Answer:
immiscible liquids
Explanation:
When two liquids are to be used for the purpose of recrystallization the both liquids must be miscible with each other in all proportions.
This implies that, if two liquids are immiscible, it will be difficult for the mixture to be useful in recrystallization.
Water and hexane are immiscible because water is a polar solvent and hexane is a non polar solvent.
Water is miscible with ethanol because ethanol contains polar -OH groups that interact effectively with water leading to miscibility of ethanol with water in all proportions.
Object A has a mass of 12g and a volume of 8cm3. object B has a mass of 20g and a volume of 8cm3 . which object has a greater density and by how much
Answer:
Object B has a density of 2.5 g/cm³ which is greater than object A by 1 g/cm³
Explanation:
Since we know that the formula for density is d=m/v, we can divide each mass by its corresponding volume to find the densities
12/8=1.5
20/8=2.5
So we know that object B has a greater density than object A by 1 g/cm³ (gram per cubic centimeter). Also the standard unit for density is kilograms per cubic meter but I used gram per cubic centimeter since they were the given units. 1cm=100m, 1000g=1km
The heat of vaporization for benzaldehyde is 48.8 kJ/mol, and its normal boiling point is 451.0 K. Use this information to determine benzaldehyde’s vapor pressure (in torr) at 53.5°C. Report your answer to three significant digits.
Answer:
[tex]p_2=5.17torr[/tex]
Explanation:
Hello.
In this case, by using the Clausius-Clapeyron Equation which allows us to relate the vapor pressure, temperature and heat of vaporization as shown below:
[tex]ln(\frac{p_1}{p_2} )=\frac{\Delta _vH}{R}(\frac{1}{T_2}-\frac{1}{T_1} )[/tex]
Whereas [tex]p_1[/tex] is 760 torr due to the normal conditions. In such a way, for computing the vapor pressure of benzaldehyde at 53.5 °C (326.65 K), we proceed as shown below:
[tex]\frac{p_1}{p_2} =exp[\frac{48800J/mol}{8.314\frac{J}{mol*K}}(\frac{1}{326.65K}-\frac{1}{451.0K} )]\\\\\frac{p_1}{p_2}=147.0[/tex]
Thus, the vapor pressure at the final T is:
[tex]p_2=\frac{p_1}{147.0}=\frac{760torr}{147.0}\\ \\p_2=5.17torr[/tex]
Best regards!
Calculate the equilibrium concentration of H3O in the solution if the initial concentration of C6H5COOH is 0.056 M . Express your answer using two significant figures.
Answer:
1.9 × 10⁻³ M
Explanation:
Step 1: Write the acid ionization of benzoic acid
C₆H₅COOH(aq) + H₂O(l) ⇄ C₆H₅COO⁻(aq) + H₃O⁺(aq)
Step 2: Calculate the acid ionization constant (Ka) of benzoic acid
The pKa of benzoic acid is 4.20
pKa = -log Ka
Ka = antilog -pKa = antilog -4.20 = 6.31 × 10⁻⁵
Step 3: Calculate the equilibrium concentration of the hydronium ion
Considering that the initial concentration of the benzoic acid is Ca = 0.056 M, we can calculate the equilibrium concentration of the hydronium ion using the following expression.
[H₃O⁺] = √(Ca × Ka) = √(0.056 × 6.31 × 10⁻⁵) = 1.9 × 10⁻³ M
Find the volume of an object that has a density 0f 3.14g/mL and a mass of 87.3g
Answer:
The answer is 27.80 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\ [/tex]
From the question
mass = 87.3 g
density = 3.14 g/mL
We have
[tex]volume = \frac{87.3}{3.14} \\ = 27.8025477...[/tex]
We have the final answer as
27.80 mLHope this helps you
A cell must work to maintain a stable internal environment. It is also important for the environment around the cell to be stable. What reasoning explains what happens when the concentration of water inside a cell is lower than the concentration of water outside the cell?
The cell loses nutrients.
The cell splits and creates two new cells.
The cell gains too many lipids and carbohydrates.
The cell either loses water and dries up or gains too much water and bursts.
(science 7th grade)
Answer: the last one
Explanation: if a cell has too little water, it will begin to function incorrectly, and if a cell has too much water it will burst.
1. How does thermal energy move between objects?
A. It moves from objects of lower mass to objects with higher mass
B. It moves from objects of higher mass to object with lower mass
C. It moves from objects of lower temperature to objects with higher temperature
D. It moves from objects of higher temperatures to objects with lower temperature
Answer:
D
Explanation:
Answer:
D
Explanation:
So. Radiation happens when heat moves as energy waves, called infrared waves, directly from its source to something else.... When the heat waves hits the cooler thing, they make the molecules of the cooler object speed up.
What is chemical energy? (2 points)
a
Energy that is stored or released during a chemical reaction
b
Energy that is destroyed during a physical change
c
Energy that is released during a phase change
d
Energy that is created when a substance is being burned
Answer: a
Energy that is stored or released during a chemical reaction
Explanation: a battery has chemical energy when u but in something that u can power with batteries it starts a chemical reaction.
Hope I helped :)
Explanation:
Chemical energy
Chemical energy is energy stored in the bonds of chemical compounds, like atoms and molecules. This energy is released when a chemical reaction takes place.
Usually, once chemical energy has been released from a substance, that substance is transformed into a completely new substance.
Is Kool-Aid dissolved in water in element compound or mixture?
Answer:
mixture
Explanation:
Kool-Aid is a mixture of sugar, water, dye, and flavoring.
What type of wave does not need matter to carry energy?
The answer is Electromagnetic
Answer:
Electromagnetic
Explanation:
Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.
1) Why does polysubstitution frequently occur with Friedel-Crafts alkylation but not with Friedel-Crafts acylation?2) If Benzene is reacted with t-butyl chloride, why is the chief disubstituted product the para rather than ortho isomer?
Answer:
See explanation
Explanation:
Friedel-Crafts alkylation frequently undergo polysubstitution because the process leads to the addition of an electron donating alkyl group, which activates the benzene ring to further alkylation. The acyl group rather deactivates the ring towards electrophilic substitution.
When benzene is reacted with t-butyl chloride, the chief disubstituted product is the para rather than ortho isomer because the increased bulk of the tert-butyl group hinders attack at the ortho-sites.
A 500. mL gas sample is collected over water at a pressure of 740 mmHg and 25.0 °C. What is the volume of the dry gas at STP?
Answer:
Volume of dry gas at STP = 0.432 liters or 432 ml
Explanation:
Given:
Pressure (P) = 740 mmHg - 24 mmHg = 716 mmHg
Temperature (t) = 25 degrees C + 273 K = 298 K
500 ml = 0.5 l
Find:
Volume of dry gas at STP
Computation:
[P1][V1] / T1 = [P2][V2] / T2
[716][0.5] / 298 K = [760][ x Liters] / 273 K
x = 0.432 Liters
Volume of dry gas at STP = 0.432 liters or 432 ml
Which of the following is one way creativity can help scientists?
By ensuring they follow the scientific method
By increasing the amount of time it takes to complete scientific experiments
By making sure they only try things that have already been proven
By leading them to ask more questions about the natural world
Answer:
Creativity can help scientists by leading them to ask more questions about the natural world.
Explanation:
Beacause they use creativity to make up questions about the natural world.
HELP HELP
why are more common bone fractures among senior citizens than among young people
What is the name???????
Answer:
Carbon Hydrogen
Explanation:
I believe it means carbon (C) to one atom of hydrogen (H).
Now
Selec
BI
Toda
OOOOOO
How and why do ionic bonds form? Check all of the boxes that apply
lonic bonds form between metal atoms and other metal atoms.
Ionic bonds form between metal atoms and nonmetal atoms
The more electronegative atoms transfer one or more electrons to the less electronegative atom
The less electronegative atoms transfers one or more electrons to the more electronegative atom,
The metal atom forms a cation and the nonmetal atom forms an anion
The attraction between ions with the same charge forms an ionic bond,
The attraction between ions with an opposite charge forms an ionic bond.
BLO
I lo
DONE
Elo
Yous
Answer:
✔️Ionic bonds form between metal atoms and nonmetal atoms.
✔️The less electronegative atoms transfers one or more electrons to the more electronegative atom
✔️The metal atom forms a cation and the nonmetal atom forms an anion.
✔️The attraction between ions with an opposite charge forms an ionic bond.
Explanation:
Ionic bond refers to the bond formation which occurs when there is complete and permanent transfer of electrons from one metal atom to another non-metal atom. The metals, which are electropositive (less electronegative) loose their electrons while the non-metals, which are less electropositive (more electronegative) gain the electrons.
When the metal atom looses electrons, they form cations(become positively charged) while non-metal atom forms anions (become negatively charged). When the opposite charges attract each other, they form ionic bond.
Answer:
✔️ Ionic bonds form between metal atoms and nonmetal atoms.
✔️ The less electronegative atoms transfers one or more electrons to the more electronegative atom.
✔️ The metal atom forms a cation and the nonmetal atom forms an anion.
✔️ The attraction between ions with an opposite charge forms an ionic bond.
How many distinct dichlorination products can result when isobutane is subjected to free radical chlorination?
a. 1
b. 2
c. 3
d. 4
e. 6
Answer:
c. 3
Explanation:
Dicholorination of tertiary alkane ( i.e. isobutane) is a halogenation reaction which makes it possible to replace the alkyl functional group with halogenated chlorine.
When Isobutane is subjected to free radicals chlorination, three distinct dichlorination can be formed.
The mechanism of the formation of these products can be seen in the image attached below.
Can you guys answer question 4 on new substance for Chemistry tysm
The answer is a bevasue it then becomes a chemical compound
Answer:
a
Explanation:
this would result in a compound and compounds are chemical changes so i think im right....
Which main type of sedimentary rock forms from solutions?
chemical
clastic
organic
shale
Answer:
The answer is a.
Explanation:
I took the quiz and took notes.
If your questions were the same as mine the answers would be below
Question 1: Which process moves small rock pieces during sedimentary rock formation?
Answer: erosion
------------------------------------
Question 2: Which statement describes one role of minerals during cementation?
Answer: Minerals bind sediments together.
------------------------------------
Question 3: Which correctly lists three factors that contribute to weathering of rock?
Answer: ice, water, wind
------------------------------------
Question 4: The picture shows a sedimentary rock that was formed from crystalized minerals. This is the picture in text form - Orangish red rock with coarse texture.
Actual question number 4: Which type of sedimentary rock is shown?
Answer: chemical
------------------------------------
Question 5: Which type of sedimentary rock forms from weathered sediment?
Answer: clastic
------------------------------------
Question 6: Which statement describes deposition?
Answer: Deposition happens after weathering and erosion.
------------------------------------
Question 7: Which correctly lists three agents that loosen and carry away rock during the erosion process?
Answer: plants, animals, wind
------------------------------------
Question 8: Which processes contribute to the formation of chemical sedimentary rocks?
Answer: Minerals dissolve and crystalize.
------------------------------------
Question 9: The image shows an example of a sedimentary rock. This is the picture in text form - Brown rock containing small pieces of different materials.
Actual question: Which feature of this rock demonstrates that it is a clastic sedimentary rock?
Answer: visible rock fragments
------------------------------------
Question 10: Which process squeezes layers of sediment together?
Answer: compaction
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Pictures used in question four and question nine are in the attached pictures.
God bless! :D
Photosynthesis
Definition in youre own words? thank you<3
Answer:
the process of plants taking the sunlight and turning it into food for the plant.
Explanation:
Pls, Help ASAP with 30 points!!!
Describe the similarities and differences between the eruptions of
less gassy and more gassy magma.
Answer:
the difference is tyat eruptions of less gassy and more gassy is that the less gassy doesnt retain as much gas as the more gassy one and thus the eruption of the less gassy is less damage to the more gassy
You make up a solution of a diprotic acid, H2A, having pKa values of 5.0 and 9.0. Identify the primary, secondary, and tertiary species when you set the pH equal to 8.0 by addition of KOH.
Answer:
Explanation:
A solution with a pH value of 7 is neutral i.e neither acidic nor alkaline. A solution with a pH less than 7 is said to be acidic, while one with a pH value more than 7 is alkaline. Acidity increases as the value decrease below 7, while alkalinity increases as the value increase about 7.
Given that H2A is a diprotic weak acid have pKa values of 5.0 ad 9.0, it will undergo dissociation in the solution as:
NOTE: These reactions are reversible reactions.
[tex]\mathbf{H_2A \to H^+ + HA^- \ \ \ pKa = 5.0}[/tex]
[tex]\mathbf{HA^- \to H^+ +A^{2-} \ \ \ pKa = 9.0}[/tex]
Thus;
The primary species is HA⁻
The secondary species is A²⁻
Which factor is most important to keep the same when looking at the
meniscus to compare the surface tension of different liquids?
A. The intensity of light
B. Type of container
C. Temperature
D. Type of material
Answer:
b. the type of container
Explanation:
Answer:
The type of container
Explanation:
Just took the test
Literally struggling with this concept.(problem set included below)
Which statement describes the effect of sorting and recombining genes in sexual reproduction?
Group of answer choices
offspring receive only recessive genes
offspring receive only dominant genes
offspring receive the same set of genes
offspring receive a unique combination of genes
2. Why would a calcium (Ca) atom be larger than a bromine (Br) atom even
though they both have 4 energy levels? *
Within a period, the atom size decreases with increasing group number (from left to right), since the nuclear charge and the number of external electrons increase within the period, but the number of shells does not. The electrons are more strongly attracted to the nucleus and are therefore closer to the nucleus.
describe the structure and function of gamma rays
Answer:
A gamma ray is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves and gives off the highest photon energy. The energy spectrum of gamma rays can be used to identify the decaying radionuclides using gamma spectroscopy.
Explanation:
The osmotic pressure exerted by a solution is equal to the molarity multiplied by the absolute temperature and the gas constant . Suppose the osmotic pressure of a certain solution is measured to be at an absolute temperature of . Write an equation that will let you calculate the molarity of this solution. Your equation should contain only symbols. Be sure you define each symbol other than . Your equation: Definitions of your symbols:
Answer:
c = π / R × T
Explanation:
The osmotic pressure exerted by a solution is equal to the molarity multiplied by the absolute temperature and the gas constant R . Suppose the osmotic pressure of a certain solution is measured to be 22 atm at an absolute temperature of 353 K. Write an equation that will let you calculate the molarity c of this solution. Your equation should contain only symbols. Be sure you define each symbol other than R.
Step 1: Given data and definition of the symbols
Osmotic pressure (π): 2.2 atmMolarity of the solution (c): ?Ideal gas constant (R): 0.08206 atm.L/mol.KAbsolute temperature (T): 353 KStep 2: Write an equation that will let you calculate the molarity of this solution, in terms of symbols
The osmotic pressure is a colligative property that can be calculated using the following expression.
π = c × R × T
We can rearrange this expression to calculate the molarity of the solution.
c = π / R × T
Determine the pH of a 0.461 M C6H5CO2H M solution if the Ka of C6H5CO2H is 6.5 x 10-5. Determine the pH of a 0.461 M C6H5CO2H M solution if the Ka of C6H5CO2H is 6.5 x 10-5. 11.74 9.48 5.48 4.52 2.26
Answer:
the answer
Explanation:
the answer
The pH of the solution can be calculated using the Ka value and molarity of the acid. pH of the acid is obtained as 2.26.
What is pH?pH of a solution is the measure of acidity or basicity. Mathematically it is the negative logarithm of H+ ion concentration in the solution.
pH = - log [H+]
The constant Ka is called ionization constant of an acid. Acetic acid ionizes into equimolar concentrations of H+ and CH₃COO- ions. The Ka can be written as:
[tex]\rm K_{a} = \frac{[CH_{3}COO^{-}][H+]}{[CH_{3}COOH]}[/tex]
Where, [CH₃COO-] = [H+] Thus the expression becomes changed and from the values of Ka and molarity of the acid, H+ ion concentration can be calculated.
6.5 × 10⁻⁵ = [H+]² / [0.461 M]
[H+] = 0.0054.
Now, the pH can be calculated as follows:
pH = - log [0.0054]
= 2.26.
Therefore, the pH of the acidic solution is 2.26.
To find more on pH, refer here:
https://brainly.com/question/491373
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The pair of elements with the most familiar chemical properties are
A. Mg and S
B. Ca and Br
C. Mg and Ca
D. S and Ar
Answer:
C. mg and Ca
Explanation:
These chemical elements are collectively called as the Alkaline Earth Metals. Calcium and Magnesium are two of the six elements that fall into this category. The outer electronic structure of all these elements is similar due to which they all have similarity in their chemical and physical properties. They are all shiny, though fairly soft but still harder than alkali metals. Further, these are usually white or silvery coloured elements.They react with water to form hydrogen gas and metal hydroxide and with oxygen, they form oxides.
What stress causes this type of fault to form? O compression O gravity O tension O shearing
Answer: It’s D
Explanation:
Cuz I said so
Answer: d. Shearing
Explanation: