Answer:
Check the explanation
Explanation:
1)
Atomic number of Se = 34
So, number of proton = 34
use:
charge = number of proton - number of electron
-2 = 34 - number of electron
number of electron = 36
number of neutron = mass number - atomic number
= 78 - 34
= 44
Answer:
44
34
36
2)
number of proton = mass number - number of neutron
= 65 - 36
= 29
29 is atomic number for Cu
use:
charge = number of proton - number of electron
+1 = 29 - number of electron
number of electron = 28
Answer:
Cu
29
28
3)
Atomic number is 36 for Kr
use:
charge = number of proton - number of electron
= 36 - 36
= 0
use:
mass number = number of proton + number of neutron
= 36 + 42
= 78
Answer:
Kr
78
0
Use the graph to determine which is greater, the heat of fusion or the heat of vaporization. Explain how you used the graph to determine that.
(The substance is water)
Answer:
mdjnibfziedosnninjd.zjcssksskskbsksbivfdlvdxkvfuwhiwhwonsk jsbudwuvsaeigdOhgrauvdslnzarm cxwmvakbxsabxwrifwzpgsdoh
ds
What is the concentration of a solution in which 0.99 g of KOH are dissolved in 500 mL?
Answer:
.00352mol/L
Explanation:
molarity (concentration) = number of moles / volume of solvent (in L)
M = .99g / 56.108g/mol / .5L
M = .0176mol / .5L
M = .00352mol/L
How many grams do 4.8 x 1026 atoms of silicon
weigh?
Answer in units of g.
It takes 300 N to move a box 10 meters in 10 seconds. How much power is
required?
A. 30,000 W
B. 100 W
C. 3,000 J
D. 300 W
Plz help
Answer:
Power, P = 300 W
Explanation:
We have,
Force acting on the box to take it is 300 N
It is moved to a distance of 10 m in 10 seconds
It is required to find the power required to move the box. The rate at which work is done is called power required by an object. It can be given by the formula as follows :
[tex]P=\dfrac{W}{t}\\\\P=\dfrac{Fd}{t}\\\\P=\dfrac{300\times 10}{10}\\\\P=300\ W[/tex]
So, the power required is 300 W.
How many moles
are equal to
4.11x1023
molecules of
CO2?
Explanation:
6.02×1023 culture atoms have a mass of 63.5g. 12.0g. c +23.0g O2__44.0g CO2.(12.0+16.0+16.0=44.0g).1 mol 1 mol. 1 mol number molecules weight
The number of molecules in one mole of carbon dioxide is 6.02 × 10²³. Therefore, the number of moles of carbon dioxide which contains 4.11 × 10²³ molecules is 0.68.
What is Avogadro number ?The number of atoms that constitutes one mole of a substance is called Avogadro number. It is equal to 6.02 × 10²³. Thus, one mole of every elements contains Avogadro number of atoms.
Similarly, one mole of a compound contains 6.02 × 10²³ number of molecules. Thus, one mole of carbon dioxide contains these much molecules.
Given the number of molecules of carbon dioxide = 4.11 × 10²³
Then, no.of moles = number of molecules/ Avogadro number.
no.of moles = 4.11 × 10²³ /6.022 × 10²³ = 0.68.
Therefore, the number of moles of CO₂ that contains 4.11 × 10²³ molecules is 0.68.
Find more on Avogadro number:
https://brainly.com/question/28834341
#SPJ5
The Earth's mantle is
A.
hotter than the crust but cooler than the core.
B.
hotter than both the crust and the core.
C.
cooler than both the crust and the core.
D.
cooler than the crust but hotter than the core.
Answer:
C. cooler than both the crust and the core
Explanation:
It is observed that at the mantle, temperatures range from estimatedly 200 °C (392 °F) around the upper boundary with the crust to approximately 4,000 °C (7,230 °F) at the core-mantle boundary.
So we can say the mantle is cooler than both the crust and the core.
Why did the Mt. Pinatubo eruption result in global temperatures dropping almost two degrees?
Answer:
In the case of Mount Pinatubo, the result was a measurable cooling of the Earth's surface for a period of almost two years. Because they scatter and absorb incoming sunlight, aerosol particles exert a cooling effect on the Earth's surface.
Explanation:
Temperature measures the average kinetic energy of particles of the substances. Therefore, the Mt. Pinatubo eruption result in global temperatures dropping almost two degrees.
What is temperature?Temperature is used to measure degree or intensity of heat of a particular substance. Temperature is measured by an instrument called thermometer.
Temperature can be measured in degree Celsius °c, Kelvin k or in Fahrenheit. Temperature is a physical quantity. Heat always flow from higher temperature source to lower temperature source.
We can convert these units of temperature into one another. The relationship between degree Celsius and Fahrenheit can be expressed as:
°C={5(°F-32)}÷9
The Mt. Pinatubo eruption result in global temperatures dropping almost two degrees because they scatter and absorb incoming sunlight, aerosol particles exert a cooling effect on the Earth's temperature.
Therefore, the Mt. Pinatubo eruption result in global temperatures dropping almost two degrees.
To know more about temperature, here:
https://brainly.com/question/13694966
#SPJ6
Which diagram correctly describes the changes that occur as a small piece of rock falls from space and hits the earth
Answer:
the motion of gravity
Explanation:
Answer:
its c
Explanation
advhuosijoklxcmnjdabsuhggggabciaciudeifweingivg eygerigsygfe97rsghisdcvhbsduigwiugfu9uigdgiurfgyisdgfsdgfegiygewifgsdygfewusgfuyesigf7wgfiesgfiusgdfies
How to make isopropyl alcohol
Answer:
.It is easily synthesized from the reaction of propylene with sulfuric acid, followed by hydrolysis. Isopropyl alcohol (2-propanol) is made by indirect hydration of propylene (CH2CHCH3).… In some cases the hydration of propylene is carried out in one step, using water and a catalyst at high pressure.
Hope it'll help!
stay safe:)
CH³C⁴HCOCH³ how many atoms of each element are in one molecule of 2-heptanone
Answer:
- 7 carbon atoms.
- 14 hydrogen atoms.
- 1 oxygen atom.
Explanation:
Hello,
In this case, for the given compound, heptanone, whose chemical formula is:
[tex]CH_3COCH_2CH_2CH_2CH_2CH_3[/tex]
We can write the molecular formula showing the present atoms of each element:
[tex]C_7H_{14}O[/tex]
In such a way we have:
- 7 carbon atoms.
- 14 hydrogen atoms.
- 1 oxygen atom.
Best regards.
Draw the structure of a compound with the molecular formula CgH1002 that exhibits the following spectral data.
(a) IR: 3005 cm-1, 1676 cm-1, 1603 cm-1
(b) H NMR: 2.6 ppm (singlet, I = 3H), 3.9 ppm (singlet, I = 3H), 6.9 ppm (doublet, I = 2H), 7.9 ppm (doublet, I = 2H)
(c) 13C NMR: 26.2, 55.4, 113.7, 130.3, 130.5, 163.5, 196.6 ppm ?
Answer:
The answer you are looking for is A
The largest contributed to water pollution is
Answer:
this si from google hope it helps
Explanation:
The Main Causes of Water Pollution in the U.S.
Runoff from Agricultural Operations. Agriculture represents one of the biggest sources of water pollution in the country. ...
Runoff and Nonpoint Source Pollution. ...
Industrial Activities. ...
Leakage from Underground Storage and Piping. ...
Leaking Sewers. ...
Vehicle Emissions. ...
Landfill Leakage. ...
Hazardous Waste.
Answer:
Runoff and Non-point Source Pollution.
Explanation:
it's caused by rainfall or snow-melt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters and ground and NPS is it's abbreviation.
a fertilizer manufacturer makes a batch of 20kg of ammonium nitrate. what mass of ammonia in kg, does the manufacturer need to start with?
Answer:
[tex]m_{NH_3}=4.25kgNH_3[/tex]
Explanation:
Hello,
In this case, for the production of ammonium nitrate we shall consider the following chemical reaction:
[tex]NH_3+HNO_3\rightarrow NH_4NO_3[/tex]
Hence, since the molar mass of ammonium nitrate is 80 g/mol and the molar mass of ammonia is 17 g/mol, we could compute the required mass of ammonia to produce 20 kg of ammonium nitrate by using kilo-based units:
[tex]m_{NH_3}=20kgNH_4NO_3*\frac{1kmol}{80kgNH_4NO_3}*\frac{1kmolNH_3}{1kmolNH_4NO_3}*\frac{17kgNH_3}{1kmolNH_3} \\\\m_{NH_3}=4.25kgNH_3[/tex]
Best regards.
Identifying the Body's Responses to
Quick
Check
Which type of response identifies a specific pathogen in the body?
A(n)
response
Answer:
Specific Immune Response
Explanation:
A specific immune response identifies the pathogen which then allows it to produce antibodies that protect against that SPECIFIC pathogen.
Answer:
immuneExplanation:
The glass of a lit 75-watt incandescent bulb is hotter to the touch than the glass of a 25-watt compact fluorescent (CFL) bulb that emits the same amount of light. What could be a reason for this
Question 17 In the Haber reaction, patented by German chemist Fritz Haber in 1908, dinitrogen gas combines with dihydrogen gas to produce gaseous ammonia. This reaction is now the first step taken to make most of the world's fertilizer. Suppose a chemical engineer studying a new catalyst for the Haber reaction finds that 786. liters per second of dinitrogen are consumed when the reaction is run at 222.°C and 0.35atm. Calculate the rate at which ammonia is being produced. Give your answer in kilograms per second. Round your answer to 2 significant digits.
Answer:
Explanation:
N₂ + 3H₂ = 2 NH₃
1 vol 2 vol
786 liters 1572 liters
786 liters of dinitrogen will result in the production of 1572 liters of ammonia
volume of ammonia V₁ = 1572 liters
temperature T₁ = 222 + 273 = 495 K
pressure = .35 atm
We shall find this volume at NTP
volume V₂ = ?
pressure = 1 atm
temperature T₂ = 273
[tex]\frac{P_1V_1}{T_1} =\frac{P_2V_2}{T_2}[/tex]
[tex]\frac{.35\times 1572}{495} =\frac{1\times V_2}{ 273 }[/tex]
[tex]V_2 =303.44[/tex] liter .
mol weight of ammonia = 17
At NTP mass of 22.4 liter of ammonia will have mass of 17 gm
mass of 303.44 liter of ammonia will be equal to (303.44 x 17) / 22.4 gm
= 230.28 gm
=.23 kg / sec .
Rate of production of ammonia = .23 kg /s .
What is the hydronium ion concentration of a 0.100 M acetic acid solution with Ka = 1.8 × 10-5? The equation for the dissociation of acetic acid is: CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq) What is the hydronium ion concentration of a 0.100 M acetic acid solution with Ka = 1.8 × 10-5? The equation for the dissociation of acetic acid is: CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq) 1.3 × 10-2 M 4.2 × 10-2 M 1.3 × 10-3 M 4.2 × 10-3 M
Answer:
1.3×10⁻³ M
Explanation:
Hello,
In this case, given the dissociation reaction of acetic acid:
[tex]CH_3CO_2H(aq) + H_2O(l) \rightleftharpoons H_3O^+(aq) + CH_3CO_2^-(aq)[/tex]
We can write the law of mass action for it:
[tex]Ka=\frac{[H_3O^+][CH_3CO_2^-]}{[CH_3CO_2H]}[/tex]
Of course, excluding the water as heterogeneous substances are not included. Then, in terms of the change [tex]x[/tex] due to the dissociation extent, we are able to rewrite it as shown below:
[tex]1.8x10^{-5}=\frac{x*x}{0.100-x}[/tex]
Thus, via the quadratic equation or solve, we obtain the following solutions:
[tex]x_1=-0.00135M\\x_2=0.00133M[/tex]
Obviously, the solution is 0.00133M which match with the hydronium concentration, thus, answer is: 1.3×10⁻³ M in scientific notation.
Regards.
Answer:
1.3×10^-3 M
Explanation:
Step 1:
Data obtained from the question:
Equilibrium constant (Ka) = 1.8×10^-5
Concentration of acetic acid, [CH3COOH] = 0.100 M
Concentration of hydronium ion, [H3O+] =..?
Step 2:
The balanced equation for the reaction.
CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq)
Step 3:
Determination of concentration of hydronium ion, [H3O+].
This can be obtained as follow:
Ka = [H3O+] [CH3CO2-] / [CH3CO2H]
Initial concentration:
[CH3COOH] = 0.100 M
[H3O+] = 0
[CH3CO2-] = 0
During reaction
[CH3COOH] = – y
[H3O+] = +y
[CH3CO2-] = +y
Equilibrium:
[CH3COOH] = 0.1 – y
[H3O+] = y
[CH3CO2-] = y
Ka = [H3O+] [CH3CO2-] / [CH3CO2H]
1.8×10^-5 = y × y / 0.1
Cross multiply
y^2 = 1.8×10^-5 x 0.1
Take the square root of both side
y = √(1.8×10^-5 x 0.1)
y = 1.3×10^-3 M
[H3O+] = y = 1.3×10^-3 M
Therefore, the concentration of the hydronium ion, [H3O+] is 1.3×10^-3 M
What is the molarity of sodium hydroxide solution made by combining 2.0 L of 0.60
NaOH With 495 mL 3.0 M NaOH? Assume the volumes of the two solutions to be additive___M
Answer:
[tex]M=1.1M[/tex]
Explanation:
Hello,
In this case, since we are mixing two NaOH solutions, the first step is to compute the total moles once the mixing is done, by using the volumes and concentrations of each solutions and subsequently adding them:
[tex]n_T=2.0L*0.60\frac{mol}{L}+495mL*\frac{1L}{1000mL}*3.0\frac{mol}{L}= 2.7molNaOH[/tex]
Next, we compute the total volume by adding the volume of each solution:
[tex]V_T=2.0L+495mL*\frac{1L}{1000mL}= 2.495L[/tex]
Finally, we compute the molarity of the resulting solution by the division between the total moles and the total volume:
[tex]M=\frac{2.7mol}{2.495L}\\ \\M=1.1M[/tex]
Best regards.
If you start with 64g of a radioactive element how many half-lives would occur before 8g remain?
Answer:
3 half-lives
Explanation:
The half-life is the time that it takes to a radioactive element to decay to half of its initial amount.
Let's suppose we start with 64 g of the radioactive element.
After 1 half-life, the mass of the element will be 32 g.After 2 half-lives, the mass of the element will be 16 g.After 3 half-lives, the mass of the element will be 8 g.A sample of gas at occupies 10m3 at a pressure of 120 kPa. If the volume of the sample is changed to 3m3, what is the new pressure of the gas?
Answer:
400 kPa
Explanation:
Please see the step-by-step solution in the picture attached below.
Hope this answer can help you. Have a nice day!
Answer:
400 kPa
The answer is right since its from ck12
4. A taxi ride costs $5 plus .75 cents per mile. If I
ride for 120 miles, how much will be charged?
Answer:
$95
Explanation:
.75 x 120 = 90
90+5 = 95
Which picture shows how the moon from earth when it’s in the position
Explanation:
This picture shows how the moon from earth when it is in position
what is the reaction?
Answer:
A chemical reaction is a process in which one or more substances, also called reactants, are converted to one or more different substances, known as products. ... A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Explanation:
Hopefully this is what you needed
Gaseous butane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 42. g of butane is mixed with 150. g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Round your answer to significant digits.
Answer:
127 grams of carbon dioxide
Explanation:
We need to determine the chemical equation first. Butane has a chemical formula of [tex]C_4H_{10}[/tex], oxygen is [tex]O_2[/tex], carbon dioxide is [tex]CO_2[/tex], and water is [tex]H_2O[/tex]. The reactants are butane and oxygen and the products are carbon dioxide and water. So we write:
[tex]C_4H_{10}+O_2[/tex] ⇒ [tex]CO_2+H_2O[/tex]
But remember! We need to balance this. Currently, there are 4 carbon atoms (C), 10 hydrogen atoms (H), and 2 oxygen atoms (O) on the left, while there are 1 carbon atom (C), 2 hydrogen atoms (H), and 3 oxygen atoms (O) on the right. Let's place a coefficient of 4 in front of the carbon dioxide and a coefficient of 5 on the water, so that we have equal numbers of carbon and hydrogen atoms on each side:
[tex]C_4H_{10}+O_2[/tex] ⇒ [tex]4CO_2+5H_2O[/tex]
However, we need to ensure that there are equal numbers of O atoms, as well. On the left, we have 2 and on the right we have 13, so let's put a coefficient of 6.5 on the oxygen:
[tex]C_4H_{10}+6.5O_2[/tex] ⇒ [tex]4CO_2+5H_2O[/tex]
Finally, multiply everything by 2 to get whole number coefficients:
[tex]2C_4H_{10}+13O_2[/tex] ⇒ [tex]8CO_2+10H_2O[/tex]
Ah, now we can actually get to the problem!
We need to determine the limiting reactant, so let's convert the 42 g of butane and 150 g of oxygen into moles of any product, say, carbon dioxide. To convert to moles, we need to find the molar mass of each compound.
The molar mass of butane is 4 * 12.01 + 10 * 1.01 = 58.14 g/mol, while the molar mass of oxygen is 2 * 16 = 32 g/mol. We can now set up the equations:
[tex]42 gC_4H_{10}*\frac{1molC_4H_{10}}{58.14gC_4H_{10}} *\frac{8molCO_2}{2molC_4H_{10}} =2.8896molCO_2[/tex]
[tex]150 gO_2*\frac{1molO_2}{32gO_2} *\frac{8molCO_2}{13molO_2} =2.8846molCO_2[/tex]
Clearly, we see that 2.8846 < 2.8896, which means that oxygen is the limiting reactant. In other words, the most products can be made when the oxygen is all used up.
Now let's finally convert moles of carbon dioxide into grams by multiplying by its molar mass, which is 12.01 + 2 * 16 = 44.01 g/mol:
[tex]2.8846molCO_2*\frac{44.01gCO_2}{1molCO_2} =127gCO_2[/tex]
Notice that we have 3 significant figures because we had 3 significant figures at the start with 150. grams of oxygen.
~ an aesthetics lover
In a titration, 100 mL of 0.026 M HCl (aq) is neutralized by 13 mL of KOH(aq). Calculate the molarity of KOH (aq).
Answer:
0.2M
Explanation:
Step 1:
Data obtained from the question.
Volume of acid (Va) = 100mL
Molarity of the acid (Ma) = 0.026 M
Volume of base (Vb) = 13mL
Molarity of the base (Mb) =..?
Step 2:
The balanced equation for the reaction. This is given below:
HCl + KOH —> KCl + H2O
From the balanced equation above,
The mole ratio of the acid (nA) = 1
The mole ratio of the base (nB) = 1
Step 3:
Determination of the molarity of the base, KOH. This can be obtained as follow:
MaVa/MbVb = nA/nB
0.026 x100 / Mb x 13 = 1
Cross multiply to express in linear form
Mb x 13 = 0.026 x 100
Divide both side by 13
Mb = 0.026 x 100 / 13
Mb = 0.2M
Therefore, the molarity of the base, KOH is 0.2M
Answer:
0.2M
Explanation:
KOH(aq) + HCl(aq) ⇒ KCl(aq) + H2O(l)
We express the moles of analyte (HCl) and titrant based (KOH) on their molar concentration:
M1 * V1 = M2 * V2
The molarity of the solution is calculated with the following equation:
M2 = V1 x M1 / V2
Where:
V2 = valued sample volume
V1 = volume of titrant consumed (measured with the burette)
M1 = concentration of titrant solution
M2 = concentration of sample
M2 = 100mL * 0.026M / 13mL = 0.2M
The change in entropy, ΔS∘rxn , is related to the the change in the number of moles of gas molecules, Δngas . Determine the change in the moles of gas for each of the reactions and decide if the entropy increases, decreases, or has little or no change. A. 2H2(g)+O2(g) ⟶ 2H2O(l) Δngas= mol The entropy, ΔS∘rxn , increases. decreases. has little or no change.
Explanation:
Entropy of a reaction ΔS∘rxn is the degree of disoderliness in a system. Gases generally have a higher degree of disorder compared to liquids. Hence for the reaction 2H2(g)+O2(g) ⟶ 2H2O(l), the entropy decreases sice the reactants are in the gaseous state and the products is in the liquid state of matter
If an insufficient amount of liquid unknown had been used, how would this have effected the value of the experimental molar mass
Answer:
Actual yield reduces the more.
Explanation:
An actual yield of the course of a chemical reaction is the mass of a product actually obtained from the reaction.
In practice you see it and It is usually less than the theoretical yield.
Various reasons may come up to explain this away but here is one:
• incomplete reactions, simply put here some of the reactants do not react to form the product.
The same applies in the question about the actual yield will reduce significantly in molar mass now that insufficient amount of reagent are used.
methane Express your answer as a condensed structural formula omitting all bonds (e.g CH3CH2CH3). nothing Request Answer Part B ethane Express your answer as a condensed structural formula omitting all bonds (e.g CH3CH2CH3). nothing Request Answer Part C pentane Express your answer as a condensed structural formula omitting all bonds (e.g CH3CH2CH3). nothing Request Answer Part D cyclopropane Draw the molecule on the canvas by choosing buttons from the Tools (for bonds), Atoms, and Advanced Template toolbars. Include all hydrogen atoms.
Answer:
a
The condensed structural formula for methane is
[tex]CH_4[/tex]
b
The condensed structural formula for ethane is
[tex]CH_3 CH_3[/tex]
c
The condensed structural formula for pentane is
[tex]CH_2(CH_2)_3CH_3[/tex]
d
The diagram for the structural formula for cyclopropane is shown on the first uploaded image
Explanation:
At constant pressure, what generally happens to the solubility of solids and gases when the temperature of a solution is increased?
A. The solubility of solids and gases increases.
B. The solubility of solids and gases decreases.
C. The solubility of solids increases, and the solubility of gases decreases.
D. The solubility of solids decreases, and the solubility of gases increases.
Answer:
C)
Explanation:
JUST DID IT
Answer:
A D E
Explanation:
just did it
2. What happens to the pH when you add more H+ ions to a solution that has no buffers?
