Answer:
To start, you need know that all a mole means is you have 6.022 x 1023 atoms of that type. So if I tell you I have a mole of nitrogen, then I have 6.022 x1023 nitrogen atoms. That ugly number is called Avogadro's Constant, NA
Explanation:
hy its isnt the correct answer but checkout the equation hope it help help
g Determine the percent enantiomeric excess of a sample with specific rotation of 14 compared to an enantiomerically pure reference stereoisomer of the sample that has specific rotation -24
Answer:
Explanation:
Enantiomeric excess of this compound X is given by the formula
EE= Observed specific rotation*100 / maximum specific rotation
EE= 14*100/24 = 58.33%
Percentage enantiomeric excess
%(-) = EE/2 +50
= 58.33/2 + 50
= 79.12% OF (-)X and 20.88% of (+) X
A given sample of a gas has a volume of 3.0 L at a pressure of 4.0 atm. If the temperature remains constant and the pressure is Changed to 6.0 atm, why is the new volume?
Answer:
2L
Explanation:
P1xV1=P2xV2
P1=4 atm
V1=3L
P2=6 atm
V2= ?
V2= (4 x 3)/ 6
V2=2L
Enter your answer in the provided box. Find the pH of a buffer that consists of 0.31 M boric acid (H3BO3) and 0.36 M sodium borate (NaH2BO3). (pKa of boric acid
Answer:
pH = 9.30
Explanation:
We can obtain the pH of a buffer using H-H equation:
pH = pKa + log [A⁻] / [HA]
Where pH is the pH of the solution,
pKa the pKa of the buffer (9.24 for boric acid)
[A⁻] the molarity of the conjugate base, NaH2BO3
[HA] molarity of the weak acid, H3BO3
Replacing:
pH = 9.24 + log [0.36M] / [0.31M]
pH = 9.30
Which susbatances are combinations of nonmetals
Why do you think it’s important to follow the steps of the scientific method?
i think science is important bcoz it has a choice whether to save or not
like now scientist are finding a cure for corona
What kind of bond would two nonmetals typically make?
A. An ionic bond
B. A covalent bond
C. A metallic bond
D. An ionic solid
Answer:
covalent bond
Explanation:
which two body systems work together to deliever oxygen to the cells
Answer:
circulatory and respiratory
Explanation:
your welcome :)
A 200. g piece of metal is boiled in ethanol for 3 minutes and then transferred to a styrofoam cup containing 250. mL of water at 23 C. The metal and water are allowed to come to thermal equilibrium at a temperature of 27.5 C. If ethanol boils at a temperature of 78 C:
a. What is the delta T for the metal
b. What is the delta T for the water
c. what is the specific heat capacity for the unknown metal?
ΔT for the metal = 50.5 °C
ΔT for the water = 4.5 °C
The specific heat capacity for the unknown metal : 0.466 J/g° C
Further explanationThe law of conservation of energy can be applied to heat changes, i.e. the heat received/absorbed is the same as the heat released
Q in = Q out
Heat can be calculated using the formula:
Q = mc∆T
Q = heat, J
m = mass, g
c = specific heat, joules / g ° C
∆T = temperature difference, ° C / K
A 200. g piece of metal is boiled in ethanol (boiling point: 78 C), so :
m metal = 200 g
Ti metal(initial temperature of metal)=78 C
T(system temperature at equilibrium)=27.5
m water = 250 ml x 1 g/ml = 250 g
c water = 4.18 joules / g ° C
Tiw(initial temperature of water) = 23
a. ΔT metal[tex]\tt 78-27.5=50.5^oC[/tex]
b. ΔT water[tex]\tt 27.5-23=4.5^oC[/tex]
c. the specific heat capacity for the unknown metal[tex]\tt Q~metal=Q~water\\\\200\times c\times (78-27.5)=250\times 4.18\times (27.5-23)\\\\10100\times c=4702.5\\\\c=0.466~J/g^oC[/tex]
Squalene, an important intermediate in the biosynthesis of steroids, has the molecular formula C30H50 and has no triple bonds. (a) What is the index of hydrogen deficiency of squalene
Answer:
6
Explanation:
Molecular Formular = C30H50
Degree of saturation = (2C + 2 - H ) / 2
Degree of saturation = [ 2(30) + 2 - 50 ] / 2
Degree of saturation = ( 62 -50 ) / 2 = 12 / 2 = 6
Which of the following has an (S) Configuration
Answer:
As opposed to this, if the arrow goes counterclockwise then the absolute configuration is S.
Explanation:
A sample has a nitrate concentration of 4.39 mg/L (4.39 ppm nitrate). Calculate its molar concentration (in moles/L). (This primarily involves unit conversions).
Answer:
[tex]0.0000708\ \text{mol/L}[/tex]
Explanation:
The nitrate concentration of the sample = [tex]4.39\ \text{mg/L}=4.39\times 10^{-3}\ \text{g/L}[/tex]
Molar mass of [tex]NO^-_3=62.0049\ \text{g/mol}[/tex]
The molar concentration is obtained when we divide the concentration by its molar mass in the approriate units.
[tex]\dfrac{4.39\times 10^{-3}}{62.0049}=0.0000708\ \text{mol/L}[/tex]
The molar concentration is [tex]0.0000708\ \text{mol/L}[/tex]
convert 3.01•10^23 molecules of C2H6 to moles.
Answer:
The answer is 0.5 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\ [/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
[tex]n = \frac{3.01 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{3.01}{6.02} \\ [/tex]
We have the final answer as
0.5 molesHope this helps you
I miss school for personal reasons and now im back and i don’t understand anything please help i dont want to fail
Answer:
E = 2.80×10⁻¹⁶ j
E = 5.37×10⁻¹⁷j
Explanation:
Given data:
Frequency of photon = 4.23 ×10¹⁷ Hz
Energy of photon = ?
Solution:
Formula:
E = h× f
E = 6.63×10⁻³⁴ js ×4.23 ×10¹⁷ Hz
Hz = s⁻¹
E = 28.0×10⁻¹⁷ j
E = 2.80×10⁻¹⁶ j
2)
Given data:
Frequency of photon = 8.10×10¹⁶ Hz
Energy of photon = ?
Solution:
E = h× f
E = 6.63×10⁻³⁴ js × 8.10×10¹⁶ Hz
Hz = s⁻¹
E = 53.7×10⁻¹⁸j
E = 5.37×10⁻¹⁷j
The image on the left shows the charges on a balloon after it’s been rubbed with a wool cloth. The image on the right is a piece of tissue paper. What will happen to the tissue paper as it approaches the balloon and why?
Answer:
B = tissue paper will stick to the balloon because it is positively charged.
Explanation:
The option B is correct. Balloon is negatively charged while it is stated in question and can also see from the picture tissue paper is positively charged.
We know that opposite charges attract each other. Thus when balloon and tissue paper come close to each other the stick together.
All other options are incorrect because,
Option A:
In option it is stated that tissue paper is negatively charged. Although negative charges are present but there is more positive charge in balloon we can say that more number of protons are present thus balloon have positive charge.
Option C:
Tissue paper is negatively charged and will move away.
It is wrong. Tissue paper is positively charged.
Option D:
Tissue paper will move away because it is positively charged. It is also wrong statement because tissue paper will not move away it will stick to the balloon because of positive charge.
Describe how your response in the previous question explain the decrease in the temperature measured during the evaporation process
Answer:
See explanation
Explanation:
Evaporation is an endothermic process. In an endothermic process, heat is absorbed from the surrounding. This causes the system to feel cool.
Since evaporation is endothermic and heat is absorbed from the surrounding, the system will feel cool and the temperature of the system decreases accordingly.
Hence, during evaporation, the temperature of the system decreases.
When 0.627 g of biphenyl (CH) combusts in a bomb calorimeter, the temperature rises from 21.9 C to 26.6 C. What is U for the reaction in kJ/mol biphenyl
Answer:
[tex]U=-6852\frac{kJ}{mol}[/tex]
Explanation:
Hello there!
In this case, since the heat capacity of the bomb calorimeter, we can use this found value on ethernet: 5.86 kJ/°C, thus, we can compute the heat gained by the calorimeter:
[tex]Q_{calorimeter}=C\Delta T=5.86kJ/\°C*(26.6-21.9)\°C=27.54kJ[/tex]
Thus, since the heat gained by the calorimeter is actually the heat released due to the combustion of byphenyl, we compute it as the negative of that of the calorimeter:
[tex]Q_{combustion}=-Q_{calorimeter}=-27.54kJ[/tex]
Finally the energy of reaction, U, in kJ/mol for the combustion of byphenyl (molar mass = 154 g/mol) is:
[tex]U=\frac{-27.54kJ}{0.627g*\frac{1mol}{156g} } \\\\U=-6852\frac{kJ}{mol}[/tex]
Best regards!
If a 0.775 M solution of a base is found to have a hydroxide concentration of 0.050 M at equilibrium, what is the percent ionization of the base
Answer:
[tex]\%\ ionization=6.45\%[/tex]
Explanation:
Hello.
In this case, since the ionization of a hypothetical base MOH is:
[tex]MOH(aq)\rightleftharpoons M^+(aq)+OH^-(aq)[/tex]
The equilibrium expression is:
[tex]Kb=\frac{[M^+][OH^-]}{[MOH]}[/tex]
And the percent ionization is:
[tex]\%\ ionization=\frac{[OH^-]}{[MOH]} *100\%[/tex]
For the equilibrium concentration of hydroxide, it turns out:
[tex]\%\ ionization=\frac{0.050M}{0.775M}*100\%\\\\\%\ ionization=6.45\%[/tex]
Best regards!
NiCl2 —> Ni + Cl2
What is the type of reaction? Also the reactants and products?
What are the major characteristics of metals
The diagram shows the different models of the atom that eventually led to the modern atomic theory.
Which model represents the current atomic theory based on our knowledge of the nucleus and electron cloud?
1) Model A
2) Model B
3) Model C
4) Model D
The model depicted that has been resembling the modern atomic theory has been Model D. Thus option 4 is correct.
The atom has been the smallest unit of the matter, that has been consisted of the electrons, protons, and neutrons as the subatomic particles.
The modern atomic theory has stated that the structure of the atom has a positively charged centrally located nucleus, with the negatively charged body revolving around it.
The central nucleus has consisted of the neutral neutrons and positive protons, while the revolving bodies have been the negative electrons. The model depicted that has been resembling the modern atomic theory has been Model D. Thus option 4 is correct.
For more information about the modern atomic theory, refer to the link:
https://brainly.com/question/7910610
Answer: Model D; answers 4
Explanation: Is the most modern and recent atom model based on our knowledge.
Butane (C4H10) burns in the presence of oxygen to produce carbon dioxide gas and water vapor. Write a balanced equation for this reaction and calculate the number of liters of carbon dioxide measured at STP that could be produced from 5.69g of butane
Answer:
8.78 L
Explanation:
The balanced equation for the combustion of butane (C₄H₁₀) in presence of oxygen (O₂) to produce carbon dioxide (CO₂) and water (H₂O) is the following:
2C₄H₁₀ + 13O₂ ⇒ 8CO₂ + 10H₂O
First, we calculate the moles there are in 5.69 g of butane, by dividing the mass into the molecular weight (MM butane= 58 g/mol):
moles C₄H₁₀= mass/MM= 5.69 g/(58 g/mol)= 0.098 mol
According to the equation, 2 moles of C₄H₁₀ produce 8 moles of CO₂. Thus, if we have 0.098 moles C₄H₁₀:
moles CO₂= 0.098 mol C₄H₁₀ x 8 mol CO₂/(2 mol C₄H₁₀)= 0.392 mol CO₂
Finally, we know that 1 mole of any gas occupies a volume of 22.4 L measured at STP, so we calculate the volume of CO₂ as follows:
volume CO₂= 0.392 mol CO₂ x 22.4 L/1 mol CO₂= 8.78 L
Reactivity of a_______ depends on how easily an electron(e-) can be removed. (This is lonization energy)
Answer:
1. How is ionization energy related to how easily an electron can be lost from an atom? The easier it is to lose an electron the smaller the amount of energy needed to remove it (smaller ionization energy). ... The amount of positive charge increases as the number of protons increase from left to right across a period.
Explanation:
3. How are the three mutated strands different from each other?
Answer:
Two major categories of mutations are germline mutations and somatic mutations. Germline mutations occur in gametes. These mutations are especially significant because they can be transmitted to offspring and every cell in the offspring will have the mutation. Somatic mutations occur in other cells of the body
Explanation:
g o o g l e
Two major categories of mutations are germline mutations and somatic mutations. Germline mutations occur in gametes.
What is mutation?A mutation is a change to an organism's DNA sequence. Errors in DNA replication during cell division, exposure to mutagens, or viral infection can all cause mutations. Somatic mutations (which happen in body cells) cannot be passed on to offspring, whereas germline mutations (which happen in eggs and sperm) can.
Our cells are constantly undergoing mutations, yet very few of these have any negative effects on our health. Compared to what we typically see in science fiction movies, this is completely different.
A mutation is never so advantageous in real life that it makes someone a superhero or does anything strange like give them wings.
Therefore, Two major categories of mutations are germline mutations and somatic mutations. Germline mutations occur in gametes.
To learn more about gametes, refer to the link:
https://brainly.com/question/2569962
#SPJ2
what is the minimum amount of water is needed to dissolve 3.0 mol potassium dichromate (k2cr2o7)
Answer:
6.79 litres
Explanation:
Potassium dichromate is K2Cr2O7
Its molar mass = 294.18 g/mol
If,
1 mole = 294.18 g
3 mole = 3 x 294.18 g
= 882.54 g
Solubility of K2Cr2O7 is
4.9 g/100 mL at 0⁰c
13 g/100 mL at 20⁰c
102 g/100 mL at 100⁰c
No specific temperature is given so I have used 20⁰C since it is close to room temperature.
at 20⁰C:
13 g of K2Cr2O7 would dissolve in = 100 mL
So 1 g of K2Cr2O7 dissolves in = (100/13)
= 7.692
882.54 g of K2Cr2O7 dissolves in = 882.54 x 7.692
= 6788.59mL
We convert to litres
= 6.79 L
The atomic mass in Phosphorus is a decimal because __________. Neutrons aren't always the same mass. It is charged. proton number varies. It is the average mass of all phosphorus elements in nature.
Answer:
"It is the average mass of all phosphorus elements in nature."
Explanation:
I don't really know why, I just got it right on this quiz with this answer. Hope it helps :)
Match the scientist with his discovery or contribution.
Match Term Definition
J. J. Thomson A) Electrons
John Dalton B) Atoms
Ernest Rutherford C) Neutrons
James Chadwick D) Protons
Answer:
J. J. Thomson - Electrons
John Dalton - Atoms
Ernest Rutherford - Protons
James Chadwick - Neutrons
Answer:
Look at the picture :)
In the titration of a monoprotic acid with a monoprotic base, the point at which the same number of moles of acid and base have been added is called the ______________.
Answer:
The correct approach is "Equivalence point ".
Explanation:
The equivalence point seems to be the exact or actual point at which the chemical compound stops in a combination of titrations. Titration is also conducted to assess a substance's concentration in something like a solution. We would have to utilize a titrant with either a standard solution and can interfere with either the product unless the substance remains established or recognized.What is the formula mass of (NH4)3 PO4? (Show work)
Answer:
Mass = 149g
Explanation:
N3 = 3x14u = 42
H12 = 12x1u = 12
P = 1x31u = 31
O4 = 4x16u = 64
42+12+31+64 = 149g
How many grams of water can be heated from 25.0 C to 35.0 C by the heat released from 85.0 g of iron that cools from 85 C to 35 C
Answer:
31.94 g
Explanation:
Water
ΔT = 35 C - 25 C = 10
m = ?
c = 4.182 J/gC
Heat = mc ΔT
Iron
ΔT = 85 C - 50 C = 35 (Negative sign is not relevant)
m = 85
c = 0.449 J/gC
Heat = mc ΔT= 85 * 0.449 * 35 = 1335.76 J
Substituting the value of heat in the equation for water;
Heat = m * 4.182 * 10
1335.76 = m * 41.82
m = 31.94 g
What is the mass percent of water in nickel(II) sulfate hexahydrate?
The mass percent of water in nickel (II) sulfate hexahydrate is 41.129 %.
The chemical formula of nickel (II) sulfate hexahydrate is NiSO₄.6H₂O.
The mass of 1 mole of NiSO₄.6H₂O is:
[tex]mNiSO_4.6H_2O = mNi + mS + 10mO + 12mH \\= 58.69 g + 32.07 g + 10 \times 16.00 g + 12 \times 1.01 g = 262.88 g[/tex]
The mass of H₂O in 1 mole of NiSO₄.6H₂O is:
[tex]mH_2O = 6 \times (2mH + mO) = 6 \times (2 \times 1.01 g + 16.00 g) = 108.12 g[/tex]
The mass percent of H₂O in NiSO₄.6H₂O is:
[tex]\% H_2O = \frac{mH_2O}{mNiSO_4.6H_2O} \times 100 \% = \frac{108.12 g}{262.88 g} \times 100 \% = 41.129 \%[/tex]
The mass percent of water in nickel (II) sulfate hexahydrate is 41.129 %.
You can learn more about percent composition here: https://brainly.com/question/17505281