Answer:
a
Explanation:
because physical changes are reversible while chemical changes are irreversible
How
many
molecules are in 8.55x10-15 moles of a substance
Answer:
Know this
1mole of a substance contains 6.022x10²³molecules
Now
8.55x10^-15moles x 6.022x10²³molecules/1mole
=5.15x10^9molecules.
3. 7moles of Ba(NO3)2 is dissolved in 75kg of distilled water.
What is the boiling point of this solution? Hint: Find molality first.
Answer:
100.14°C
Explanation:
The boling point elevation is a colligative property that describes the increasing in boiling point of a solution regard to the boiling point of the pure solvent. The equation is:
ΔT = Kf*m*i
Where ΔT is boiling point elevation
Kf is boiling point elevation (0.51°C/m for water)
m is molality of the solution (7moles Ba(NO3)2 / 75kg = 0.09333m
i is Van't Hoff factor = 3 for Ba(NO3)2 (Because its dissolution produce 3 ions = Ba²⁺ and 2 NO₃⁻
Replacing:
ΔT = 0.51°C/m*0.09333m*3
ΔT = 0.14°C is the boiling point elevation
As the boiling point of water is 100°C, the boiling point of the solution is:
100°C + 0.14°C =
100.14°C
For many purposes, we can treat propane (C3H8) as an ideal gas at temperatures above its boiling point of -24C Suppose the temperature of a sample of propane gas is lowered from 14.0c to -1.0c and at the same time the pressure is changed.
If the initial pressure was0.75 kPa and the volume decreased by55.0% what is the final pressure? Round your answer to the correct number of significant digits.
it's 75 k bro thats the answer
Which form of emission is commonly not written in nuclear equations because they do not affect charges, atomic numbers, or mass numbers?
alpha particle
beta particle
gamma ray
Answer: It is Gamma ray
Answer:
C. gamma ray
(Photo for proof at the bottom.)
Explanation:
A gamma ray is a type of radiation that occurs when an unstable nucleus emits a photon, the smallest unit of light. A photon has no mass or charge. Atomic and mass numbers are written based on the mass of the atom. But since no mass is lost when a photon is emitted, writing the emission of it isn't necessary.
Here's a photo of Edge, good luck.
Hi can someone who know the answers tell me what it is and pls don't send me a link also don't send me the wrong answers if you don't know it's ok :)
Answer:
you diba ikaw ang nagpamalimali diba no
How does the composition of the nucleus change during fission, fusion, and radioactive decay?
The composition and mass of the nucleus changes during fission, fusion and nuclear decay process. During fission the nuclei breaks to light nuclei and in fusion the mass of nuclei formed is increased and in radioactive decay, the nuclear mass decreases.
What is nuclear fission?Nuclear fission is the process of breaking of a heavy nucleus into light nuclei with the release of energy. Hence, fission changes the identity of the atomic nuclei and form to light nucleus.
In nuclear fusion, two light nuclei fused up to form a heavy nucleus. Hence, the new composition changes the identity of the product. The number of protons, neutrons or electrons are differed in both fusion or fission.
Radioactive elements undergo nuclear decay by the emission of charged particles and it will reduce the atomic number or mass number or both based on the type of decay.
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Potassium hydroxide is partially soluble as shown by the
following reaction:
KOH(s) K+ (aq) + OH(aq)
What is the poH of a 3.32 x 10-5 M KOH solution?
pOH =
Your answer should be rounded to three significant figures. Do not Include
units in your answer.
Answer: 4.48 or 4.47
Alex built a model to show how light bends when placed into water. To do this, Alex filled a fish tank up with water, and shined a green laser through the water. The angle he shined the laser into the fish tank is the line above the water, and the angle that the light bent is seen below the water. What is a limitation of this model? The model cannot show how light bends. The model is unable to use different colors of light The model cannot calculate the speed of light The model is not 3 dimensional
Answer:
The model cannot show how light bends.
Explanation:
Find the hydroxide concentration of a LiOH soultion that has a pOH of 8.65.
[OH] = _____ (round to 2 decimal places)
Answer: i need help
Explanation:
How many iron atoms are in Fe2O3?
Answer:
2 iron atoms in Fe2O3
why dil. sulphuric acid cannot be used instead of dil.hcl in lab preparation of carbon dioxide gas?
Answer:
Because Sulphuric acid(H2SO4) is one of the substance which have a very high vigourous reaction if mix with chemicals thats why we take the same sulphuric acid but having lighter effects known to be as Dil.Sulphuric And so it is generally use for precaution while during experimentations Thats why we use it.
Hope it helps
You are given 250 mL of a 12.0 M solution of KNO3. To obtain a 5.0 M, to what volume does the solution need to be diluted to?
600 ml
104.17 mL
0.24 mL
60 mL
Answer:
600 mL
Explanation:
molarity 1 * volume 1 = molarity 2 * volume 2. So this means 12 * 250 = 3000 and divide that by 5 to get 600 mL.
Blank O2 + blank Mg arrow blank MgO
Select the coefficients that balance the equation:
MgO *
A) 1,1,1
B) 1,2,2
C) 2,3,4
D) 1,4, 2
Answer:
its a
Explanation:
a
- How much power does it take to lift a
1,000 N load 10 m in 20 s?
Answer:
"500 Joule/sec" is the right answer.
Explanation:
The given values are:
Force,
F = 1000 N
Velocity,
s = 10 m
Time,
t = 20 s
Now,
The power will be:
= [tex]\frac{Force\times Velocity}{Time}[/tex]
On putting the values, we get
= [tex]\frac{1000\times 10}{20}[/tex]
= [tex]\frac{10000}{20}[/tex]
= [tex]500 \ Joule/sec[/tex]
How do gas particles respond to an increase in volume?
When the volume of a gas is increased, the gas particles respond by spreading out and occupying a larger space. This results in a decrease in the density of the gas and a decrease in the frequency of collisions between the gas particles.
How do gas particles respond to an increase in volume?As the gas particles spread out, the pressure exerted by the gas decreases.
This is because the pressure of a gas is directly proportional to the number of collisions per unit area of the container walls. When the volume increases, the same number of gas particles are distributed over a larger area, reducing the frequency of collisions and thus decreasing the pressure.
In summary, an increase in volume causes gas particles to spread out, resulting in a decrease in density and a decrease in pressure.
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¿Cómo se llama el grupo IIA de la tabla periódica?
Answer:
los metales alcalinotérreos: berilio (Be), magnesio (Mg), calcio (Ca), estroncio (Sr), bario (Ba) y radio (Ra).
o simplemente llamado grupo 2A
Explanation:
4. A blue light is shined on objects X and Y. Object X appears to be blue, and object Y appears to
be black. Which of the following is correct?
A. Object X absorbs blue light, and object Y reflects blue light.
B. Object X reflects blue light, and object Y absorbs blue light.
C. Object X must be black, and object Y must be blue.
D. Object X must be blue, and object Y must be black.
A blue light is shined on objects X and Y. Object X appears to be blue, and object Y appears to be black when Object X reflects blue light, and object Y absorbs blue light. Hence option B is correct.
What is light ?Visible light spectrum is nothing but the range of wavelength of radiation from 4000 angstrom to 7000 angstrom(Violet to Red). light is a energy packet. Every Photon having different wavelength travels with same velocity c (velocity of light). When we focus numbers of colors from visible spectrum to a point, that point appears as a white light. hence white light is composed of numbers of Colors in it.
When we pass white light through a prism, as white light enters in the prism all the colors having different wavelength travels with different velocity in the prism due to that there is separation of colors from the white light. Therefore we get different colors of white light in the prism this phenomenon is know as dispersion of light.
Light can be reflected, absorbed, transmitted diffracted and scattered etc.
α + β + ν = 1 where α, β, ν are coefficient of absorption, reflection and transmission.
When any object appears to be black it means that radiation has been absorbed by that body, it has high absorption coefficient. and when a body appears to be colored, it means that object has reflected the particular color, it having high reflection coefficient.
Hence option B is correct.
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What will the change in temperature be when 90 J are applied to 15 g of gold. (Cgold = 0.126 J/gºC)
Round your answer to the nearest whole number.
°C
E
3
4
5
Next
O
I 17
Answer:
48 °C
Explanation:
q = 90J
m = 15 g
C = 0.126 J/gºC
q = mct
90 = (15)(0.126)t
t = 47.62 °C = 48 °C
Answer:
Explanation:
Formula
E = m * c * Δt
Δt is what you seek.
Givens
E = 90 joules
m = 15 grams
c = 0.126
Solution
90 = 15 * 0.126 * Δt Divide by 15
90/15 = 15/15 * 0.126 * Δt
6 = 0.126 * Δt Divide by 0.126
6/0.126 = Δt
47.619 = Δt
Δt = 48 oC
Calculate the mass of Iron in 40g of Fe203
Answer:
Explanation:
what is the mass of 0.200 mol of calcium
Balance the following Chemical Equation:
NaBr +CaCl2-> NaCl+ CaBr2
How many moles of nitrogen are in 12 grams
Answer:
Explanation:
The chemical formula of nitrogen is N2
A mol of Nitrogen atoms = 14 grams
So N2 will have a molar mass of 14 * 2 = 28 grams
number of moles of N2 = given mass / molar mass
number of moles of N2 = 12 / 28
number of moles of N2 = 0.4286 mols
How would you find the density of a can of soda pop?
A. Find the mass of the can of soda pop and then multiply by the number of cubic centimeters in the can
B. Find the mass of the can of soda pop and then divide by the number of cubic centimeters in the can
C. Convert a gallon into cubic centimeters and then divide by the mass of the can of soda pop
D. Convert a gallon into cubic centimeters and then subtract the mass of the can of soda pop
Answer:
it's A.
Explanation:
have uh good day ma :)))))))
In steps 3 and 4 of the citric acid cycle, successive oxidations produce ________ as a waste product and the four-carbon carrier ________. In steps 3 and 4 of the citric acid cycle, successive oxidations produce ________ as a waste product and the four-carbon carrier ________. CO2; malate CO2; succinyl-SCoA ADP; oxaloacetate ADP; succinyl-SCoA CO2; oxaloacetate
Answer:
CO2; succinyl-SCoA
Explanation:
Citric acid cycle, also called Krebs cycle is the second stage of aerobic cellular respiration, which occurs in the mitochondrion. The kreb's cycle is made up of 7 distinct steps, with each involving series of enzymatic reactions.
According to this question, step 3 and 4 of the citric acid cycle involves an oxidation and decarboxylation reaction to produce 2 molecules of carbon dioxide (CO2) and a 4-carbon compound called succinyl group. A coenzyme A binds to the succinyl group to form succinyl-SCoA.
Some sugar is added to cold water in a beaker.
After some time, all the sugar dissolves and spreads throughout the water.
(a)(¡) Name the process that occurs which causes the sugar to spread throughout the water.
(ii) State two ways to make the sugar dissolve more quickly.
(b) Pure water can be obtained from the sugar solution using this apparatus.
Name the process used to obtain pure water from the sugar solution.
i) diffusion, concentration differences in gas and fluid disappears when particles of sugar are evenly spread in solution
ii) Heating the solution, mixing the solution
b) Distillation, solution is heated until water is vaporized and water vapour condenses in another part of apparatus.
Sugar is separated from water by evaporation of the sugar solution to dryness.
i) The process of that causes the sugar to spread throughout the water is called solvation. Solvation simply refers to the interaction of a solute and a solvent.
ii) To make the sugar to dissolve quicker;
The temperature of the solvent can be raisedThe system can be stirred periodicallyb)To obtain pure water from sugar, the sugar is evaporated to dryness. This is done by heating the sugar in a set up as shown in the image attached.
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Calcula cuantos mililitros de oxigeno se necesitan para quemar 3.5 ml de C₆H₆ a CNTP, la reacción sin balancear es la siguiente: C₆H₆ + O₂ → CO₂ + H₂O
Answer:
[tex]26.25mL \ O_2[/tex]
Explanation:
¡Hola!
En este caso, dado que se nos da reacción de combustión del benceno, primero debemos balancearla como se muestra a continuación:
C₆H₆ + ¹⁵/₂ O₂ → 6CO₂ + 3H₂O
Vemos que hay una relación molar entre el benceno y oxígeno de 1:¹⁵/₂, por lo que la relación de volúmenes es:
[tex]3.5 mL\ C_6H_6*\frac{15/2\ mL\ O_2}{1mL\ C_6H_6} \\\\=26.25mL \ O_2[/tex]
¡Saludos!
Glycerol has a molar mass of 92.09g/mol. Its percent composition is: 39.12% C, 8.75% H,
and 51.12% O. What is the molecular formula for glycerol?
Answer:
Molecular formula => C₃H₈O₃
Explanation:
From the question given above, the following data were obtained:
Carbon (C) = 39.12%
Hydrogen (H) = 8.75%
Oxygen (O) = 51.12%
Molar mass of compound = 92.09 g/mol
Molecular formula =?
Next, we shall determine the empirical formula of the compound. This can be obtained as follow:
C = 39.12%
H = 8.75%
O = 51.12%
Divide by their molar mass
C = 39.12 / 12 = 3.26
H = 8.75 / 1 = 8.75
O = 51.12 / 16 = 3.195
Divide by the smallest
C = 3.26 / 3.195 = 1
H = 8.75 / 3.195 = 2.7
O = 3.195 / 3.195 = 1
Thus, the empirical formula is CH₂.₇O
Finally, we shall determine the molecular formula of the compound. This can be obtained as follow:
Empirical formula = CH₂.₇O
Molar mass of compound = 92.09 g/mol
Molecular formula =?
Molecular formula = Empirical formula × n
Molecular formula = [CH₂.₇O]ₙ
92.09 = [12 + (2.7×1) + 16] × n
92.09 = 30.7n
Divide both side by 30.7
n = 92.09 / 30.7
n = 3
Molecular formula = [CH₂.₇O]ₙ
Molecular formula = [CH₂.₇O]₃
Molecular formula = C₃H₈O₃
What would be the volume, in liters measured at STP, of 9.75 moles of carbon monoxide?
I
The total pressure of two unknown gases is 5 kPa. The partial pressure of one of the gases is 2.345 kPa, what is the partial pressure of the other gas?
Answer:
[tex]p_2=2.655kPa[/tex]
Explanation:
Hello there!
In this case, according to the Dalton's law, which states that the total pressure is equal the sum of the pressures of the gases in the mixture, we write the following for this system:
[tex]P_T=p_1+p_2[/tex]
Thus, we solve for the partial pressure of the gas #2 as shown below:
[tex]p_2=P_T-p_1\\\\p_2=5kPa-2.345kPa\\\\p_2=2.655kPa[/tex]
Best regards!
Brakes are to a car as
to a nuclear-fission chain reaction.
A. fuel rods are
B. proliferation is
C. free neutrons are
D. control rods are
Answer:
D. control rods are
I hope dis helps :3
Brakers are to a car as control rods are to a nuclear-fission chain reaction. The correct option is D.
What is a nuclear-fission chain?A chain reaction occurs when neutrons generated during fission cause subsequent fission in at least one more nucleus.
This nucleus creates neutrons, and the cycle continues.
The process can be either controlled (nuclear power) or uncontrolled (nuclear weapons) (nuclear weapons).
Thus, the correct option is D. control rods are.
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