Answer:
Double replacement
Explanation:
took notes when learned on edge
Answer:
double replacement
Explanation:
just took test
One kilogram of water at 100 0C is cooled reversibly to 15 0C. Compute the change in entropy. Specific heat of water is 4190 J/Kg.K.
Answer:
The change in entropy is -1083.112 joules per kilogram-Kelvin.
Explanation:
If the water is cooled reversibly with no phase changes, then there is no entropy generation during the entire process. By the Second Law of Thermodynamics, we represent the change of entropy ([tex]s_{2} - s_{1}[/tex]), in joules per gram-Kelvin, by the following model:
[tex]s_{2} - s_{1} = \int\limits^{T_{2}}_{T_{1}} {\frac{dQ}{T} }[/tex]
[tex]s_{2} - s_{1} = m\cdot c_{w} \cdot \int\limits^{T_{2}}_{T_{1}} {\frac{dT}{T} }[/tex]
[tex]s_{2} - s_{1} = m\cdot c_{w} \cdot \ln \frac{T_{2}}{T_{1}}[/tex] (1)
Where:
[tex]m[/tex] - Mass, in kilograms.
[tex]c_{w}[/tex] - Specific heat of water, in joules per kilogram-Kelvin.
[tex]T_{1}[/tex], [tex]T_{2}[/tex] - Initial and final temperatures of water, in Kelvin.
If we know that [tex]m = 1\,kg[/tex], [tex]c_{w} = 4190\,\frac{J}{kg\cdot K}[/tex], [tex]T_{1} = 373.15\,K[/tex] and [tex]T_{2} = 288.15\,K[/tex], then the change in entropy for the entire process is:
[tex]s_{2} - s_{1} = (1\,kg) \cdot \left(4190\,\frac{J}{kg\cdot K} \right)\cdot \ln \frac{288.15\,K}{373.15\,K}[/tex]
[tex]s_{2} - s_{1} = -1083.112\,\frac{J}{kg\cdot K}[/tex]
The change in entropy is -1083.112 joules per kilogram-Kelvin.
Answer:
The change in entropy = [tex]-1083.534 J/k[/tex]Explanation:
Change in entropy,
[tex]\delta S = mCp * In[\frac{T2}{T1}][/tex]
The initial temperature,
[tex]T1 = 100^oC\\\\T1 = 100+273\\\\T1 = 373k[/tex]
Final value of temperature,
[tex]T2 = 15^oC\\\\T2 = 15+273\\\\T2 = 288k[/tex]
where,
[tex]m = 1kg\\\\Cp = 4190 J/kg.k[/tex]
Substitute into [tex]\delta S[/tex]
[tex]\delta S = mCp * In[\frac{T2}{T1}]\\\\\delta S = 1 * 4190 * In[\frac{288}{373}]\\\\\delta S = 4190 * In[0.7721]\\\\\delta S = 4190 * [-0.2586]\\\\\delta S = -1083.534 J/k[/tex]
The negative sign exists because the change in entropy will be decreasing due to cooling.
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A 10.00 mL sample of a solution containing formic acid (a weak acid) was placed in a 25 mL volumetric flask and diluted to the mark with water. A 10.00 mL sample of the diluted formic acid solution was then titrated with 0.1322 M sodium hydroxide. The titration required 15.80 mL of sodium hydroxide to reach the equivalence point. Calculate the molarity and the percentage (by mass) formic acid in the original solution. The density of the formic acid solution was found to be 1.02 g/mL.
Answer:
Molarity: 0.522M
Percentage by mass: 2.36 (w/w) %
Explanation:
Formic acid, HCOOH reacts with NaOH as follows:
HCOOH + NaOH → NaCOOH + H₂O
To solve this question we must find the moles of NaOH added = Moles formic acid. Taken into account the dilution that was made we can find the moles -And molarity of formic acid and its percentage by mass as follows:
Moles NaOH = Moles HCOOH:
0.01580L * (0.1322mol / L) =0.002089 moles HCOOH
Moles in the original solution:
0.002089 moles HCOOH * (25mL / 10mL) = 0.005222 moles HCOOH
Molarity of the solution:
0.005222 moles HCOOH / 0.01000L =
0.522MMass HCOOH in 1L -Molar mass: 46.03g/mol-
0.522moles * (46.03g / mol) = 24.04g HCOOH
Mass solution:
1L = 1000mL * (1.02g / mL) = 1020g solution
Mass percent:
24.04g HCOOH / 1020g solution * 100
2.36 (w/w) %
In terms of energy, when atoms chemically bond to form a stable compound:_____.
A. Energy is released.
B. Energy can either be released or consumed depending upon the bond formed.
C. Energy is transferred from one atom to another.
D. Energy is consumed.
Answer:
A. Energy is released
Explanation:
Energy is only released when chemical bonds are formed.
What is the percent yield when 1.72 g of H2O2 decomposes and produces 375 mL of O2 gas measured at 42 oC and 1.52 atm
Answer:
87.0%
Explanation:
Step 1: Write the balanced reaction
H₂O₂ ⇒ H₂O + 0.5 O₂
Step 2: Calculate the real yield of oxygen, in grams
We have 375 mL (0.375 L) of O₂ at 42 °C (315 K) and 1.52 atm. First, we will calculate the number of moles using the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 1.52 atm × 0.375 L / (0.0821 atm.L/mol.K) × 315 K = 0.0220 mol
The molar mass of oxygen is 32.00 g/mol.
0.0220 mol × 32.00 g/mol = 0.704 g
Step 3: Calculate the theoretical yield of oxygen, in grams
According to the balanced equation, the mass ratio of H₂O₂ to O₂ is 34.01:16.00.
1.72 g H₂O₂ × 16.00 g O₂/34.01 g H₂O₂ = 0.809 g O₂
Step 4: Calculate the percent yield of oxygen
We will use the following expression.
%yield = real yield / theoretical yield × 100%
%yield = 0.704 g / 0.809 g × 100% = 87.0%
Considering the reaction stoichiometry and the ideal gas law, the percent yield when 1.72 g of H₂O₂ decomposes and produces 375 mL of O₂ gas measured at 42 °C and 1.52 atm is 86.96%.
Theoretical yield of oxygenThe balanced reaction is:
2 H₂O₂ → 2 H₂O + O₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
H₂O₂: 2 moleH₂O: 2 mole O₂: 1 molesThe molar mass, this is the amount of mass a substance contains in one mole, of H₂O₂ is 34 [tex]\frac{g}{mole}[/tex]. Then, the amount of moles of H₂O₂ that decomposes when 1.72 grams of H₂O₂ reacts is calculated as:
[tex]1.72 gramsx\frac{1 mole}{34 grams}= 0.0506 moles[/tex]
Then you can apply the following rule of three: if by stoichiometry 2 moles of H₂O₂ produce 1 moles of O₂, 0.0506 moles of H₂O₂ will produce how many moles of O₂?
[tex]amount of moles of O_{2} =\frac{0.0506 moles of H_{2} O_{2} x1 mole of O_{2} }{2 moles of H_{2} O_{2}}[/tex]
amount of moles of O₂= 0.0253 moles
Real yield of oxygenOn the other side, an ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P× V = n× R× T
In this case, for O₂ gas you know:
P= 1.52 atmV= 375 mL= 0.375 L (being 1000 mL= 1 L)n= ?R= 0.082 [tex]\frac{atmL}{molK}[/tex]T= 42 °C= 315 °K (being 0°C= 273°K)Replacing:
1.52 atm× 0.375 L = n× 0.082 [tex]\frac{atmL}{molK}[/tex]× 315 K
Solving:
[tex]n=\frac{1.52 atmx 0.375 L}{0.082\frac{atmL}{molK}x 315 K }[/tex]
n= 0.022 moles
Percent yield of oxygenThe percent yield is calculated as
[tex]Percent yield= \frac{real yield}{theoretical yield} x100[/tex]
In this case, for oxygen the percent yield is calculated as
[tex]Percent yield of oxygen= \frac{0.022 moles}{0.0253 moles} x100[/tex]
Percent yield of oxygen= 86.96 %
Finally, the percent yield when 1.72 g of H₂O₂ decomposes and produces 375 mL of O₂ gas measured at 42 °C and 1.52 atm is 86.96%.
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the reaction stoichiometry: brainly.com/question/16487206?referrer=searchResults brainly.com/question/14446695?referrer=searchResults brainly.com/question/11564309?referrer=searchResults brainly.com/question/4025026?referrer=searchResults brainly.com/question/18650135?referrer=searchResultsideal gas lawhttps://brainly.com/question/4147359?referrer=searchResultsCalculate the mass percent (m/m) of a solution prepared by dissolving 51.56 g of NaCl in 164.2 g of H2O. Express your answer to four significant figures. View Available Hint(s)
Answer:
"23.896%" is the right answer.
Explanation:
The given values are:
Mass of NaCl,
= 51.56 g
Mass of H₂O,
= 165.6 g
As we know,
⇒ Mass of solution = [tex]Mass \ of \ (NaCl+H_2O)[/tex]
= [tex]51.56+164.2[/tex]
= [tex]215.76 \ g[/tex]
hence,
⇒ [tex]Mass \ percent =\frac{Mass \ of \ NaCl}{Mass \ of \ solution}\times 100[/tex]
[tex]=\frac{51.56}{215.76}\times 100[/tex]
[tex]=23.896 \ percent[/tex]
Water potential is the potential energy for water to move from one area to another. Water
always moves from a high water potential area to a lower water potential area. According
to the water potential formula, which factors affect the water potential?
a) Pressure and the amount of solute
b) Volume and temperature
c) Surface area and depth
d) Speed and concentration
Answer:
A
Explanation:
The water potential depends upon the pressure and amount of solute according to the water potential formula.
The following points can be considered:
The water potential formula defines as the summation of the solute potential, pressure component, gravimetric component, potential due to humidity, potential due to matrix effects, and the reference correction. The water potential does not depend on the volume and temperature of the system. The water potential does not depend on the surface area and depth of the system. The water potential does not depend on the speed and concentration of the system.Therefore, the correct answer is a) pressure and the amount of solute.
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28. If the total pressure of a mixture of four gases (neon, carbon dioxide, oxygen and hydrogen) is 1245 mm
Hg, what is the pressure of neon gas if the pressure of carbon dioxide is 145 mm Hg, the pressure of hydrogen is
499 mm Hg and the pressure of oxygen is 228 mm Hg?
A) 601 mm Hg
B) 746 mm Hg
C) 872 mm Hg
D) 373 mm Hg
Answer:
D) 373 mm Hg.
Explanation:
We can solve this problem by keeping in mind Dalton's law of partial pressures, which states that the total pressure of a mixture of gases is equal to the sum of each gas' partial pressures. In other words, for this case:
Total Pressure = Ne Pressure + CO₂ Pressure + O₂ Pressure + H₂ Pressure1245 mm Hg = Ne Pressure + 145 mm Hg + 228 mm Hg + 499 mm HgNe Pressure = 373 mm HgThe answer is option D) 373 mm Hg.
a compound decomposes by a first-order process. if 17.0% of the compound decomposes in 60.0 minutes, the half-life of the compound is
Answer:
the half-life of the compound is 223 minutes
Explanation:
Given the data in the question;
compound decomposes by a first-order process,
17% of compound decomposes in 60 minutes,
the half-life of the compound = ?
Since its a first order reaction, we use the expression;
k = 1/t ln( Co/Cf )
given that; t = 30 minutes, Cf = 1 - 17% of Co = 1 - 0.17 of Co = 0.83Co
we substitute
k = ( 1 / 60 min ) ln( Co / 0.83Co )
k = ( 1 / 60 min ) ln( 1 / 0.83 )
k = 0.016667 × 0.186329578
k = 0.003105555
so get the half life;
[tex]t_{1/2[/tex] = 0.693 / k
we substitute
[tex]t_{1/2[/tex] = 0.693 / 0.003105555
[tex]t_{1/2[/tex] = 223.14 ≈ 223 minutes
Therefore, the half-life of the compound is 223 minutes
What is the [OH-] of a solution with a pH of 1.4?
Answer:
If a solution has pH=8 , then its pOH is 14−8=6 and the corresponding concentration of hydroxyl OH− ions is 10−6 mol per litre.
Explanation:
WILL GIVE BRAINLIEST!!!
Which of the following conditions remain constant in Boyle's law?
Volume and pressure
Density and temperature
Pressure and number of moles
Temperature and number of moles
Answer: Temperature and number of moles are the conditions which remain constant in Boyle's law.
Explanation:
Boyle's law states that at constant temperature the pressure of a gas is inversely proportional to the volume of gas.
Mathematically, it is represented as follows.
[tex]P \propto \frac{1}{V}[/tex]
As equation for ideal gas is as follows.
PV = nRT
And, at constant temperature the pressure is inversely proportional to volume which also means that number of moles are also constant in Boyle's law.
Thus, we can conclude that temperature and number of moles are the conditions which remain constant in Boyle's law.
Answer:
Temperature and number of moles
Explanation:
Oh no! I dash (lose) my purse
Answer:
Ok
Explanation:
In a thermonuclear device, the pressure of 0.050 liters of gas within the bomb casing reaches 458000 atm. When the bomb casing is destroyed by the explosion, the gas is released into the atmosphere where it reaches a pressure of 1.00 atm. What is the volume of the gas after the explosion
Answer:
22900 L
Explanation:
Assuming the gas behaves ideally, we can solve this problem by using Boyle's law, which states that:
P₁V₁=P₂V₂Where subscript 1 refers to the initial conditions of pressure and volume (within the bomb, namely), while 2 refers to the final conditions.
Meaning that in this case:
P₁ = 458000 atmV₁ = 0.050 LP₂ = 1.00 atmV₂ = ?We input the data:
458000 atm * 0.050 L = 1.00 atm * V₂And solve for V₂:
V₂ = 22900 LThe total number of sodium atoms in 46.0 grams of sodium
is
Select all of the abiotic factors in an ecosystem.
Plants
Sunlight
Soil
Animals
Rocks
Dead deer in the forest
Temperature
Answer:
Sunlight, Soil, Rocks, Temperature and dead deer
Explanation:
You could say the dead tree is now an abiotic factor because biotic factors refer to living things
What is the hydrogen ion concentration of a solution with a pH of 2.0?
Answer:
[H+] = 10^-2
Explanation:
pH = -log[H+]
2 = -log[H+]
[H+] = 10^-2
PLEASE!! HELP!!
A 25.0 L balloon at 20ºC is placed in a hot water bath at 90ºC. After 15 minutes, the volume of the balloon stops expanding. What is the new volume of the balloon?
Answer:
After 15 minutes,the volume of the balloon stops expanding
What happens if more product is added to a system at equalibrium
Answer:
There won't be any equilibrium.
Explanation:
Because when we add a product to a system then the equilibrium will not be the same since the weight will be more on one system which will make it unstable.
As the temperature increases from 0°C to 25°C the amount of NH3 that can be dissolved in 100 grams of water.
A) decreases by 10 grams
B) decreases by 40 grams
C) increases by 10 grams
D) increases by 40 grams
Answer:
decreases by 10 gram
Explanation:
Name and describe the type of bond found in a water molecule.
Answer:
covalent bonds
Explanation:
covalent bonds hold together the hydrogen and oxygen atoms of individual H2O molecules. Covalent bonds occur when two atoms share electrons with each other.
Which is a characteristic of aromatic hydrocarbons?
A. Alternating single and double bonds
B. Bonds between oxygen and carbon atoms
C. Oxygen atoms bonded to hydrogen atoms
D. Two hydrogen atoms bonded together
Answer:
A. Alternating single and double bonds
Explanation:
Hydrocarbons i.e. hydrogen and carbon containing compounds, are grouped into two namely: aliphatic and aromatic hydrocarbons. Aliphatic hydrocarbons contains straight or branched chains of carbon and hydrogen atoms in their structure e.g. alkanes, alkenes etc.
On the other hand, aromatic hydrocarbons are cyclic hydrocarbons containing one or more cyclic rings. The benzene ring is the basis of all aromatic hydrocarbons and one characteristics of benzene is that it possesses an alternating single (-) and double bonds (=) in their structure.
Since benzene is a building constituent of aromatic hydrocarbons, an "alternating single and double bond" is a characteristics of aromatic hydrocarbons.
Heat is added to two identical samples of a monatomic ideal gas. In the first sample, the heat is added while the volume of the gas is kept constant, and the heat causes the temperature to rise by 80 K. In the second sample, an identical amount of heat is added while the pressure (but not the volume) of the gas is kept constant. By how much does the temperature of this sample increase
Answer:
The temperature of the sample increase by 48 Kelvin
Explanation:
The sample is identical.
Hence the heat at constant pressure is equal to the heat at the constant Volume
Q1 = Q2
Q 1 = heat at constant pressure
Q2 = heat at the constant Volume
Substituting the given values, we get -
[tex]\frac{3}{2} nRT_1 = \frac{5}{2} nRT_2\\3 * 80 = 5 * T_2\\T_2 = 48[/tex]
The temperature of the sample increase by 48 Kelvin
21. A piece of metal with a a mass of 15.2 g is heated from 17°C to 42°C. In the process it absorbs 1362 J of
energy as heat. What is the specific heat of the metal?
Answer:
3584.21 J/kg.K
Explanation:
Applying
Q = cm(t₂-t₁)........... equation 1
Where Q = Quantity of heat absorb, c = specific heat capacity of the metal, m = mass of the metal, t₁ = intial temperature, t₂ = Final temperature.
make c the subject of the equation
c = Q/(m(t₂-t₁)........... Equation 2
From the question,
Given: Q = 1362 J, m = 15.2 g = 0.0152 kg, t₁ = 17°C, t₂ = 42°C
Substitute these values into equation 2
c = 1362/0.0152(42-17)
c = 1362/0.38
c = 3584.21 J/kg.K
b. Calculate the empirical formula of a formula unit with the following percent compositions: 59.7%
lithium (Li) and 40.3% nitrogen (N). Complete the table to help with the calculations. (5 points)
Given
Li - 59.7 %
N - 40.3 %
Solution,
First get the molar mass of each Atom,
Li- 6.941
N- 14.00
Second find the moles of both atom,
moles of Li = 59.7/6.941 = 8.60
Moles of N = 40.3/14 = 2.87
Third devide both the moles with smaller mole,
first- 8.6÷2.87 = 2.99 ~ 3
second 2.87÷2.87 = 1
Ratio of Li to N is 3:1
The compound is Li3N.
1. How many moles of hydrogen are needed to completely react with two moles of nitrogen?
_N2 + _H2 -->_NH3
Please hurry it is for a big assignment
N2 + 3H2 --> 2NH3
Answer: 6 moles of hydrogen are needed to react with two moles of nitrogen.
Explanation:
Benzaldehyde and benzyl alcohol can be distinguished by NMR. The proton on the aldehyde group will appear at approximately _____ ppm; the methylene peak on the alcohol is the only peak ______ ppm for either compound.
Answer:
9-10 ppm.
0.2-0.4 ppm.
Explanation:
The proton on the aldehyde group will appear at approximately 9-10 ppm whereas the methylene peak on the alcohol is the only peak 0.2-0.4 ppm for either compound. Aldehydes and aromatics are quite distinctive in the Nuclear magnetic resonance (NMR). Aldehydes show up from 9-10 ppm, usually as a small singlet; aromatic protons show up from 6.5-8.5 ppm. NMR spectroscopy is the use of NMR to study the physical, chemical, and biological properties of matter.
Evaluate each of the statements below. Select those that accurately describe the role of genes and chromosomes in
the process of inheriting a specific trait. Choose ALL that apply.
-0)
A)
Chromosomes are made of DNA.
B)
There are 26 pairs of chromosomes in humans.
C)
Alleles are the different forms of a gene that can exist.
D)
Chromosomes contain genes that control the inheritance of traits.
E)
Genes are made of chromosomes and contain all of the genetic information
for an organism.
Answer:
HEY CAN YOU POST YOUR LAST QUESTION AGAIN? CAUSE I HAVE THE ANSWER
Is nuclear energy good or bad?
Answer:
It is bad
Explanation:
Is nuclear energy good or bad?
Two iron-clad characteristics of matter
are that it has mass and also exhibits
which of the following?
A. It flows from hot to cold.
B. It can do work,
C. It has volume (takes up space).
D. It is a solid.
Answer:
it has volume( takes up space).
Explanation:
The characteristics of matter are that it has mass and also exhibits volume (takes up space).Hence Option (C) is Correct.
What is Matter ?A physical substance in general, that which occupies space and possesses rest mass, especially as distinct from energy.
Matter is important because it makes up everything around us and matter can not be created or destroyed but instead, they just transformed into a different form.
Any characteristic that can be measured, such as an object's density, colour, mass, volume, length, malleability, melting point, hardness, odour, temperature, and more, are considered properties of matter.
Therefore, The characteristics of matter are that it has mass and also exhibits volume (takes up space).Hence Option (C) is Correct.
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I need the answer fast pls it’s scince
Answer:
more dense
Explanation:
cold air particles are moving slower, because they have less energy.
What is the mass in grams of 5.50 moles of Copper, Cu?
Answer:
349.503 g
https://www.convertunits.com/from/moles+Copper/to/grams
here is a link, you can convert moles of copper to grams here
The answer is 5.50 moles of Cu (Copper) has 349.503 grams mass .
What is a mole ?
A mole is defined as 6.02214076 × 10²³ atoms, molecules, ions, or other chemical units.
and the molar mass of a substance is defined as the mass of 1 mole of that substance, expressed in grams per mole.
It is equal to the mass of 6.022 × 10 23 atoms, molecules, or formula units of that substance.
1 mole of Cu has 63.546 grams of Cu
So 5.50 moles will have 5.50 * 63.546 grams
=349.503 grams
Therefore 5.50 moles of Cu (Copper) has 349.503 grams mass .
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