Answer: The freezing point (in °C) of a 0.743 m aqueous solution of KCI is [tex]2.763^{o}C[/tex].
Explanation:
Given: Molality = 0.743 m
[tex]K_{f}[/tex] for water = [tex]1.86^{o}C/m[/tex]
The equation for dissociation of KCl when dissolved in water is as follows.
[tex]KCl \rightarrow K^{+} + Cl^{-}[/tex]
As it is giving 2 ions. Therefore, Van't Hoff factor for it is equal to 2.
Formula used to calculate the freezing point is as follows.
[tex]\Delta T_{f} = i \times K_{f} \times m[/tex]
where,
i = Van't Hoff factor
[tex]K_{f}[/tex] = molal depression constant
m = molality
Substitute the values into above formula as follows.
[tex]\Delta T_{f} = i \times K_{f} \times m\\= 2 \times 1.86^{o}C/m \times 0.743 m\\= 2.763^{o}C[/tex]
Thus, we can conclude that the freezing point (in °C) of a 0.743 m aqueous solution of KCI is [tex]2.763^{o}C[/tex].
8. Calculate (H^+), (OH^-), pOH and the pH for a 0.00024 M solution of calcium hydroxide. Must show work!
Answer:
1. [H⁺] = 2.0×10¯¹¹ M
2. [OH¯] = 4.8×10¯⁴ M
3. pOH = 3.3
4. pH = 10.7
Explanation:
From the question given above, the following data were obtained obtained:
Molarity of Ca(OH)₂ = 0.00024 M
We'll begin by calculating the concentration of the hydroxide ion [OH¯]. This can be obtained as follow:
Ca(OH)₂ (aq) —> Ca²⁺ + 2OH¯
From the balanced equation above,
1 mole of Ca(OH)₂ produced 2 moles of OH¯.
Therefore, 0.00024 M Ca(OH)₂ will produce = 2 × 0.00024 = 4.8×10¯⁴ M OH¯
Thus, the concentration of the hydroxide ion [OH¯] is 4.8×10¯⁴ M
Next, we shall determine the pOH of the solution. This can be obtained as follow:
Concentration of the hydroxide ion [OH¯] = 4.8×10¯⁴ M
pOH =?
pOH = –Log [OH¯]
pOH = –Log 4.8×10¯⁴
pOH = 3.3
Next, we shall determine the pH of the solution. This can be obtained as follow:
pOH = 3.3
pH =?
pH + pOH = 14
pH + 3.3 = 14
Collect like terms
pH = 14 – 3.3
pH = 10.7
Finally, we shall determine the concentration of hydrogen ion [H⁺]. This can be obtained as follow:
pH = 10.7
Concentration of hydrogen ion [H⁺] =?
pH = –Log [H⁺]
10.7 = –Log [H⁺]
Divide both side by –1
–10.7 = Log [H⁺]
Take the antilog of –10.7
[H⁺] = Antilog (–10.7)
[H⁺] = 2.0×10¯¹¹ M
SUMMARY:
1. [H⁺] = 2.0×10¯¹¹ M
2. [OH¯] = 4.8×10¯⁴ M
3. pOH = 3.3
4. pH = 10.7
other two substances present in breathed out air
Answer:
Gases we Breathe Out
It is the same air that we inhale. ... The amount of inhaled air contains 21% of oxygen and 0.04% of carbon dioxide, while the air we breathe out contains 16.4% of oxygen and 4.4% of carbon dioxide.
Answer:
Inhaled air is by volume 78% nitrogen, 20.95% oxygen and small amounts of other gases including argon, carbon dioxide, neon, helium, and hydrogen. The gas exhaled is 4% to 5% by volume of carbon dioxide, about a 100 fold increase over the inhaled amount.
what is the major organic product obtained from the following sequence of reactions 1. naoch2ch3 ch3ch2oh 2. ph br 1. naoch2ch3 ch3ch2oh 2. br 1. lialh4 et2o 2. h3o
A gas has a volume of 6.00 liters at a temperature of 300 K and a pressure of 1.00 atm what is the volume of the gas in liters at a temperature of 600 K and a pressure of 3.00 atm
Answer:
V₂ = 4.00 L
Explanation:
Given that:
Volume (v1) = 6.00 L
Temperature (T1) = 300 K
Pressure (P1) = 1.00 atm
VOlume (V2) = unknown???
Temperature (T2) = 600 K
Pressure (P2) = 3.00 atm
Using combined gas law equation:
[tex]\dfrac{P_1V_1}{T_1}= \dfrac{P_2V_2}{T_2}[/tex]
[tex]\dfrac{1 \times 6}{300} = \dfrac{3 \times V_2}{600}[/tex]
[tex]\dfrac{1}{50} = \dfrac{1 \times V_2}{200}[/tex]
200 = 50V₂
V₂ = 200/50
V₂ = 4.00 L
Pls help I’ll brainlest and add extra points
Answer:
a top predator, fighting
4.3 x 10^2 - 7.0 x 10^2 in scientific notation
How many total number of hydrogen atoms present in CH4?
Answer:
4 Hydrogen atoms
What is the Molar mass of zinc
65.38 u (or g)
I just searched it up
Ar
Si
K
Al
An atom of which element in the table above has the highest
number of neutrons?
Answer: ar
Explanation:
a law that protects citizens against xenophobia
The Promotion of Equality and Prevention of Unfair Discrimination Act, (PEPUDA or Equality Act, 4 of 2000
Explanation:
Xenophobia is known as the dislike for the people from other countries.
the law, prevents and prohibits discrimination and harrasment
What determines how atoms will bond?
Answer:
Explanation:
The number of electrons in the outermost shell of a particular atom determines its reactivity, or tendency to form chemical bonds with other atoms.
Which of the following is an example of an environmental impact of agriculture?
high use of mineral resources
high use of water
high use of gold, copper, and silver
high use of rock supplies
Answer:
high use of mineral resources
Explanation:
brainliest pls
Calculate the volume of 0.250 M H2SO4 that contains 0.00255 mol H2SO4.
Answer:
0.0102 L or 10.2 mL
Explanation:
From the question given above, the following data were obtained:
Molarity = 0.250 M
Mole = 0.00255 mole
Volume =?
Molarity is simply defined as the mole of solute per unit litre of the solution. Mathematically, it is expressed as:
Molarity = mole / Volume
With the above formula, we can obtain the volume as follow:
Molarity = 0.250 M
Mole = 0.00255 mole
Volume =?
Molarity = mole / Volume
0.250 = 0.00255 / volume
Cross multiply
0.250 × volume = 0.00255
Divide both side by 0.250
Volume = 0.00255 / 0.250
Volume = 0.0102 L
Covert 0.0102 L to mL.
1 L = 1000 mL
Therefore,
0.0102 L = 0.0102 L × 1000 / 1 L
0.0102 L = 10.2 mL
Thus, the volume is 0.0102 L or 10.2 mL
I have a chemistry question: What would be the % composition of sugar in a drink mix solution if 35.0 g of the mix was dissolved in 70.0 g of water. (Assuming that the drink mix is all sugar)
Answer:
50%
Explanation:
35.0g/70.0g×100%
=50%
does anyone know if this is positive,negative or neutral?
Answer:
HERE
Explanation:
Question:
Does anyone know if this is positive,negative or neutral?
Answer:
Netarual
Explanation:
I but the Images down below
A sample of air was collected on a day when the total atmosphere pressure was
592 mmHg. The sample contained only oxygen and nitrogen gas. If the oxygen in the sample had a pressure of 261 mmHg, how much pressure did the nitrogen
have? NOTE: You must show your calculation on the attached scratch paper,
including which of the Gas Law formulas you used. *
A. 853 mm Hg
B. 0.206 mm Hg
C. 4.76 mm Hg
D. 331 mm Hg
(Please show your work)
Answer:
1. The gas law used: Dalton's law of partial pressure.
2. Pressure of nitrogen = 331 mmHg
Explanation:
From the question given above, the following data were obtained:
Total pressure (Pₜ) = 592 mmHg
Pressure of Oxygen (Pₒ) = 261 mmHg
Pressure of nitrogen (Pₙ) =?
The pressure of nitrogen in the sample can be obtained by using the Dalton's law of partial pressure. This is illustrated below:
Pₜ = Pₒ + Pₙ
592 = 261 + Pₙ
Collect like terms
592 – 261 = Pₙ
331 = Pₙ
Pₙ = 331 mmHg
Therefore, the pressure of nitrogen in the sample is 331 mmHg
PLEASEEE HELP!!!! ILL MARK BRAINLESS FIRST PERSON!!!!!
Answer:
A. it should have a cell wall to give it structure
please need help..
no attachments thankyou
1. A sample of a chemical compound has 2.96g carbon, 0.414g hydrogen, 0.675g oxygen and 2.96 sulphur.
calculate it's empirical formula.
2.if it's mass was 972g, determine its molecular formula.
Answer:
1. The empirical formula => C₆H₁₀OS₂
2. Molecular formula => C₃₆H₆₀O₆S₁₂
Explanation:
1. Determination of the empirical formula.
Carbon (C) = 2.96 g
Hydrogen (H) = 0.414 g
Oxygen (O) = 0.675 g
Sulphur (S) = 2.96 g
Divide by their molar mass
C = 2.96 / 12 = 0.247
H = 0.414 / 1 = 0.414
O = 0.675 / 16 = 0.042
S = 2.96 / 32 = 0.0925
Divide by the smallest
C = 0.247 / 0.042 = 6
H = 0.414 / 0.042 = 10
O = 0.042 / 0.042 = 1
S = 0.0925 /0.042 = 2
Therefore, the empirical formula is
C₆H₁₀OS₂
2. Determination of the molecular formula.
Molar mass of compound = 972 g/mol
Empirical formula => C₆H₁₀OS₂
Molecular formula =>?
Molecular formula = [C₆H₁₀OS₂]ₙ
Molecular formula = molar mass of compound
Thus,
[C₆H₁₀OS₂]ₙ = 972
[(12×6) + (10×1) + 16 + (32×2)]n = 972
[72 + 10 + 16 + 64]n = 32
162n = 972
Divide both side by 162
n = 972 / 162
n = 6
Molecular formula = [C₆H₁₀OS₂]ₙ
Molecular formula = [C₆H₁₀OS₂]₆
Molecular formula = C₃₆H₆₀O₆S₁₂
Part F
Using what you have learned in the above questions, calculate the minimum amount of water (in liters) that would be required to completely
dissolve 5.Og AgBr.
Using this same calculation, calculate the minimum amount of water (In liters) that would be required to completely dissolve 26 silver lons.
Answer: did you ever find the answer? I need part E, F, and G if you found them please!!!!! I’m begging, my school year ends in 30 minutes and I gotta get this submitted!!!!!!
Explanation:
In this experiment, you will need to prepare 250.0 mL of 0.100 M KCl(aq) solution. Determine the mass in grams of potassium chloride required to prepare this solution. Type your numerical answer (no units) in the box below. Even though the number of significant figures is limited to three by the inputs, please report your answer to four significant figures.
Answer: The mass in grams of potassium chloride required to prepare this solution is 1.862 grams
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
[tex]Molarity=\frac{n\times 1000}{V_s}[/tex]
where,
n = moles of solute
[tex]V_s[/tex] = volume of solution in ml
moles of [tex]KCl[/tex] = [tex]\frac{\text {given mass}}{\text {Molar mass}}=\frac{xg}{74.5g/mol}[/tex]
Now put all the given values in the formula of molality, we get
[tex]0.100=\frac{x\times 1000}{74.5g/mol\times 250.0ml}[/tex]
[tex]x=1.862g[/tex]
Therefore, the mass in grams of potassium chloride required to prepare this solution is 1.862 grams
Answer correctly for brainliest
only answer the question with the 4 choices in the middle
The force that contributed to the formation of planets, determines the motion of bodies in the solar system, and pulls objects to the center of Earth is called
.
The principle that states that an object at rest will stay at rest and that an object in motion will stay in motion is the law of
Answer:
Gravity and Inertia
Explanation:
Just did it on edg 2021 :)
Can someone please help me with this question.
Answer:
A-Sphalerite + Dioxygen+Zinc Oxide+Sulfur Trioxide
B-Sodium+Magnesium+Sodium iodide
Explanation:
Heyyy love good luck i may be wrong on letter B so if it is thats my bad but A should be correct :)
Which molecule is shown below?
H
H-C-H
H
Η Η Η Η
H-C-C-C-C-C-C-H
1 | | |
H H H H H H
O A. 2-ethylhexane
B. 2-methylhexane
C. 3-ethylhexane
D. 3-methylhexane
Answer:
b. 2-methylhexane
Explanation:
ap3x approved
The molecule shown below is - 2-methylhexane and the correct option is option B.
What is IUPAC Nomenclature?
The IUPAC system of nomenclature is a set of logical rules framed which are mainly aimed at giving an unambiguous name to an organic compound.
IUPAC stands for International Union of Pure and Applied Chemistry
A prefix to the name comes before the molecule. The prefix of the molecule's name is based on the number of carbon atoms.
For example, a chain of six carbon atoms would be named using the prefix hex-.
The suffix to the name is an ending that is applied that describes the types of chemical bonds in the molecule.
The molecule has 6 carbon atoms and a methyl group at the second position.
Therefore, The molecule is 2-methylhexane and the correct option is option B.
Learn more about IUPAC Nomenclature, here:
https://brainly.com/question/30086566
#SPJ7
How/what do I answer this?--> "heat of the chemical reactions"
like this is the question :/
Answer:
The heat of reaction is the energy that is released or absorbed when chemicals are transformed in a chemical reaction. It describes the change of the energy content when reactants are converted into products.
Explanation:
Yeah, that would confuse me a bit but then you read it and then you will get that answer above! Have a great rest of your day!
While recording the crime scene, the photographer snapped a picture of his partner posing beside the famous victim's body. After printing the photo for his partner, he should just delete the image so nobody gets in trouble. (T/F)
While recording the crime scene, the photographer snapped a picture of his partner posing beside the famous victim's body. After printing the photo for his partner, he should just delete the image so nobody gets in trouble is false.
What is photographer?Photographer is defined as a specialist who concentrates on the craft of shooting pictures with a digital or film camera. We can now describe the present, visualize the future, and visualize the history thanks to photography. The predecessor to the contemporary digital camera was the camera obscura. In the past, paintings were the most popular medium for capturing important historical events.
An approach known as "painting with light" is frequently used by seasoned photographers to expose image details in dim or near-dark lighting. By holding the shutter open for a few seconds or minutes while moving around the scene, the photographer can add light from sources like a flashlight or a flash from a separate camera.
The photographer's partner was photographed posing next to the body of the well-known victim as he documented the murder scene. It is erroneous to say that after printing the photo for his spouse, he should immediately erase it.
To learn more about photographer, refer to the link below:
https://brainly.com/question/25379778
#SPJ2
what is the largest recognized landmasses?
Answer:
The continents are, from largest to smallest: Asia, Africa, North America, South America, Antarctica, Europe, and Australia.
Explanation:
There ya go Hope this helped
When ammonium nitrate dissolves in water, the solution becomes cold.
NH4NO3(s) <-> NH4+(aq) + NO3-(aq)
The reaction is thermodynamically favorable. The signs of ΔG and ΔS for the reaction are which of the following?
A.
B.
C.
D.
B.
Delta G is negative and Delta S is positive.
As the temperature in a sample of gas molecules decreases, which
of the other properties of the gas molecules could be caused to
increase or decrease? *
(Please help me)
Answer:
See Explanation
Explanation:
The kinetic energy of gas molecules is related to the temperature of the gas because temperature is a measure of the average kinetic energy of the molecules of a gas hence the lower the temperature of the gas the lower the average kinetic energy of the molecules of the gas.
The volume of a given mass of gas is directly proportional its absolute temperature(Charles's law). Hence, as the temperature of the gas gas decreases, the gas volume also decreases.
The number of gas molecules is totally independent of the temperature of the gas hence it stays the same.
As the temperature decreases, the number of collision of gas particles decreases as the kinetic energy of the gas particles decreases.
The pressure of a given mass of gas is related to the movement of gas particles. Hence, the lower the temperature the lower the pressure of the gas. Pressure and temperature are directly related hence pressure decreases as temperature decreases.
True or false: If a nuclear chain reaction is uncontrolled, it produces a lot of energy all at once. This is
what happens in an atomic bomb.
Answer: False, I think...
Explanation:
Answer:
True
Explanation:
It is uncontrolled