Answer:
Hope this will help.......
Explanation Covalent bonds are insoluble in water (H2O) , but covalent compounds are. This is because some organic compounds (covalent) contain the polar −OH group which can bond to a hydrogen ion to form water.
True or false. (Pls help)
Answer:
1.) False?
2.) true. sorry english not my first language
What pressure is required to compress 200 liters of air at 100 atmosphere into a
cylinder whose volume is 20.0 liters?
Answer:
P₂ = 1000 atm
Explanation:
Given data:
Initial volume of air = 200 L
Initial pressure = 100 atm
Final volume = 20.0 L
Final pressure required = ?
Solution:
The given problem will be solved through the Boly's law,
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
100 atm × 200 L= P₂ × 20.0 L
P₂ = 20,000 atm. L/ 20.0 L
P₂ = 1000 atm
Practitioners of the branch of alternative medicine known as homeopathy claim that very dilute solutions of substances can have an effect. Is the claim plausible? To explore this question, suppose that you prepare a solution of a supposedly active substance, X, with a molarity of 0.10 molL1 . Then you dilute 10. mL of that solution by doubling the volume, doubling it again, and so on, for 90 doublings in all. How many molecules of X will be present in 10. mL of the fi nal solution? Comment on the possible health benefi ts of the solution.
Answer:
a. 4.865 × 10⁻⁷ molecules. b. The possible health benefits of the drug might be minimal or non-existent.
Explanation:
a. Since we have 0.10 mol/L and 10 mL of solution, the number of moles in 10 mL of solution is n = CV where C = concentration and V = Volume. C = 0.10 mol/L and V = 10 mL = 0.01 L.
So n = CV = 0.10 mol/L × 0.01 L = 0.001 mol.
Since the initial volume of the solution is 10 mL and doubled, it is 2 × 10 mL = 20 mL. It is doubled again to 2 × 20 mL = 40 mL. It is doubled again to 2 × 40 mL = 80 mL. Our third doubling is thus 80 mL = 2 × 2 × 2 × 10 mL = 2³ × 10 mL. So the volume for our nth doubling is V = 2ⁿ × 10 mL. So four our 90 th doubling, the volume is V = 2⁹⁰ × 10 mL = 2⁹⁰ × 10 mL
Since we have 0.001 mol present, the concentration in this new volume is thus C' = 0.001 mol/2⁹⁰ × 10 mL.
So the number of moles in 10 mL of this solution is thus n = 0.001 mol/(2⁹⁰ × 10 mL) × 10 mL = 0.001/2⁹⁰ mol
To find the number of molecules of X present we use, number of moles, n = number of molecules, N/Avogadro's number of molecules, N'
n = N/N'
N = nN'
= 0.001/2⁹⁰ mol × 6.022 × 10²³ molecules/mol
= 8.078 × 10⁻³¹ × 6.022 × 10²³
= 48.65 × 10⁻⁸
= 4.865 × 10⁻⁷ molecules.
b. Since the number of molecules of X present in 10 mL solution of the final diluted solution is 4.865 × 10⁻⁷ molecules, this shows that the number of molecules of X is very little so, the possible health benefits of the drug might be minimal or non-existent.
Down a group, the electron shielding tends to________
a.)increase
b.)decrease
thank uuu :)
Answer:
A
Explanation The number of energy levels (n) increases, and so does the distance between the nucleus and the outermost orbital. The increased distance and the increased shielding weaken the nuclear attraction, and so an atom can't attract electrons as strongly.
Someone knows how to solve this? It was found that 0.0005 mol of Ca (OH) 2 dissolved in 100 cm3 of solution is 80% dissociated. Calculate the pH of this solution.
Answer:
pH = 11.9
Explanation:
First, we determine the number of OH⁻ moles dissolved:
80% of Ca(OH)₂ is dissolved:
0.0005 mol * 80/100 = 4x10⁻⁴ mol Ca(OH)₂There are two OH⁻ moles per Ca(OH)₂ mol:
4x10⁻⁴ * 2 = 8x10⁻⁴ mol OH⁻Now we can calculate the molar concentration of OH⁻ (moles/L):
100 cm³ = 100 mL100 mL ⇒ 100/1000 = 0.1 L[OH⁻] = 8x10⁻⁴ mol / 0.1 L = 8x10⁻³ MThen we calculate the pOH of the solution:
pOH = -log[OH⁻] = -log(8x10⁻³ M) = 2.10Finally, we can calculate the pH of the solution using the equation
pH + pOH = 14pH = 14 - pOH = 14 -2.10pH = 11.9Calculate the gravitational force between two objects when they are 0.75m apart each object has a mass of 5.00kg
Answer:
0.000000000666863
Explanation:
F = GMm/R²
The second atomic structure YES
No
Answer
The second part of the theory says all atoms of a given element are identical in mass and properties. The third part says compounds are combinations of two or more different types of atoms. The fourth part of the theory states that a chemical reaction is a rearrangement of atoms.
Explanation:
how many moles of sulphur are in 53.7 grams of sulphur
Answer:
1.67 mol S
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisExplanation:
Step 1: Define
53.7 g S
Step 2: Define Conversions
Molar Mass of S - 32.07 g/mol
Step 3: Convert
[tex]53.7 \ g \ S(\frac{1 \ mol \ S}{32.07 \ g \ S} )[/tex] = 1.67466 mol S
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
1.67466 mol S ≈ 1.67 mol S
Why are ions usually formed during the interaction of metal with nonmetal and not between two metals?
Explanation:
Ions are always formed when metals and non-metals interact because metals are electropositive. They willing release electrons to non-metals that are electronegative.
This activity results in charge separation. The transfer of electrons from one specie to another is what results in an ionic bond and the precedence of charged particles.
Between non-metals, the electrons are jointly shared. Therefore, there is no charge separation.
The theory of plate tectonics was, at first, rejected by most scientists. Now most geologists accept that tectonic plates exist and that these tectonic plates can and do move. What is responsible for the change in how scientists think about plate tectonics?
Answer:
The validation of seafloor spreading in the 1950s and 60s
Explanation:
The theory of seafloor spreading was supported by numerous evidence including thermal probes that showed that heat flow over the mid-ocean ridges measured up to four times those measured in general bottom sediments, which are taken as due to the presence of molten Earth material close to the ridge crest
The ridge crest also show signs unusually seismic wave velocities that are considered to be due to microfracturing and thermal expansion from upwelling magma
What is the correct name for the following compound: P2Br5
Answer:
Diphosphorus pentabromide is the official name.
Explanation:
Sucrose is an organic compound made by plants for quick energy. What type of organic compound is sucrose?
1-protein
2-carbohydrate
3-lipid
4-nucleic acid
Answer:
2-carbohydrate
Explanation:
Sucrose belongs to the carbohydrate family. It is a disaccharide which is derived from the condensation of glucose and fructose.
In the body, they are sources of energy for living processes. Upon hydrolysis such disaccharide produces tow monosaccharide units. Food substances that are energy rich will contain some of these organic molecules.Sucrose is a specific type of organic compound classified as a carbohydrate and the correct option is option 2.
Carbohydrates are essential biomolecules made up of carbon, hydrogen, and oxygen atoms. Sucrose, also known as table sugar, is a disaccharide formed by the chemical bonding of one glucose molecule and one fructose molecule.
Plants produce sucrose through photosynthesis and use it as a readily available source of energy. When consumed by animals, including humans, sucrose is broken down into its constituent monosaccharides to provide fuel for various cellular processes.
Thus, the ideal selection is option 2.
Learn more about Carbohydrates, here:
https://brainly.com/question/33874241
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What kind of molecule can experience hydrogen bonding?
A. A nonpolar molecule containing a hydrogen atom
B. A molecule with hydrogen bonded to any nonmetal
C. A molecule with hydrogen bonded to O, N, or F
D. Any polar molecule containing a hydrogen atom
Answer:
Answer is C
Explanation:
C - A molecule with hydrogen bonded to O, N, or F
A molecule with hydrogen bonded to O, N, or F can experience hydrogen bonding. Therefore, the correct option is option C.
A hydrogen atom is attracted to another electronegative atom in a neighbouring molecule when it is connected to a strongly electronegative atom (O, N, or F). This attraction is more powerful than the usual dipole-dipole interactions between polar molecules.
The enormous electronegativity differential between hydrogen and the highly electronegative atom causes hydrogen bonding. The electronegative atom attracts the shared electrons in the covalent link, causing the hydrogen atom to gain a partial positive charge.
To know more about hydrogen bonding, here:
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How does more greenhouse gases in the Earth's atmosphere affect earth's temperature?
Explanation:
Greenhouse gasses in Earth's atmosphere affect Earth's temperature by making it hotter. Greenhouse gasses make the Earth warmer by trapping heat. You can think of greenhouse gasses as Earth's blanket.
Answer:
It effects the earth when we have more greenhouse gasses in the earth's atmosphere because it makes the earth more warmer which will cause more sunlight to hit earth because there is more heat near the earth's surface, and this will cause the temperatures to rise really high because of the heat.
Hope this helps!
how can you find the Frequency if you only have the wavelength? can you solve this example what is the Frequency of the wavelength 4km? can you please show your steps thanks.
Answer:
75000 Hz
Explanation:
f = V / λ (f= frequency, v=velocity of wave, lambda= wavelength)
alternatively, f = c / λ (f= frequency, c= speed of light- 3.00x10^8 m/s, lambda= wavelength)
f= [3.00x10^8 m/s]/[4000 m]
=75000 Hz
Unlike particles in a liquid or a gas, the particles in a typical solid are arranged
A. separately from one another in constantly changing positions
B. in close contact with one another and in constantly changing positions
C. randomly in fixed positions
D. in orderly patterns and fixed positions
Answer:
D. In orderly patterns and fized positions
Explanation:
which of the metal is suitable to store lead nitrate solution
Explanation:
The nitrate anion is a univalent (-1 charge) polyatomic ion composed of a single nitrogen atom ionically bound to three oxygen atoms (Symbol: NO3) for a total formula weight of 62.05. Lead Nitrate is generally immediately available in most volumes.
is this correct? and can you tell me yes or no for each one thanks
Answer: Yes it's correct.
Explanation: i hoped that helped!!
Answer:
yes this is correctly done
PLEASE HELP ME!!!
THE CHEM QUESTION IS...
Calculate the amounts of heat required for 25.0 g of water to change from 10°C to 30°C
Answer:
1045
Answer: 1045 J of energy was released on cooling the down the water from 20 °C to 10 °C.
Answer:
..............=2100
Please answer it!! Would appreciate it!
[tex] \sf \: Answer \: 8 \: :[/tex]
→ During the formation of a chemical bond, heat is released.
[tex] \sf \: Answer \: 9 \: :[/tex]
→ Solution that contains all the solute it can hold at a given temperature is saturated.
[tex] \sf \: Answer \: 10\: :[/tex]
→ No. of neutrons present in Bromine are 44
What is the overall charge of the compound, NaF?
+2
-2
-1
0
Answer: -1
Explanation: It is neutral because the Na and F atoms are transferring their valence electrons in order to become stable. This results in an overall stable atom. If we were to identify the individual charges of verbalized atoms, Na would have a positive charge, and F a negative charge - both of 1.
It's not -1.
the answer is (0), hope this helped
What percent of a human cell is made of macromolecules?
Answer:
About 70 percent. I hope this helps :)
Which molecule has the strongest forces of attraction between molecules?
Dipole-dipole interactions are the strongest intermolecular pressure of attraction.
Answer: Dipole-dipole interactions are the strongest intermolecular force of attraction.
Explanation:
help !!!!!!! cell membrane plants information due soon
What were some dangers associated with early ballon flights?
Explanation:
The dangers of ballooning were apparent to aeronauts and the general public. From the early 1800s, attempts to fly over water too often ended in disaster or a narrow escape. Some of the best known aeronauts on both sides of the Atlantic set off across a large body of water never to be seen again.
Which of the following is an example of Newton’s 2nd Law? A. A bowling ball requires more force to roll than a tennis ball B. Sitting in a chair C. A rocket blasting off D. All of the above
Answer:
The answer is A.
Explanation:
When is evaporation used
before the water goes back in the enviorment
Based on the given information, which of the following is the students' correct conclusion about their experiment?
Answer:kj
Explanation:nnn
A teacher showed this animal to students on a field trip which tool will allow the students to best see the animal up close
Answer:
Magnify glass
What does it mean when a compound is 'soluble in water?
A. It does not dissolve in water.
OB. It dissolves in water.
O C. It forms a precipitate in water.
O D. It has water molecules attached to it.
B. It dissolves in water.
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Answer:
B it dissolves in water
Explanation:
Their molecules bond to water molecules