Answer:
1.62 g
Explanation:
Given that:
Concentration of HCN = 0.119 M
Assuming the ka 4.00 × 10⁻¹⁰
The pKa of HCN (hydrocyanic acid) = -log (Ka)
= - log ( 4.00 × 10⁻¹⁰)
= 9.398
pH of buffer = 8.809
Using Henderson Hasselbach equation:
[tex]pH = pKa + log \dfrac{[conjugate\ base ]}{acid}[/tex]
[tex]pH = pKa + log \dfrac{[CN^-]}{[HCN]}[/tex]
[tex]8.809 = 9.398 +log \dfrac{[CN^-]}{[HCN]}[/tex]
[tex]log \dfrac{[CN^-]}{[HCN]}= 8.809 - 9.398[/tex]
[tex]log \dfrac{[CN^-]}{[HCN]}= -0.589[/tex]
[tex]\dfrac{[CN^-]}{[HCN]}= 0.2576[/tex]
[CN^-] = 0.2576[HCN]
[CN^-] = 0.2756 (0.119) L
[CN^-] = 0.033 M
∴
The amount of NaCN (sodium cyanide) is calculated as follows:
[tex]= 1.00 L \times \dfrac{0.033 \ mol \ NacN }{1 \ L } \times \dfrac{49.01 \ g}{1 \ mol \ of \ NacN}[/tex]
= 1.62 g
Lab 2: paper chromatography of organic dyes
Picture of questions below.
Answer:
The three primary colors used when mixing dyes or paints are red, yellow, and blue. Other colors are often a mixture of these three colors. Try running a chromatography test again with non-primary-color markers, like purple, brown, and orange.
Explanation:
Mixtures that are suitable for separation by chromatography include inks, dyes and colouring agents in food. ... As the solvent soaks up the paper, it carries the mixtures with it. Different components of the mixture will move at different rates. This separates the mixture out.
One source of aluminum metal is alumina, Al2O3. a. Determine the percentage composition of Al in alumina. b. How many pounds of aluminum can be extracted from 2.0 tons of alumina.?
Answer:
sorry i cant give the answer but you can gi end check in answer sheet of this becoz i had same question in exam in chemistry so i revised then i checked the answer if you want to check answer go to www.coachscotchemistry.com there you xan find the answer
Convert the following:
1) 367.5 mg = _______ g
2) 367 mL = _______ L
3) 28.59 in =______ cm
4) 8 0z =_______lb
5) 0.671 mm =_____m
When a liquid is heated the average what? Of energy of its particles will increase
A tank at is filled with of sulfur tetrafluoride gas and of sulfur hexafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction of each gas. Round each of your answers to significant digits.
The question is incomplete, the complete question is:
A 7.00 L tank at [tex]21.4^oC[/tex] is filled with 5.43 g of sulfur hexafluoride gas and 14.2 g of sulfur tetrafluoride gas. You can assume both gases behave as ideal gases under these conditions. Calculate the mole fraction and partial pressure of each gas. Round each of your answers to significant digits.
Answer: The mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)
For sulfur hexafluoride:Given mass of sulfur hexafluoride = 5.43 g
Molar mass of sulfur hexafluoride = 146.06 g/mol
Putting values in equation 1, we get:
[tex]\text{Moles of sulfur hexafluoride}=\frac{5.43g}{146.06g/mol}=0.0372mol[/tex]
For sulfur tetrafluoride:Given mass of sulfur tetrafluoride = 14.2 g
Molar mass of sulfur tetrafluoride = 108.07 g/mol
Putting values in equation 1, we get:
[tex]\text{Moles of sulfur tetrafluoride }=\frac{14.2g}{108.07g/mol}=0.1314mol[/tex]
Total moles of gas in the tank = [0.0372+ 0.1314] mol = 0.1686 mol
Mole fraction is defined as the moles of a component present in the total moles of a solution. It is given by the equation:
[tex]\chi_A=\frac{n_A}{n_A+n_B}[/tex] .....(2)
where n is the number of moles
Putting values in equation 2, we get:
[tex]\chi_{SF_6}=\frac{0.0372}{0.1686}=0.221[/tex]
[tex]\chi_{SF_4}=\frac{0.1314}{0.1686}=0.779[/tex]
Hence, the mole fraction of sulfur hexafluoride is 0.221 and that of sulfur tetrafluoride is 0.779
Round 5578 L to three significant figures.
a. 557 L
b. 558 L
c. 5.58 x 10(3) L
d. 5.58 x 10(-3) L
Answer:
b
Explanation:
The figures of a number that are noteworthy in high accuracy or precision are known as significant figures. They are as follows:
Any digit that isn't zeroAs in 20012 or 64.60007, there are zeros between non-zero numbers.Only use leading zeros when a decimal point is present, such as in 5640.0 or 532.330.If the figure is less than 5, remove it and leave the rest of the number unaffected but if more than 5 add, round it up to 1, and add it to the next figure in the line.From the given information:
To (3) sig. fig: 5578 L = 558 L
Match the below mention gas law.
____________ states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.
__________ states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).
____________ states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).
1. Boyle's law
2. Charles's law
3. Avogadro's law
Answer:
Charles's law states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.
Boyle's law states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).
Avogadro's law states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).
Explanation:
Charles's law says that at constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases. This is because "temperature" means movement of the particles. So, the greater the movement of the particles (temperature), the greater the volume of the gas. Then, Charles's law indicates that the volume is directly proportional to the temperature of the gas.
So, Charles's law states that the volume of a gas is directly proportional to the temperature of the gas, while pressure and number Of moles are kept constant (V/T = constant). All temperatures must be in kelvins when used in gas law calculations.
As the volume increases, the gas particles (atoms or molecules) take longer to reach the walls of the container and therefore collide with them fewer times per unit of time. This means that the pressure will be lower because it represents the frequency of collisions of the gas against the walls. In this way pressure and volume are related, determining Boyle's law which says:
"The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure"
So, Boyle's law states that the volume of the gas varies inversely to the pressure on the gas, while temperature and number of moles are kept constant (PV = constant).
Avogadro's Law is a gas law that relates the volume and quantity of gas at constant pressure and temperatures. This law states that the volume of a gas held at constant temperature and pressure is directly proportional to the number of moles of the gas: if the amount of gas increases, the volume will increase, and if the amount of gas decreases, the volume decreases.
Then, Avogadro's law states that the volume of a gas is directly proportional to the number of moles of the gas, while pressure and temperature are kept constant (V/n constant).
Answer:
Boyle's Law: This gas relates pressure and volume at a fixed Temperature.
Charles' Law: This gas law relates the volume of a given mass and its temperature at a fixed pressure.
Avogadro's Law: This gas law relates the volume occupied by an ideal gas and the number of moles present at a fixed temperature and pressure.Avogadro's Law
Ideal Gas Law: This law states that the volume of any gas is directly proportional to the number of moles of the gas and the temperature of the gas and is inversely proportional to the pressure of the gas.
Helllppp asapppp
Which of the following is matter?
O A. Light
O
B. Sound
O C. Atoms
O D. Radio waves
Whether or not the process is observed in nature, which of the following could account for the transformation of phosphorus-28 to silicon-28?
a. beta decay.
b. eletron capture
c. positron emission
d. alpha decay
Answer:
positron emission
Explanation:
Positron emission,involves the decrease in the nuclear positive charge thus the atomic number of the daughter nucleus decreases by one unit compared to that of the parent nucleus while the mass number of the daughter nucleus remains the same as that of the parent nucleus.
Thus, when phosphorus-28 is transformed into to silicon-28, a positron emission has taken place because the mass number of the daughter nucleus remained the same while the atomic number of the daughter nucleus was decreased by one unit.
Hey what is your guyses fear, I am terrified of wasp, especially those huge red ones I call red goobers.
g What happens to the intensity of the solution's color as the concentration of the solute changes? The intensity of the color directly changes in response to the concentration. The intensity of the color inversely changes in response to the concentration. The intensity of the color always increases in response to any concentration change. The intensity of the color always decreases in response to any concentration change. The intensity of the color does not change in response to any concentration change.
Answer:
The intensity of the color directly changes in response to the concentration
Explanation:
One of the major indicators of the concentration of a solution is the colour of the solution.
The colour of the solution changes as the concentration of the solution changes. If the solution becomes more concentrated, the colour of the solution becomes deeper. If the solution becomes more dilute, the colour of the solution becomes lighter.
It then follows that, the intensity of the color of a solution directly changes in response to the concentration of the solution.
Which state of matter is characterized by having an indefinite shape, but a definite volume?
solid
gas
liquid
Answer:
liquid is the right answer k
Answer:
liquid
Explanation:
What is the specific heat value of brass?
Answer:
Nhiệt dung riêng của đồng là
380
J
/
k
g
.
K
Explanation:
According to hydrogen’s chemical properties, it belongs in the same group as:
1. alkali metals
2. alkaline earth metals
3 .halogens
4. both a and c
---
Select the following group of elements that contains elements with similar chemical properties
A.
N, As, Bi
B.
Rb, Sn, In
C.
Li, Mg, Ga
D.
W, Tc, Fe
---
A solution of KMnO4 has an absorbance of 0.539 when measured in the colorimeter. Determine the concentration of the KMnO4 given the following data for a calibration plot.
Concentration of KMNO4 (M) Absorbance
0.0150 0.081
0.0300 0.159
0.0450 0.260
0.0600 0.334
Answer:
Concentration of unknown solution is 0.0416 M
Explanation:
As we know
Absorbance is equal to the product of molar absorptivity of KMnO4 m, path length and concentration
From the given set of graphical data, it is clear that the absorbance vs concentration is a straight line.
From the graph, we can obtain-
Y = 5.73 X – 0.0065
Absorbance = 0.232
0.232 = 5.73 X – 0.0065
X = 0.0416
Concentration of unknown solution is 0.0416 M
What is the pH of a 1.7 × 10⁻⁴ M HClO₄ solution?
What would you use to measure
to measure an amount of solid sodium chloride(NaCI)
crystals to add to a 30 mL solution?
A. Triple Beam Balance that measures to the nearest 0.1 grams.
) B. 10 ml graduated cylinder.
Scale that can weigh up to 250 lbs.
D. Spectrophotometer that measures between 100 and 900 nanometers.
One of the nuclides in spent nuclear fuel is U-235, an alpha emitter with a half-life of 703 million years. How long will it take for an amount of U-235 to reach 23.0% of its initial amount
Answer:
1.49 × 10⁹ years
Explanation:
Step 1: Calculate the rate constant (k) for the nuclear decay of U-235
The decay follows first-order kinetics with a half-life (t1/2) of 703 × 10⁶ years. We can calculate "k" using the following expression.
k = ln2/ t1/2 = ln2 / 703 × 10⁶ y = 9.86 × 10⁻¹⁰ y⁻¹
Step 2: Calculate the time elapsed (t) so that the final amount ([U]) is 23.0% of the initial amount ([U]₀)
For first order kinetics, we will use the following expression.
ln ([U]/[U]₀) = -k × t
ln (0.230[U]₀/[U]₀) = -9.86 × 10⁻¹⁰ y⁻¹ × t
ln 0.230 = -9.86 × 10⁻¹⁰ y⁻¹ × t
t = 1.49 × 10⁹ y
You HAVE 1L of 2.0 mol/L HCI. You want to dilute the solution to a concentration of 0.1 mol/L. What volume of the new solution (V2)?
0.05 L
O 20L
0.2 L
M₁ = 2.0 mol/L
V₁ = 1 L
M₂ = 0.1 mol/L
Required:V₂
Solution:M₁V₁ = M₂V₂
V₂ = M₁V₁ / M₂
V₂ = (2.0 mol/L)(1 L) / (0.1 L)
V₂ = 20 L
Therefore, the volume of the new solution will be 20 L.
#ILoveChemistry
#ILoveYouShaina
M₁V₁ = M₂V₂
V₂ = M₁V₁ / M₂
V₂ = (2.0 mol/L)(1 L) / (0.1 L)
V₂ = 20 L
THE BEST ANSWER IS
O 20L
what is the maximum number of grams of sodium chloride that you could dissolve in 500 grams of water at 20 C
Answer:
178.5g of NaCl is the maximum amount that can be dissolved
Explanation:
Solubility is defined as the maximum amount of solute that can be dissolved in aAt 20°C, the solubility of NaCl is 35.7g per 100g of water at 20°C. That means the maximum amount that can be dissolved of NaCl is:
500g water * (35.7g NaCl / 100g water) =
178.5g of NaCl is the maximum amount that can be dissolvedA flexible vessel contains 65.8 L of gas at a pressure of 2.07 atm. Under the conditions of constant temperature and constant number of moles of gas, what is the pressure of the gas (in atm) when the volume of the vessel increased by a factor of 16.00
Answer: Pressure of the gas is 0.129375 atm when the volume of the vessel increased by a factor of 16.00.
Explanation:
The formula for ideal gas equation is as follows.
[tex]PV = Nk_{b}T[/tex]
where,
[tex]k_{b}[/tex] = Boltzmann constant
N = number of moles
That can also be written as:
[tex]\frac{PV}{T} = constant[/tex]
As pressure and volume are inversely proportional to each other. So, if one of the state variable is increased then the other one will decrease or vice-versa.
So, if volume of the vessel increased by a factor of 16.00 then it means pressure is decreased by a factor of 16.00
Therefore, final volume is as follows.
[tex]65.8 L \times 16.00\\= 1052.8 L[/tex]
Now, final pressure is as follows.
[tex]\frac{2.07}{16.00}\\= 0.129375 atm[/tex]
Initially the product of pressure and volume is as follows.
[tex]PV = 2.07 \times 65.8\\= 136.206[/tex]
Hence, if volume of the vessel increased by a factor of 16.00 and pressure is decreased by a factor of 16.00 then its product is as follows.
[tex]PV = 0.129375 \times 1052.8\\= 136.206[/tex]
Here, product of pressure and volume remains the same.
Thus, we can conclude that pressure of the gas is 0.129375 atm when the volume of the vessel increased by a factor of 16.00.
HELP ME PLZ AND THANKS I WILL MARK YOU AS BRAINLIEST!!!
Answer:
i think formula is PV=K?
Explanation:
Write a balanced equation for the combination reaction described, using the smallest possible integer coefficients. When methane (CH4) combines with carbon tetrachloride , dichloromethane (CH2Cl2) is formed.
Answer:
C H₄ + C Cl₄ = 2 (C H₂ Cl₂)
To prepare a sample in a capillary tube for a melting point determination, gently tap the tube into the sample with the ___________ end of the tube down. Continue tapping until the sample. _____________ Then, with the __________ end of the tube down, tap the sample down slowly or __________ to move the sample down faster. Finally, make sure that you can see ___________ in the magnifier when placed in the melting point apparatus before turning on the heat.
Answer: Hello I was able to find the missing options related to your question online but I couldn't attach them hence I just used them to provide the relevant solution
answer:
Open Is a couple of millimeters highclosed Drop tube into a longer tube sample clearlyExplanation:
OPEN end of the tube down. Continue tapping until the sample. Is a couple of mm high Then, with the Closed end of the tube down, tap the sample down slowly or drop tube into a longer/larger tube to move the sample down faster. Finally, make sure that you can see sample clearly in the magnifier when placed in the melting point apparatus before turning on the heat.
What is the volume of 0.410 moles of co2 at STP
Answer: 9.18 Litres
Standard Temperature and Pressure (STP). Think of this as the perfect environment where the Temp. is 0°C or 273 Kelvin and Pressure is always 1 atm. This is only true in STP.
This question uses the Ideal Gas Equation:
PV=nRT
P= 1 atm
V = ??
T = 273 K (always convert to Kelvin unless told otherwise)
n = 0.410 mol
R = 0.0821 L.atm/mol.K
What R constant to use depends on the units of the other values. (look at the attachments) The units cancel out and only Litres is left. You simply multiply the values.
Answer:
9.18 liters .............
heya
what is a colloidal with liquid as both dispersed phase and dispersion medium called?
Answer:
A colloidal system in which liquid is a dispersed phase and solid is dispersion medium is known as Gel.
Explanation:
Name the following ketone:
A. 2,3,5,6-tetraethyl-4-octanal
B. 2,3,5,6-tetramethyl-4-octanone
C. 2,3,5,6-tetramethyl-4-octaketone
Answer:
it is b step by step
Explanation:
The naming of this compound is 2,3,5,6 tetramethyl-4-octane.
Hence, option (B) is correct answer.
What is Ketone ?
A ketone is functional group which contains the carbonyl group that is -C = O. The structure for ketone is R¹ - C = O - R² where R¹ and R² are alkyl group or aryl group.
How to naming a compound ?First we have to find the longest continuous carbon chain. Then identify and start naming the functional groups attached to the chain. Starting the numbering of a compound which is starting at the end nearest a group.Here we can see that the longest carbon chain is Octane. And the functional group is here ketone so suffix is -one. Now starting the number from the left hand side. We can see that on 2, 3,5,6 positions methyl group is attached in this chain. On 4th position ketone group is attached.
So the naming of the ketone is 2,3,5,6 tetramethyl-4-octane.
Thus, from above conclusion we can say that the naming of this compound is 2,3,5,6 tetramethyl-4-octane.
Hence, option (B) is correct answer.
Learn more about the Ketone function group here: https://brainly.com/question/27425066
#SPJ2
Hydrogen and chlorine gases react to form HCl. You and a friend are on opposite sides of a long hallway, you with H2 and your friend with Cl2. You both want to form HCl in the middle of the room. Which of the following is true?
a) You should release the H2 first.
b) Your friend should release the Cl2 first.
c) You both should release the gases at the same time.
d) You need to know the length of the room to answer this question.
e) You need to know the temperature to answer this question.
Answer: It is true that Your friend should release the [tex]Cl_{2}[/tex] first.
Explanation:
The velocity of particles of a gas is inversely proportional to the mass of gas. This means that more is the mass of gas less will be its velocity.
Or, more will be the mass of gas more slowly it will move from one place to another.
The molar mass of chlorine gas is more than the molar mass of hydrogen gas. Therefore, chlorine gas will move slowly.
So, your friend should release the [tex]Cl_{2}[/tex] gas first and then according to the length of room you should release the [tex]H_{2}[/tex] gas.
Thus, we can conclude that it is true that Your friend should release the [tex]Cl_{2}[/tex] first.
write the formula
sodium ion
Answer:
NA+
Explanation:
NA+
hope help
it's NA+
Write the formula of sodium ion.
[tex]\implies {\blue {\boxed {\boxed {\purple {\sf { {Na}^{ + } }}}}}}[/tex]
[tex]\bold{ \green{ \star{ \orange{Mystique35}}}}⋆[/tex]
Identify the indicated protons in the following molecules as unrelated, homotopic, enantiotopic, or diastereotopic. a) Methyls a & b: _________ b) Ha & Hc: _________
Answer:
Identify the indicated protons in the following molecules as unrelated, homotopic, enantiotopic, or diastereotopic. a) Methyls a & b: _________ b) Ha & Hc: ________
Explanation:
Homotopic hydrogens:
Consider two hydrogens in the given molecule and replace one by one with a different atom say for example deuterium, then if the two molecules formed by replacing hydrogens are the same then the two hydrogens are called homotopic hydrogens.
After replacing the two hydrogens with a different atom then, enantiomers are formed then, the two hydrogens are called enantiotopic hydrogens.
After replacing the two hydrogens with a different atom then, diastereomers are formed then, the two hydrogens are called diastereotopic hydrogens.
In the methyl group, select two hydrogens and replace one hydrogen atom with a D-atom name the compound.
Again replace another hydrogen atom with D-atom.
Name it.
If both are the same then, the hydrogens are homotopic and they are shown below:
Hence, they are homotopic protons.