Answer:
B) the freezing point decreases and the vapor pressure at 25°C decreases.
Explanation:
Colligative properties are those properties that depend on the amount of solute in solution. Both freezing point and vapour pressure are colligative properties.
As the number of nonvolatile solute particles increases, the freezing point of the solution decreases. This is known as freezing point depression.
Similarly, "Vapor pressure is a colligative property, so the vapor pressure of solutions is directly proportional to the amount of solute present in a solution. When a solute is present in a solvent, the vapor pressure is lowered because fewer solvent molecules are present at the top of the solution" (Lumen Learning).
Answer:
f u moderators
Explanation:
euurhtiuubbfjdhbgvzrbsf im sorry
write the chemical equation of the reaction with a change in colour
Answer:
(i) Change in colour (ii) Change in temperature (iii) Formation of precipitate
Explanation:
(i) Change in colour: Reaction between lead nitrate solution and potassium iodide solution. Pb(NO3)2(aq)+2KI → PbI2(s)+2KNO3(aq) In this reaction, colour changes from colourless to yellow. (ii)Change in temperature: Action of dilute sulphuric acid on zinc. Zn(s) + H2SO4(aq) → ZnSO4(aq) + H2 In this reaction, heat is evolved (iii) Formation of precipitate: Action of barium chloride on sodium sulphate. BaCl2(aq) +Na2SO4(aq) → BaSO4(s) +2NaCl(aq) BaSO4(s)
In the isotope Carbon-14, what does the number 14 represent?
Answer:
number of tamed protons and neutrons
Is this the correct formula for magnesium acetate? Mg(C2H3O)2
Answer:
no
Explanation:
magnesium acetate= Mg(C2H3O2)2
In order to dissolve a chemical sample in a recrystallization solvent, add the room-temperature solvent ___________ in an Erlenmeyer flask on a hot plate. Turn on the heat, starting at __________________. Using a _______, add additional solvent from a second container on the heat source. Swirl the sample flask after each addition, and try to add _______________ in order to dissolve the solid.
Answer:
just until it covers the sample
a low setting and increasing gradually
pipet
as little solvent as possible
Explanation:
In order to dissolve a chemical sample in a recrystallization solvent, add the room-temperature solvent just until it covers the sample in an Erlenmeyer flask on a hot plate. Turn on the heat, starting at a low setting and increasing gradually. Using a pipet, add additional solvent from a second container on the heat source. Swirl the sample flask after each addition, and try to add as little solvent as possible in order to dissolve the solid.
the amount of copper sulphate used in dissolution is
Answer:
80 gm/mol
Explanation:
it may be helpful
Glucose is the monomer in the natural polymers ____________________ and cellulose.
Answer:
Starch
I hope this helps
To date, scientific tests of astrology have never found that its predictive methods work.
True
False
true______________________
5.6 g of an organic compound on burning with excess
of oxygen gave 17.6 g of CO2, and 7.2 g of H,O. The
organic compound is :
Answer:organic compound is : C₄H₈
Explanation: The equation of the reaction of the organic compound burning with excess oxygen gives us the general equation as
C xHy + 1/2(x+ y/2 )O₂ → xCO₂ + y/2H₂O
We first find the number of moles of CO₂ and H₂O
Number of moles of CO₂= Mass/ molar mass
= 17.6g/ 44g/mol ( 12+ 16 x2)
=0.4 moles
Number of moles of H₂O= Mass/ molar mass
= 7.2g/ 18g/mol ( 1 X 2+ 16)
=0.4 moles
From the reaction , we can see that
x = 0.4
and [tex]\frac{y}{2}[/tex]= 0.4 such that y= 0.4 x 2= 0.8
Their ratios become
[tex]\frac{x}{y}[/tex] =[tex]\frac{0.4}{0.8}[/tex]= [tex]\frac{4}{8}[/tex]
Therefor the organic compound CxHy = C₄H₈
1. Fill in the blanks. Example: A nitrogen atom takes on a 3- charge when it forms an anion and becomes nitride. a. A magnesium atom takes on a ___ charge when it forms a(an) ____ion and becomes . b. A chlorine atom takes on a ___ charge when it forms a(an) ____ion and becomes . c. An oxygen atom takes on a ___ charge when it forms a(an) ____ion and becomes . d. A potassium atom takes on a ___ charge when it forms a(an) ____ion and becomes .
Answer: a. +2, cation and magnesium ion .
b. -1, anion, chloride
c. -2, anion, oxide
d. +1. cation , potassium ion
Explanation:
When an atom accepts an electron negative charge is created on atom and is called as anion.
When atom loses an electron positive charge is created on atom and is called as cation.
Magnesium (Mg) with atomic number of 12 has electronic configuration of 2,8,2 and thus it can lose 2 electrons to form [tex]Mg^{2+}[/tex] cation and becomes magnesium ion.
Chlorine (Cl) with atomic number of 17 has electronic configuration of 2,8,7 and thus it can gain 1 electron to form [tex]Cl^{-}[/tex] anion and becomes chloride.
Oxygen (O) with atomic number of 8 has electronic configuration of 2,6 and thus it can gain 2 electrons to form [tex]O^{2-}[/tex] anion and becomes oxide.
Potassium (K) with atomic number of 19 has electronic configuration of 2,8,8,1 and thus it can lose 1 electron to form [tex]K^{+}[/tex] cation and becomes potassium ion.
Aside from invasives like the crown-of-thorns starfish, what other factor is killing the Great Barrier Reef?
O increased temperatures
O overactive algae
O reactive forms of oxygen
O coral bleaching
Answer:
increased temperatures
Explanation:
The temperatures are increasing in the ocean because of ocean warming, by climate change. The heat in the ocean stresses healthy corals, which drains them of their vibrant colors, known as bleaching.
An allergy medicine is usually stored in a cabinet at room termperature where its molecules move around each other. By
mistake, an intern transferred energy into the medicine. After one hour, the intern found the medicine and noticed that it
was a liquid. How were the molecules moving when the intern found the medicine? Explain why the molecules were
moving this way after the intern transferred energy ito the medicine.
Answer:
hello, can you pleas egive me the answer? i have the same exact question. thank you!
Explanation:
I need help ASAP pls
Answer:
A should be the swer n
Explanation:
Which molecular compound is composed of the greatest number of atoms?
A. Carbon Dioxide
B. Dinitrogen Monoxide
C. Potassium Phosphide
D. Sodium Chloride
Answer:
Answer:
Potassium Nitride is composed of the greatest number of atoms.
Explanation:
find the number of atoms present in each compound we will write down their molecular formulas and then we will add up the number of atoms present in them.
A: Dinitrogen Monoxide:
Chemical formula of Dinitrogen Monoxide is N₂O. Therefore, it contains two atoms of Nitrogen and one atom of oxygen Hence, in total it contains 3 atoms.
B: Sodium Chloride:
Chemical formula of Sodium Chloride is NaCl. Therefore, it contains one atom of Sodium and one atom of Chlorine Hence, in total it contains 2 atoms.
C: Potassium Nitride:
Chemical formula of Dinitrogen Monoxide is K₃N. Therefore, it contains three atoms of Potassium and one atom of Nitrogen Hence, in total it contains 4 atoms.
D: Carbon Dioxide:
Chemical formula of Carbon Dioxide is CO₂. Therefore, it contains one atom of Carbon and two atoms of Oxygen Hence, in total it contains 3 atoms.
Explanation:
What happens when an electron jumps from energy level 1 to energy level 2 in an atom?
I need help can somebody help me
Answer:
they slow down
Explanation:
Water molecules slow down as they lose energy. The molecules become closer together and decrease the volume.
Farsighted people have trouble seeing objects that are close to their eyes.
True
False
Which half reaction is associated with the anode?
Sn(s) —> Sn2+ (aq) + 2e-
Sn2+ (aq) + 2e- → Sn(s)
Pb2+ (aq) + 2e-->Pb(s)
Pb(s)->Pb2+ (aq) + 2e-
Answer:
vgf
Explanation:
Answer:
its either A or B
Explanation:
took the test twice and guessed LOL
its not C or D :>
If two-parent with AB blood group claim and say that they have a baby with O blood group is born to them and it is their own baby and not adopted. Do you think they are speaking the truth?
who knows this answer
There are two isotopes of an unknown element, X-19 and X-21. The abundance of X-19 is 14.55%. A weighted average uses the percentages of each isotope to scale their contribution to the total mass. Each isotope's contribution is the percentage (in decimal form) multiplied by the mass of the isotope. What is the contribution (in amu) to the weighted average from the X-19 isotope, which has a mass of 19.00 amu
Answer:
2.765amu is the contribution of the X-19 isotope to the weighted average
Explanation:
The average molar mass is defined as the sum of the molar mass of each isotope times its abundance. For the unknown element X that has 2 isotopes the weighted average is defined as:
X = Mass X-19 * Abundance X-19 + MassX-21 * Abundance X-21
The contribution of the X-19 isotope is its mass (19.00 amu) times its abundance (14.55% = 0.1455). That is:
19.00amu * 0.1455 =
2.765amu is the contribution of the X-19 isotope to the weighted average
What mass of KNO, will dissolve in 100 g of water at 100°C?
Answer:
About 170-180 grams of potassium nitrate are completely dissolved in 100 g.
Explanation:
Hello!
In this case, according to the reported solubility data for potassium nitrate at different temperatures on the attached picture, it is possible to bear out that about 170-180 grams of potassium nitrate are completely dissolved in 100 g; considering that the solubility is the maximum amount of a solute that can be dissolved in a solvent, in this case water.
Best regards!
An adaptation is best described as occurring over which time scale? *
(10 Points)
O A. over many eras
O B. over many generations
O C. over one generation
D. over the lifetime of one individual
Answer:
over many eras
Explanation:
In an ecosystem, an adaptation is best described as occurring over many generations.
What is an ecosystem?Ecosystem is defined as a system which consists of all living organisms and the physical components with which the living beings interact. The abiotic and biotic components are linked to each other through nutrient cycles and flow of energy.
Energy enters the system through the process of photosynthesis .Animals play an important role in transfer of energy as they feed on each other.As a result of this transfer of matter and energy takes place through the system .Living organisms also influence the quantity of biomass present.By decomposition of dead plants and animals by microbes nutrients are released back in to the soil.
There are various types of ecosystem present in the environment.
Learn more about ecosystem,here:
https://brainly.com/question/1673533
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Which of the following is a redox reaction?
A. CuO + H2SO4 → CuSO4 + H2O
B. 3MnO2 + 4A1 3Mn + 2A120,
C. MgCO, → MgO + CO2
D. Mg(OH)2 + 2HCl → MgCl2 +H20
Answer:
a
Explanation:
the answer to the question is a
Among the following chemical equations, redox reaction is [tex]3 MnO_2+4 Al\rightarrow 3 Mn +2 Al_2O[/tex].
The redox reaction can be defined as a reaction that involves the transfer of electrons between two species. Redox reactions comprise of two parts a reduced part and an oxidized part, which occur simultaneously . The part which is reduced gain electrons and hence there is a increase in oxidation state of the species.
While, the part which is oxidized looses electrons and hence there is a decrease in oxidation state of the species.During redox reactions, there is no net change in the number of electrons . Electrons which are given off in oxidation are used up in reduction.
Therefore, the correct option is B.
Learn more about redox reactions,here:
https://brainly.com/question/28300253
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Suppose that X represents an arbitrary cation and that Y represents an anionic species. Using the charges indicated in the superscript of X and Y, fill in the remaining blanks below by writing the appropriate subscript for each X and Y to balance the net charge on the ionic XaYb compound formed (where a and b represent positive, whole numbers of X and Y, respectively).
Y- Y2- Y3-
X+
X2+ XY2
X3+
Answer:
See explanation.
Explanation:
Hello!
In this case, when having the cationic and anionic species with the specified charges, in order to abide by the net charge rule, we need to exchange the charges in the form of subscripts and without the sign, just as shown below:[tex]X^{m+}Y^{n-}\rightarrow X_nY_m[/tex]
Thus, for all the given combinations, we obtain:
- Y⁻
[tex]X^+Y^-\rightarrow XY\\\\X^{2+}Y^-\rightarrow XY_2\\\\X^{3+}Y^-\rightarrow XY_3[/tex]
- Y²⁻
[tex]X^+Y^{2-}\rightarrow X_2Y\\\\X^{2+}Y^{2-}\rightarrow X_2Y_2\rightarrow XY\\\\X^{3+}Y^{2-}\rightarrow X_2Y_3[/tex]
- Y³⁻
[tex]X^+Y^{3-}\rightarrow X_3Y\\\\X^{2+}Y^{3-}\rightarrow X_3Y_2 \\\\X^{3+}Y^{3-}\rightarrow X_3Y_3\rightarrow XY[/tex]
Best regards!
Charcoal from the dwelling level of the Lascaux Cave in France gives an average count of 0.97 disintegrations of C-14 per minute per gram of sample. Living wood gives 6.68 disintegrations per minute per gram. Estimate the date of occupation and hence the probable date of the wall painting in the Lascaux Cave. (Half-life of C-14 is 5568 years)
Answer:
15502 years
Explanation:
From;
0.693/t1/2 = 2.303/t log [Ao]/[A]
Where;
t1/2 = half life of C-14
t = time taken
[Ao] = count rate of living sample
[A] = count rate of the charcoal under study.
0.693/5568 = 2.303/t log (6.68/ 0.97)
1.245 * 10^-4 = 2.303/t log (6.887)
1.245 * 10^-4 = 1.92998/t
t = 1.92998/1.245 * 10^-4
t = 15502 years
At STP, in the equation C(g) + O2(g) --> CO2(g), one liter of O2 yields how many liters of CO2?
Answer:
3 I think but ask someone else too
What is the solar radius of a main sequence star?
Answer:I'm going to give some fictitious values just so that we can get some perspective on the matter.
Let's say that the surface temperature of our sun is 10, the surface temp of the bigger star- the red giant formed from leaving the main sequence, has a temp of 0.2. of that- 2.
We can also say that the radius of our sun is 10, and the radius of the red giant is 1000. (100 times more)
Using the equation:
L
=
σ
A
T
4
σ
= The Stefan-Boltzmann constant =
5.67
×
10
−
8
But we can ignore the constant, as we are only interested in a ratio of these values.
L
S
u
n
=
4
π
(
10
)
2
×
10
4
=
1.26
×
10
7
L
S
t
a
r
=
4
π
(
1000
)
2
×
2
4
≈
2.01
×
10
8
2.01
×
10
8
1.26
×
10
8
≈
16
So the newly formed, red giant star is almost 16 times more luminous than the sun. This is owing to the increased surface area of the star due to the massively increased radius.
A small sidenote:
There is an equation that might be useful for comparing the radii, temperature and luminosity of main sequence stars. As red giants are not on the main sequence it could not be used here, but if you stumble across a question where they ask you to find the radius, luminosity or temperature given the other two, you can relate it to the sun's characteristics:
r
s
t
a
r
r
s
u
n
=
√
L
s
t
a
r
L
s
u
n
×
(
T
s
u
n
T
s
t
a
r
)
2
(I know, it's not a beauty to look at- but it works)
Where
X
s
u
n
is the radius, temperature, and luminosity of the sun. These are not often given in numerical values, but this equation serves well when asked to find e.g the radius of a star, in solar radii given that a star is twice as luminous and has 5 times the temperature of that of the sun.
Hence:
T
s
t
a
r
=
5
T
s
u
n
L
s
t
a
r
=
2
L
s
u
n
r
s
t
a
r
r
s
u
n
=
√
2
L
s
u
n
L
s
u
n
×
(
T
s
u
n
5
T
s
u
n
)
2
(cancel the common terms)
r
s
t
a
r
r
s
u
n
=
√
2
×
(
1
5
)
2
r
s
t
a
r
≈
0.057
r
s
u
n
(divide both sides by 0.0057)
17.5
r
s
t
a
r
≈
r
s
u
n
So the star's radius is almost 17.5 times that of the sun.
Hopefully, you find this info useful!
Explanation:
How many pounds of ice are required to absorb 4900 kJ of heat as the ice melts? The heat of fusion of water is 0.334 kJ/g.
help pls
Answer:
Q = ΔH fusion * mass (g)
when we have:
ΔH fusion (the heat (or enthalpy) of fusion = 0.334 kJ/g
and mass of ice = 22.4 g
so by substitution, we can get the energy (Q) required to melt this mass of ice:
∴ Q = 0.334KJ/g * 22.4 g
= 7.48 KJ
∴ the energy required to melt 22.4 g of ice is = 7.48 KJ
Explanation:
In the benzene molecule, carbon atoms form a ring with alternating single and double bonds in between each of them. Each carbon atom forms one σ bond with one carbon atom and one σ and one π bond with another. The π bonding electrons are delocalized over the entire molecule. Thus, benzene is a resonance hybrid of two equivalent structures, and the single and double bonds oscillate from one position to the other.
Required:
Calculate the bond order for one carbon-carbon bond in the benzene molecule, taking σ and π bonding into consideration.
Answer:
1.5
Explanation:
From;
BO = ½(B – A)
BO= Bond order
B= Number of bonding electrons
A = Number of antibonding electrons
For the sigma bonds, there are 2 bonding electrons and 0 nonbonding electrons.
σ BO = ½(B – A) = ½(2 – 0) = 1
π bond order for 6 C-C bonds;
π BO = ½(B – A) = ½(6 – 0) = 3
For each π bond, BO = 3/6 = 0.5.
Hence, for a single C-C bond in benzene, the total Bond order = σ + π = 1 + 0.5 = 1.5.
Question 10 of 35
A red blood cell can be used to model a typical animal cell.
What would happen to a red blood cell placed in very salty water?
O A. It would stay the same size because salt cannot cross the cell
membrane.
B. It would swell and burst as water moves into the cell, where there
is a higher concentration of water.
C. It would swell and burst because salt would be transported across
the cell membrane.
O D. It would shrink as water moves out of the cell to where there is a
lower concentration of water.
What is full ground state electron configuration of C-?
Answer:
[tex]1s^{2}[/tex] [tex]2s^{2}[/tex] [tex]2p^{2}[/tex]
Explanation:
Simply [tex]1s^{2}[/tex] [tex]2s^{2}[/tex] [tex]2p^{2}[/tex]
Coal has two valent electrons, so there is 2 in 2p orbital
