Answer:
216.5 amu
Explanation:
Step 1: Given data
Mass of isotope ²¹⁵X (m²¹⁵X): 215 amuAbundance of isotope ²¹⁵X (ab²¹⁵X): 25%Mass of isotope ²¹⁷X (m²¹⁷X): 217 amuAbundance of isotope ²¹⁷X (ab²¹⁷X): 75%Step 2: Calculate the average atomic mass for the element
When an element has 2 or more isotopes, we calculate the average atomic mass (am) using the following expression.
am = ∑ mi × abi / 100%
where,
mi: mass of each isotope
abi: abundance of each isotope
am = (m²¹⁵X × ab²¹⁵X + m²¹⁷X × ab²¹⁷X) / 100%
am = (215 amu × 25% + 217 amu × 75%) / 100% = 216.5 amu
In general chemicals enter Ecosystems through which two spears
Answer:
biosphere and lithosphere
Explanation:
The biosphere is described as the zone of life on Earth. It is a sum of all ecosystems. The biosphere is composed of living organisms and non-living factors.
The lithosphere is the outer part of the Earth such that this part is rocky. The lithosphere is made up of the brittle crust.
In general, chemicals enter Ecosystems through the biosphere and lithosphere.
When rocks slowly crumble due to rain, ice, and wind and
erode away, these processes form what?
How many electrons must Aluminum lose or gain to obtain a noble gas
electron configuration? *
Answer:
3 electrons
Explanation:
aluminum : [Ne]3s23p1 [ N e ] 3 s 2 3 p 1 . It loses 3 electrons from 3s and 3p orbitals and attains the noble gas configuration of Neon.
Answer:
it loses 3 electrons from 3s and 3p orbitals and attains the noble gas configuration of Neon.
Explanation:
the guy on top beat me to it gg
Timmy pushes off of the pool wall with a force of 2300 N and accelerates at 15 m/
what is mass? (ignore water resistance)
use one decimal place in your answer
Please help!
Answer:
Mass = 153.33 Kg
Explanation:
Given:
Force = 2,300 N
Acceleration = 15 m/s²
Find:
Mass
Computation:
Mass = Force / Acceleration
Mass = 2,300 / 15
Mass = 153.33 Kg
HELP I HAVE 3 MINUTES LEFT
Answer: kinetic energy
Answer:
Kinetic Energy.
Explanation:
All these "forces" rely on specific motion.
Hello! Please help :((
Find the distance from point B to point C. Enter as a decimal rounded to the nearest tenth. А 61° 5.7 mi B С BC = [?] mi Enter
Answer:
BC = 10.28 ≈ 10.3 mi to the nearest tenth
Explanation:
Using the trigonometry rules; SOH CAH TOA,
TOA would be more suitable in this question.
Tan ∅ = Opposite / Adjacent
Tan 61 = BC / AB
1.8040 = BC / 5.7
BC = 5.7 * 1.8040
BC = 10.28 ≈ 10.3 mi
the answer is 10.3, i already rounded it.
Which of Newton's Three Laws is BEST described by the following statement: A ball dropped from the 10th story of a hotel had more force than when the same ball was dropped from the 5th story of the same hotel
Answer:
I believe the answer is Newton's Second Law
Explanation:
Newton's Second Law states that the acceleration of an object will count on how much mass and the amount of force that is applied.
The bowling ball was dropped from the 10th story window and had more force than when the ball was dropped from the 5th story window because the 10th story window gave the bowling ball more acceleration.
Convert the volume, nm^3, to liters (L) by using the box dimensions of 4nm x 8.75nm x 10nm. Use the conversion factor of 1 L = 1 dm^3. Do not convert directly from nm^3 to dm^3
Answer:
[tex]V=3.50x10^{-22}L[/tex]
Explanation:
Hello there!
In this case, given the dimensions of the box, we first compute the volume by multiplying each side:
[tex]V=4nm*8.75nm*10nm=350nm^3[/tex]
Next, we apply the following conversion factor in order to obtain the corresponding liters:
[tex]V=350nm^3*(\frac{1m}{10^9nm} )^3*\frac{1000L}{1m^3} \\\\V=350nm^3*\frac{1m^3}{10^{27}nm^3} *\frac{1000L}{1m^3}\\\\V=3.50x10^{-22}L[/tex]
Best regards!
1.
Use the Rydberg equation to calculate the energy (in J) and then find the wavelength
in (nm) for the following transitions.
-18
AE = 2.179x10
a.
3-2.
Answer:
Approximately [tex]3.03\times 10^{-19}\; \rm J[/tex], which corresponds to a wavelength of approximately [tex]6.56 \times 10^{2}\; \rm nm[/tex] in vacuum.
Explanation:
When the electron of a hydrogen atom transits from energy level [tex]n_1[/tex] to [tex]n_2[/tex], the energy change would be:
[tex]\displaystyle \Delta E \approx 2.179 \times 10^{-18}\; {\rm J} \, \left(\frac{1}{{(n_1)}^{2}} - \frac{1}{{(n_2)}^{2}}\right)[/tex].
For the transition from [tex]n_1 =3[/tex] to [tex]n_2 = 2[/tex]:
[tex]\begin{aligned}\Delta E &\approx 2.179 \times 10^{-18}\; {\rm J} \, \left(\frac{1}{{(n_1)}^{2}} - \frac{1}{{(n_2)}^{2}}\right)\\ &= 2.179 \times 10^{-18}\; {\rm J} \, \left(\frac{1}{{3}^{2}} - \frac{1}{{2}^{2}}\right) \\ &\approx -3.02639 \times 10^{-19} \; \rm J \\ &\approx -3.03\times 10^{-19}\; \rm J\end{aligned}[/tex].
The value of [tex]\Delta E[/tex] is negative because energy is released during this transition.
Look up Planck's Constant (for finding frequency from energy) and the speed of light in vacuum (for finding wavelength from frequency.)
Planck's Constant: [tex]h \approx 6.62607 \times 10^{-34} \; \rm J \cdot s^{-1}[/tex].Speed of light in vacuum: [tex]c \approx 2.99792 \times 10^{8}\; \rm m \cdot s^{-1}[/tex].Calculate the frequency [tex]f[/tex] of photons from this transition using the Planck-Einstein relation:
[tex]E = h \cdot f[/tex].
Therefore:
[tex]\begin{aligned}f &= \frac{E}{h}\end{aligned}[/tex].
Calculate the wavelength [tex]\lambda[/tex] of these photos in vacuum:
[tex]\begin{aligned}\lambda &= \frac{c}{f} \\ &= \frac{c}{ E/ h} \\ &= \frac{h \cdot c}{E} \\ &\approx \frac{6.62607 \times 10^{-34}\; \rm J \cdot s \times 2.99792 \times 10^{8}\; \rm m \cdot s^{-1}}{3.02639 \times 10^{-19}\; \rm J} \\ &\approx 6.65 \times 10^{-7}\; \rm m \\ &= 6.65 \times 10^{-7}\; \rm m \times \frac{10^{9}\;\rm nm}{1\; \rm m} \\ &= 6.65 \times 10^{2}\; \rm nm\end{aligned}[/tex].
You have 100 mL of a solution of benzoic acid in water; the amount of benzoic acid in the solution is estimated to be 0.30 g. The distribution coefficient of benzoic acid in diethyl ether and water is approxi- mately 10. Calculate the amount of ben- zoic acid that would be left in the water solution after four 20-mL extractions with ether. Do the same calculation using one 80-mL extraction with ether to determine which method is more efficient.
Answer:
The extraction with four 20-mL extractions with ether is more efficient.
Explanation:
We are given the following parameters which are going to help in solving this particular Question.
=> The volume of the solution of benzoic acid in water = 100mL, the estimated amount of benzoic acid in the solution = 0.30 g and the distribution coefficient (approximately ) = 10 = 1/ 10 = 0.1
Therefore, the amount of acid that would be left in the water solution after four 20-mL extractions with ether = 0.3( 0.1 × 100 ÷ 10 + 20)^4 = 0.0037 g.
Also, the amount of acid that would be left in the water solution after one 80-mL extractions with ether = 0.3( 0.1 × 100/ 10 + 80)^1 = 0.033 g.
Since 0.033 g > 0.0037 g, the extraction with four 20-mL extractions with ether is more efficient.
Help me please omg
Answer the following question:
How many moles of ammonia are in 375. mL of a 2.25 M aqueous ammonia solution?
Find the numerical answer for this question and make sure to include the following:
What is the chemical formula for ammonia?
What is the formula for molarity?
When you give your numerical answer, what is the correct significant figures and how do you know that is the correct amount?
Answer:
NH₃
M = n/V(L)
0.844 mol (Both numbers have 3 significant figures so the result has 3 significant figures as well)
Explanation:
Step 1: Given and required data
Volume of solution (V): 375. mLMolar concentration of the solution (M): 2.25 MChemical formula for ammonia: NH₃Step 2: Calculate the moles (n) of ammonia (solute)
Molarity is equal to the moles of solute divided by the liters of solution.
M = n/V(L)
n = M × V(L)
n = 2.25 mol/L × 0.375 L = 0.844 mol (Both numbers have 3 significant figures so the result has 3 significant figures as well)
2 Cu + Cl2 ----> 2 Cuci
If 1.64 moles of chlorine is reacted with 3.23 moles of copper, how many grams of copper I chloride will be made?
(The next question will ask about the limiting and excess reactants for this reaction)
o 320 g
O 160 g
O 162 g
O 325 g
Answer:
320 g.
Explanation:
Hello!
In this case, according to the balanced chemical reaction, we can compute the grams of copper I chloride produced by each reactant, as shown below:
[tex]m_{CuCl}^{by\ Cu}=3.23molCu*\frac{2molCuCl}{2molCu}*\frac{99.0gCuCl}{1molCuCl} =320gCuCl\\\\m_{CuCl}^{by\ Cl_2}=1.64molCl_2*\frac{2molCuCl}{1molCl_2}*\frac{99.0gCuCl}{1molCuCl} =325gCuCl[/tex]
Thus, since copper produces the fewest grams of CuCl, we infer it is the limiting reactant, therefore the correct mass of copper I chloride is 320 g.
Best regards!
5. If the reaction of carbon monoxide and oxygen gas in question 2
produced 7.03E24 molecules of CO2, what is the mass in grams? Use
44g/mol for M.M. of CO2 and round your answer to the nearest whole
number. *
Answer: The mass in grams is 514.8.
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given molecules}}{\text{Avogadros number}}[/tex]
given molecules = [tex]7.03\times 10^{24}[/tex]
Putting in the values we get:
[tex]\text{Number of moles}=\frac{7.03\times 10^{24}}{6.023\times 10^{23}}=11.7moles[/tex]
mass of [tex]CO_2=moles\times {\text {Molar mass}}=11.7mol\times 44g/mol=514.8g[/tex]
The mass in grams is 514.8.
A reaction was set up to convert an alcohol to a carbonyl. Samples of the reaction mixture were checked by infrared spectrometry every couple of minutes. Use the infrared spectra provided to determine if the reaction mixture contains: pure alcohol, a mixture of alcohol and carbonyl, or pure carbonyl. The reaction mixture contains pure carbonyl. pure alcohol. mixture of alcohol and carbonyl. The reaction mixture contains mixture of alcohol and carbonyl. pure carbonyl. pure alcohol.
Answer:
First spectrum = contains only alcohol Compound.
Second spectrum= Contains both alcohol and carbonyl compounds.
Explanation:
The concept known as "spectroscopy'' is an important aspect of Chemistry. It is used in the identification of chemical compounds. Some of the techniques used in spectroscopy is through the use of NMR, IR spectroscopy and UV-Vis spectroscopy.
This question is about IR spectroscopy. Here each functional group has its own unique frequency of absorption. For instance the frequency of absorption of Alkane, C- H( stretch) is 2850 - 3000, alkyne, C-H( stretch) is 3300, amine, N-H(bending) is 1600 and so on.
For the characteristic frequency of absorption found in OH(stretch) is 3300 - 3700. This can be seen in the spectrum given. Thus, OH bond is present.
For carbonyl group, C= O the characteristic absorption frequency is 1670-1820. This frequency can not be found in the first spectrum. But checking the second spectrum a frequency of 1700 can be seen.
Thus, the C=O bond is absent on the first spectrum but present in the second spectrum.
In the second spectrum too, the characteristic frequency of absorption of 3300 is found. Thus, in the second spectrum the compound have both OH and C=O.
The irreversible elementary gas-phase reaction is carried out isothermally at 305 K in a packed-bed reactor with 100 kg of catalyst. The entering pressure was 20 atm and the exit pressure is 2 atm. The feed is equal molar in A and B and the flow is in the turbulent flow regime, with FA0 10 mol/min and CA0 0.4 mol/dm3. Currently 80% conversion is achieved. What would be the conversion
Answer:
0.856.
Explanation:
Lets represent the irreversible elementary gas phase equation of reaction as
A + B -----------------------------------> C + D
We have that the percentage of conversion is 80%.
The pressure, p from the ratio of exit pressure and entering pressure is p = 2/20 = 1/10 = 0.1.
Therefore, n = 1 - p^2/ weight of the catalyst = 1 - 0.1^2/ 100 = 9.9 × 10^-3 kg cat^-.
Now, let's make use of the equation below;
J/ 1 - J = kb^2/ u [ w - nw^2/2] ----------(1).
0.8 / 1- 0.8 = k ( 0.4)^2/ 10 [ 100 - (9.9× 10^-3 × 100^2/ 2] .
k = 4.95 dm^6/ kg.cat .mol.min
The turbulent flow= 1/2 × 9.9 × 10^-3 = 4.95 × 10^-3 kg cat^-.
Thus, making use of the equation (1) again, we have that;
{4.95 × 10^-3 × 0.4}/ 10 × [ 100 - (4.95 × 10^-3 × 100^2)] / 2 = 5.964.
Therefore, a/1 - a = 5.964.
5.964( 1 - a) = a.
5.964 - 5.964a = a.
5.964 = a + 5.964a.
5.964 = 6.964a.
a = 5.964/ 6.964 = 0.856.
Help~... It's "Science". ^W^
Which term is used to describe the variety of inheritable traits in a species? (1 point)
A. Ecosystem diversity
B. Genetic diversity
C. Natural selection
D. Species diversity
The electron configuration of an element is 1s22s2. How many valence electrons does the element have?
1
2
3
4
1s²2s²
#The total electron/proton is the power
2 + 2 = 4
Answer : 4Answer:
Its 4, pls mark as brainliest
Explanation:
What is the oxidation number of bromine in the BrO3- ion?
Why are watersheds important for the maintenance of water quality? Choose all that apply.
Select 2 correct answer(s)
Question 3 options:
they can transfer pollutants
their soil and plants can filter and clean water
they cause precipitation and acid rain
they cause floods
Answer:
its A and D
Explanation:
i took the quiz
Answer:
a and d
Explanation:
Draw the structure of the major organic product(s) for the following reaction between an acetylenic anion and an alkyl halide. (The reaction stoichiometry is 1:1.) A carbon carbon triple bond where carbon 1 is a carbanion with a lone pair and carbon 2 is bonded to methyl. This reacts with a 5 carbon chain where carbon 3 has a bromine substituent.
Answer:
See explanation below
Explanation:
In this case, we are having a reaction between an anion and alkyl halide. The carbon 1 of the anion will act as nucleophile and will attack the electrophile, which is 5 carbon chain with the bromine in the third carbon.
Now, the nucleophyle is an alkyne of 3 carbon. According to the description, it should be:
CH₃ - C ≡ C⁻
And the alkyl halide is:
CH₃ - CH₂ CH(Br) - CH₂ - CH₃
And the final product after the reaction would be the following:
CH₃ - C ≡ C - CH - (CH₂CH₃)₂
However, in the attached picture you can see this better and the mechanism of reaction.
Hope this helps
which has more gravity
A. Earth
B. Sun
C. Saturn
B
the sun!
yay
!!!!!!!!!!!
Answer:
EARTH
Explanation:
Earth‘s gravity, as already noted, is equivalent to 9.80665 m/s² (or 32.174 ft/s²). This means that an object, if held above the ground and let go, will accelerate towards the surface at a speed of about 9.8 meters for every second of free fall.
during the rock cycle___ follows erosin
Answer:
i dont get it
Explanation:
Answer:
deposition
Explanation:
How many moles of water can be formed from 23.9 mol of oxygen gas?
H2 + O2 --> H20
Hint: Is it balanced?
Answer:
47.8 moles of H₂O.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2H₂ + O₂ —> 2H₂O
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of H₂O
Finally, we shall determine the number of mole of water, H₂O, produced by the reaction of 23.9 moles of O₂. This can be obtained as follow:
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of H₂O.
Therefore, 23.9 moles of O₂ will react to produce = 23.9 × 2 = 47.8 moles of H₂O.
Thus, 47.8 moles of H₂O were obtained from the reaction.
Which of the following are examples of limiting factors? a. water b. sunlight c. available mates d. all of the above
Answer: I believe the answer is D.) All of the above.
Explanation:
explain why the atomic radius of fluorine is smaller than that of lithium
1. Common knowledge : Go to the right of periodic table, the atomic radius is decreasing
2. Flurine has 9 protons and lithium has 3 protons. you know that the electron is attracted with the centre of the atom, that's why more proton, more 'energy' that attract to the centre and that's why it make the shape of the atom is smaller
The hydronium ion concentration of an aqueous solution of 0.502 M pyridine (a weak base with the formula C5H5N) is
Answer:
1.99×10¯¹⁴ M
Explanation:
We'll begin by writing the balanced dissociation equation of pyridine. This is illustrated below:
C₅H₅N + H₂O <=> C₅H₆N⁺ + OH¯
From the balanced equation above,
1 mole of C₅H₅N produced 1 mole of OH¯.
Therefore, 0.502 M C₅H₅N will also produce 0.502 M OH¯.
Finally, we shall determine the concentration of hydronium ion, H₃O⁺ in the solution. This can be obtained as follow:
Concentration of Hydroxide ion [OH¯] = 0.502 M
Concentration of hydronium ion [H₃O⁺] =?
[H₃O⁺] [OH¯] = 1×10¯¹⁴
[H₃O⁺] × 0.502 = 1×10¯¹⁴
Divide both side by 0.502
[H₃O⁺] = 1×10¯¹⁴ / 0.502
[H₃O⁺] = 1.99×10¯¹⁴ M
Thus, the concentration of hydronium ion, H₃O⁺ in the solution 1.99×10¯¹⁴ M
Calculate the mass of water produced from the reaction of 24.0 g of H2 and 160.0 g of O2. What is the limiting reagent?
Answer: [tex]O_2[/tex] is the limiting reagent, 180 g of water is produced
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} H_2=\frac{24.0g}{2g/mol}=12moles[/tex]
[tex]\text{Moles of} O_2=\frac{160.0g}{32g/mol}=5moles[/tex]
[tex]2H_2+O_2\rightarrow 2H_2O(g)[/tex]
According to stoichiometry :
1 mole of [tex]O_2[/tex] require 2 moles of [tex]H_2[/tex]
Thus 5 moles of [tex]O_2[/tex] will require=[tex]\frac{2}{1}\times 5=10moles[/tex] of [tex]H_2[/tex]
Thus [tex]O_2[/tex] is the limiting reagent as it limits the formation of product and [tex]H_2[/tex] is the excess reagent.
As 1 mole of [tex]O_2[/tex] give = 2 moles of [tex]H_2O[/tex]
Thus 5 moles of [tex]O_2[/tex] give =[tex]\frac{2}{1}\times 5=10moles[/tex] of [tex]H_2O[/tex]
Mass of [tex]H_2O=moles\times {\text {Molar mass}}=10moles\times 18g/mol=180g[/tex]
Thus 180 g of [tex]H_2O[/tex] will be produced from the given masses of both reactants.
Gold's natural state has a definite shape and a definite volume. What is gold's natural state(s)?
Answer:
If your asking what golds natural state of matter is it's solid.
Explanation:
Answer:
the answer is soild
Explanation:
i did it on edge :)
**will give brainlists if correct answer***
Predict all of the products of the incomplete reaction shown below.
K+ Cl2 →
A)KCIO3
B)K2
С)КСІ
D)KCI2
Answer:
C)
Explanation:
What is true of dynamic equilibrium?
A. All reactants are turning into products.
B. No more changes are happening.
C. All the changes to a system cancel out.
D. The total amounts of products and reactants are fluctuating.
SUBMIT