyne burns much hotter than butyne because of the greater unsaturation. both b and c are differences between the molecules.
Cyclobutyne does not exist. A hydrocarbon molecule called cyclobutyne has a triple bond inside of a ring with four carbon atoms.
Due to its high ring strain, this cycloalkyne is extremely unstable and hasn't been isolated in its purest form.
What is butyne ?Organic compound butyne has the chemical formula HC2CH2CH3. It is a flammable, colourless gas. 1-Butyne takes part in processes that are common for terminal alkynes, such as hydrogenation, condensation with formaldehyde, and alkyne metathesis.
Due of its extremely low torsional barrier and the difficulty in identifying it using high-resolution infrared spectroscopy, 2-butyne is of interest to physical chemists.
Cycloalkenes include cyclobutene. It offers potential for research but no immediate applications. It is an effortlessly condensible colourless gas. In a contemporary synthesis, cyclobutanol is dehydrated twice. The ammonium salt OH was first thermolyzed to create the chemical.
Cycloalkanes are monocyclic saturated hydrocarbons in organic chemistry. To put it another way, all of the carbon-carbon bonds in a cycloalkane's structure are single and it only contains hydrogen and carbon atoms grouped in a configuration with a single ring.
When a cycloalkane has more than 20 carbon atoms, it is often referred to as a cycloparaffin. The isomers of alkenes make up all cycloalkanes.
To learn more about about butyne refer :
https://brainly.com/question/1621746
#SPJ4
Nothing like cyclobutyne exists. Cyclobutyne, a hydrocarbon molecule, features a triple bond inside of a ring made up of four carbon atoms. This cycloalkyne hasn't been isolated in its purest form because of its high ring strain, which makes it very unstable.
Describe butyne.?Butyne is an organic molecule with the formula HC2CH2CH3, according to chemistry. It is a flammable, colorless gas. 1-Butyne takes part in processes that are typical for terminal alkynes, such as hydrogenation, condensation with formaldehyde, and alkyne metathesis.
Because of its very low torsional barrier and the difficulty in locating it using high-resolution infrared spectroscopy, 2-butyne is of interest to physical chemists.
One of the cycloalkenes is cyclobutene. Although it might be studied, there are currently no applications in real life. It is an easily condensable colorless gas. In a contemporary synthesis, cyclobutanol passes through two stages of dehydration. The ammonium salt OH was first thermolyzed to create the chemical.
In organic chemistry, cycloalkanes are monocyclic saturated hydrocarbons. To put it another way, a cycloalkane has single carbon-carbon bonds throughout its whole structure.
To learn more about 'butyne' refer to
https://brainly.ph/question/10477335
#SPJ4
a buffer contains equal amounts of a weak acid and conjugate base and has a ph of 5.25. how will the concentration of conjugate base in the buffer change after the addition of a small amount of strong base?
The concentration of conjugate base in the buffer change after the addition of a small amount of strong base The concentration of conjugate base will increase. HA+BOH ⇒ H2O +AB
Buffer capacity refers to the amount of added acid or base that can be neutralized by a buffer. This is determined by the concentration of the conjugate acid and conjugate base. As these concentrations increase, the buffering capacity increases. A buffer is a solution that can withstand changes in pH due to the addition of acidic or basic components.
Can neutralize small amounts of added acids or bases and keep the pH of the solution relatively stable. When a strong base is added to a buffer the hydroxide ions are consumed by the weak acid, forming water, and consumed by the weak conjugate base of the acid. The number of weak acids decreases and the number of conjugate bases increases.
Learn more about The concentration here:-https://brainly.com/question/17206790
#SPJ4
In two to three sentences, explain the importance of the following in a nuclear reactor:
control rods
containment structure
a moderator
The importance of the following below in a nuclear reactor are:
Control rods - Reaction maintenance.Containment structure - Protection for the environment.Moderator - slows electrons down.What is a Nuclear reactor?This is referred to as the device which is used to start up and control a fission or fusion nuclear chain reaction or nuclear fusion reactions.
The control rod is responsible for the absorption of neutrons so that the nuclear chain reaction taking place within the reactor core can be slowed or stopped. The containment structure help to prevent rays from getting into the environment thereby serving as a protective factor.
The moderator helps to slow down the speed of neutrons especially in those who have a very high speed thereby making it the correct choice.
Read more about Nuclear reactor here https://brainly.com/question/3665055
#SPJ1
why we can't add an ion [ H+ ] to [ H3O+ ] ???
tysmmmm
The hydrogen ion, H⁺ cannot be added to a hydronium ion, H₃O⁺ , because the hydronium ion already contains a hydrogen ion.
What are the ions, H⁺ and H₃O⁺?The ions H⁺ and H₃O⁺ are the hydrogen ion and the hydronium ion respectively.
The hydrogen ion, H⁺ is formed when a hydrogen atom loses an electron. The hydrogen ion is known as a proton.
It is produced by acids when they dissociate in solution.
The hydronium ion, H₃O⁺ is formed when a water molecule combines with a hydrogen ion.
Because a hydrogen ion cannot exist on its own in aqueous solutions, the hydronium ion is the proper representation of the hydrogen ion in aqueous solutions.
Hence, the hydrogen ion H⁺, and the hydronium ion, H₃O⁺ are used interchangeably to represent acids in solution.
Learn more about hydronium ions at: https://brainly.com/question/27586088
#SPJ1
Consider the hydrate calcium chloride dihydrate: cacl2 · 2h2o. how many hydrogen atoms are in the compound?
Consider the hydrate calcium chloride dihydrate hydrogen atoms are in the compound are four
Hydrate calcium chloride dihydrate is the excellent water soluble crystalline calcium sources used compatible with chloride and chloride compounds can conduct electricity when fused or dissolved in water and here given compound is CaCl₂ × 2H₂O
So in that compound the hydrogen atom are four because this compound or this equation is balanced so in that compound four hydrogen atom are present
Know more about hydrogen
https://brainly.com/question/13954550
#SPJ1
Answer:
4
Explanation:
Choose the isotope in each pair that can be used in radiometric dating. Then, explain how you made your selection. (Hint: you'll need a version of the periodic table of elements that includes each element's atomic weight.)
Potassium-41, Potassium-39
Chlorine-35, Chlorine-36
Iodine-129, Iodine-127
The two isotopes that can be used for the process of dating are Potassium-41, Potassium-39.
What is radiometric dating?The term radiometric dating has to do with the process by which the age of a rock can be discovered. We know that rocks that are around us have been around for very many years. As a matter of fact, there are some of the rocks that could be regarded as being as old as the earth could be in itself.
We have to note that one of things that could be regarded as important in the use of any isotope for dating is that isotope must have a long half life. The fact that the isotope has a long half life means that it is able to remain long enough for it to be used in the study of a substance.
We know that most of the rocks are composed of potassium as part of the components of the rock. In that case, if a dating technique would involve the potassium atom then it is likely to be a successful one as it were.
Learn more about radiometric dating:https://brainly.com/question/14799339
#SPJ1
a compound is found to contain 13.65 % carbon and 86.35 % fluorine by mass. what is the empirical formula for this compound? to answer the question, enter the elements in the order presented above.
Answer:
[tex]CF_{4}[/tex]
Explanation:
See attached worksheet
Which element has 2 valence electrons and 5 energy levels?
Answer:
its Boron i hope this helped.
Explanation:
you need to prepare 1 l of the acetic acid/acetate buffer. you decided to mix 300 ml of 0.45 m acetic acid acid and 100 ml of 0.65 m naoh plus water to a final volume of one liter. the pka of acetic acid is 4.75. 1. calculate the ph of your buffer solution. 2. naoh is not the conjugate base to acetic acid. explain why you can use naoh to make an effective acetate buffer.
The pH of buffer solution is 4.72.
1) Molarity of acetic acid = 0.45 M
The volume of acetic acid = 300 ml
Molarity of NaOH = 0.65 M
Volume of NaOH = 100 ml
An acidic buffer solution is calculated by using Henderson's equation:
pH = pKa + ㏒[salt] / [acid]
where pKa = 4.75
pH = 4.75 + ㏒[0.065M] / [0.07M]
pH = 4.75 + ㏒(0.929)
pH = 4.75 - 0.03
pH = 4.72
Therefore, the pH of the buffer solution is 4.72.
2) NaOH is not the conjugate base to acetic acid. As we know NaOH is a strong base and acetic acid is a weak acid. Thus, an acid-base reaction occurs between acetic acid and NaOH, thus forming CH₃COONa, which is the conjugate base of acetic acid.
Acidic buffer solution is formed by mixing of weak acid and its conjugate salt of strong base. Thus, NaOH acts as limiting reactant and only CH₃COOH and CH₃COONa is present in solution. Thus, CH₃COOH is weak acid and CH₃COONa is its conjugate salt of strong base forms buffer solution. In the reaction of NaOH and CH₃COOH, NaOH gets completely reacted and forms CH₃COONa. Thus, NaOH is added to make an effective acetate buffer.
To learn more about pH and buffer solution, visit: https://brainly.com/question/13423298
#SPJ4
what statements are always true about limiting reactants? select one or more: there will be an excess of other reactants at the end of the reaction. the limiting reactant is completely used up in the reaction. the limiting reactant is always the same for a given reaction. the limiting reactant dictates the amount of product. the limiting reactant has a lower mass than other reactants.
There will be an excess of other reactants at the end of the reaction are always true about limiting reactants.
Why do reactants have a limiting effect?The reagent (compound or element) that must be completely consumed in a chemical reaction is known as the limiting reactant. Because there is no more reactant, limiting reactant is also what stops a reaction from continuing.
Limiting factors in stoichiometry are the reagents or reactants that are used by a chemical reaction before other reagents. The reactant or reagent having the lowest supply in relation to its required ratio compared to other reactants within the system is the limiting factor.
A chemical reactant known as a limiting reagent restricts the amount of product that may be produced. Based on the reagents (reactants) at hand, the limiting reagent produces the least amount of product. The theoretical yield refers to this minimum product yield.
Learn more about limiting reactant refer
https://brainly.com/question/14222359
#SPJ14
Which of the following statements about thermal energy is true? As you hold a cup of hot water, the heat moves to your hand. As you hold a cup of cold milk, your hand cools the milk. As you hold a cup of hot water your hands cool the water. As you hold a glass of cold milk, the cold travels to your hand.
Answer: As you hold cold milk.... travels to your hand
Explanation:
Cold and hot are compared to your own body temperature. So yeah that's kind of off topic but yeah. Anyways, to the explanation: so, this can be tested--obviously--by literally doing what the statement says. after you are done holding the milk, you will notice your hand is cold. This is because the milk is cooling down your hand to balance out the temperatures.