Answer:
pH = 10.9
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to say that the undergoing reaction between this buffer and OH⁻ promotes the formation of more CO₃²⁻ because it acts as the base, we can do the following:
[tex]n_{CO_3^{2-}}=0.34mol/L*0.250L+0.0585mol=0.1435mol\\\\n_{HCO_3^{-}}=0.34mol/L*0.250L-0.0585mol=0.0265mol[/tex]
The resulting concentrations are:
[tex][CO_3^{2-}]=\frac{0.1435mol}{0.25L}=0.574M \\[/tex]
[tex][HCO_3^{-}]=\frac{0.0265mol}{0.25L}=0.106M[/tex]
Thus, since the pKa of this buffer system is 10.2, the change in the pH would be:
[tex]pH=10.2+log(\frac{0.574M}{0.106M} )\\\\pH=10.9[/tex]
Which makes sense since basic OH⁻ ions were added.
Regards!
la. A man was traveling by sie is allowed a maximum of 20kg luggage. The man
weighing 3.5kg, 15kg.2kg and 15kg
Find the excess weight of his luggage.
Express the excess weight as a percentage of the maximum weight allowed
Answer: The excess weight of the luggage is 15.5 kg and its percentage is 77.5%
Explanation:
Given values:
Maximum amount of luggage allowed = 20 kg
Amount of luggage man is carrying = [3.5 + 15 + 2 + 15] kg = 35.5 kg
Excessive weight of the luggage carried = Amount of luggage carrying - Maximum amount of luggage allowed
Excessive weight of the luggage carried = [35.5 - 20] = 15.5 kg
To calculate the percentage of excess weight, we use the equation:
[tex]\% \text{excess weight}=\frac{\text{Excess weight carried}}{\text{Maximum allowed}}\times 100[/tex]
Putting values in above equation, we get:
[tex]\% \text{excess weight}=\frac{15.5kg}{20kg}\times 100\\\\\% \text{excess weight}=77.5%[/tex]
Hence, the excess weight of the luggage is 15.5 kg and its percentage is 77.5%
Determine the number of moles of C in each sample
2.0 mol CH4, 0.175 mol C2H6,
4.21 mol C4H10, 24.5 mol C8 H18
Explanation:
In [tex]CH_4[/tex]:Given moles = 2.0 moles
1 mole of methane contains 1 mole of carbon and 4 moles of hydrogen
Moles of carbon in [tex]CH_4=(2.0\times 1)=2.0 moles[/tex]
In [tex]C_2H_6[/tex]:Given moles = 0.175 moles
1 mole of ethane contains 2 moles of carbon and 6 moles of hydrogen
Moles of carbon in [tex]C_2H_6=(0.175\times 2)=0.35 moles[/tex]
In [tex]C_4H_{10}[/tex]:Given moles = 4.21 moles
1 mole of butane contains 4 moles of carbon and 10 moles of hydrogen
Moles of carbon in [tex]C_4H_{10}=(4.21\times 4)=16.84 moles[/tex]
In [tex]C_8H_{18}[/tex]:Given moles = 24.5 moles
1 mole of octane contains 8 moles of carbon and 18 moles of hydrogen
Moles of carbon in [tex]C_8H_{18}=(24.5\times 8)=196 moles[/tex]
Calculate the number of representative particles of 0.0391 mol Neon gas.
i need help ASAP !
Answer:
2.35 × 10²² particles
Explanation:
To get the number of particles in a substance, we multiply the number of moles (n) of that substance by Avogadro's number (nA).
That is, we say;
number of atoms = n × 6.02 × 10²³
In this question, Neon gas is said to have 0.0391 moles. The number of atoms in that field.
number of particles = 0.0391 × 6.02 × 10²³
number of particles = 0.235 × 10²³
number of particles = 2.35 × 10²² particles
Air bags are activated when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. This causes sodium azide (NaN3) to decompose explosively according to the following reaction. 2 NaN3(s) --> 2 Na(s) 3 N2(g) What mass in grams of NaN3(s) must be reacted in order to inflate an air bag to 79.5 L at STP
Answer:
154 g
Explanation:
Step 1: Write the balanced decomposition equation
2 NaN₃(s) ⇒ 2 Na(s) + 3 N₂(g)
Step 2: Calculate the moles corresponding to 79.5 L of N₂ at STP
At STP, 1 mole of N₂ occupies 22.4 L.
79.5 L × 1 mol/22.4 L = 3.55 mol
Step 3: Calculate the number of moles of NaN₃ needed to form 3.55 moles of N₂
The molar ratio of NaN₃ to N₂ is 2:3. The moles of NaN₃ needed are 2/3 × 3.55 mol = 2.37 mol.
Step 4: Calculate the mass corresponding to 2.37 moles of NaN₃
The molar mass of NaN₃ is 65.01 g/mol.
2.37 mol × 65.01 g/mol = 154 g
1a. A researcher accidentally spilled some sand into his beaker containing crystalline compound X. Knowing what he did about melting points, he was not worried about obtaining the melting point of compound X with a few grains of sand present. Why
Answer:
See explanation
Explanation:
Many organic compounds have low melting points. This is due to the fact that many of these compounds are non polar.
However, compound X is slightly polar but still has a melting point which is far less than that of sand composed of a high melting point inorganic material.
Since sand has a much higher melting point compared to compound X, the researcher need not be worried that sand was spilled into his beaker.
identify the organ system pictured below and state two functions of this system in the body
Answer:
skeletal system
Explanation:
to create and fliter blood and provide frame-work to the human body and support
Given the equation:
H2O (l)
KNO3(s) ————> KNO3(aq)
As H20(l) is added to KNO3(s) to form KNO3(aq), the entropy of the system…
1. decreases
2. increases
3. remains the same
Answer:
2. increases
Explanation:
...............
Answer:
1
Explanation:
Entropy is decrease when product is formed . because of there is stability in the product side.
1. Determine the volume of SO2 (at STP) formed from the reaction of 96.7 mol FeS2 and 55.0 L of O2 at 358 K and 1.20 atm.
4 FeS2(s) + 11O2(g) 2Fe2O3(s) + 8SO2(g)
Answer:
40.0L of SO2 are produced
Explanation:
To solve this question we need to find the moles of O2 using PV = nRT in order to find the moles. Thus, we can find the limiting reactant and the moles (And volume) of SO2 produced as follows:
Moles O2:
n = PV/RT
n = 1.20atm*55.0L / 0.082atmL/molK*358K
n = 2.25 moles of O2.
Clearly, limiting reactant is O2.
The moles of SO2 produced are:
2.25 moles of O2 * (8mol SO2 / 11mol O2) = 1.6351 moles SO2
Volume SO2:
V = nRT/P
V = 1.6351 moles SO2*0.082atmL/molK*358K / 1.20atm
V = 40.0L of SO2 are produced
A diver exhales a bubble with volume of 250 mL at pressure of 2.4 atm and temperature of 15 C. How many gas particulate in this bubble?
Answer:
1.5x10²² particulates
Explanation:
Assuming ideal behaviour, we can solve this problem by using the PV=nRT formula, where:
P = 2.4 atmV = 250 mL ⇒ 250 / 1000 = 0.250 Ln = ?R = 0.082 atm·L·mol⁻¹·K⁻¹T = 15 °C ⇒ 15 + 273 = 288 KWe input the given data:
2.4 atm * 0.250 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 288 KAnd solve for n:
n = 0.025 molFinally we calculate how many particulates are there in 0.025 moles, using Avogadro's number:
0.025 mol * 6.023x10²³ particulates/mol = 1.5x10²² particulatesA 1 liter solution contains 0.402 M hypochlorous acid and 0.302 M potassium hypochlorite. Addition of 0.332 moles of hydrochloric acid will:
Answer:
Lower the pH by several units.
Exceed the buffer capacity.
Explanation:
The options are:
*Raise the pH slightly
*Lower the pH slightly
*Raise the pH by several units
*Lower the pH by several units
*Not change the pH
*Exceed the buffer capacity
The hydrochloric acid reacts with potassium hypochlorite to produce hypochlorous acid. The amount of HCl added is the HClO produced and the KClO consumed. As the moles of HCl > moles KClO, all the KClO is consumed exceeding the buffer capacity and lowering the pH by several units.
What is the role of a decomposer in a food chain?
A. to move food from producers to consumers
B. to move food from consumers to other consumers
C. to make food for the ecosystem
D. to return matter to the environment
Answer:D
Explanation:
Decomposers decompose food and return it to the environment through the soil
Laser fusion Group of answer choices uses chemical reactions to produce energy uses nuclear reactions to produce energy implodes a fuel pellet. causes most of the fuel pellet to produce energy. rotates a fuel pellet.
Answer:
Uses nuclear reactions to produce energy
Implodes a fuel pellet
Explanation:
Laser fusion is a method of initiating nuclear fusion reactions through heating, and compressing fuel pellets containing deuterium and tritium using high energy density laser beams. Lase fusion is also known as inertial confinement fusion and the energy produced by the process is known as Laser Inertial Fusion Energy, LIFE.
During the process of laser fusion, small pellets of deuterium-tritium (DT) isotopes mixture are fed into a blast chamber where they are compressed to high densities using a number of amplified laser beams in the chamber.
The high energy density of the beams as well as the heat produced due to compression, induces the thermonuclear explosion ignition resulting in the production of high energetic products such as charged particles, x-rays and neutrons. The energy produced is absorbed and stored as heat in a blanket that is then used in a steam thermal cycle to generate electrical power.
There are two methods of compression of the DT pellet: direct and indirect-drive laser fusions.
However, there are a number of limitations to energy production by this process. One limitation is that the process is extremely inefficient in energy energy production. Also, the heat produced by the flashtubes results innthe deformation of the laser glass.
what is the pH value of water
Answer:
The pH of pure water (H20) is 7 at 25oC, but when exposed to the carbon dioxide in the atmosphere this equilibrium results in a pH of approximately 5.2. Because of the association of pH with atmospheric gasses and temperature, it is strongly recommended that the water be tested as soon as possible.
Identify the alkene obtained on dehydration of each of the following alcohols:
a. 3-Ethyl-3-pentanol
b. 1-Propanol
c. 2-Propanol
d. 2,3,3-Trimethyl-2-butanol
Answer:
Explanation:
The information below explains how dehydration of alcohol occurs to produce alkene.
Under the influence of a catalyst, alcohol dehydrates to produce an alkene and water. To produce alkene and water, the reaction eliminates the OH group from alcohol containing the carbon atom and the hydrogen atom from a neighboring carbon atom via the same molecule.
The –OH group in alcohol contribute two(2) electrons to H+ out from the acid reagent, resulting in the formation of an alkyloxonium ion. This ion serves as an excellent leaving group, allowing a carbocation to form. The nucleophile which acts as the deprotonated acid subsequently attacks and creates a double bond with the hydrogen next to the carbocation.
An infant acetaminophen suspension contains 80 mg/0.80 mL suspension. The recommended dose is 15 mg/kg body weight.
How many milliliters of this suspension should be given to an infant weighing 13 lb.
Answer:
0.8853 mL
Explanation:
First we convert 13 lb to kg, keeping in mind that 1 lb = 0.454 kg:
13 lb * [tex]\frac{0.454kg}{1lb}[/tex] = 5.902 kgThen we calculate how many mg of acetaminophen should be given, using the recommended dose and infant mass:
15 mg/kg * 5.902 kg = 88.53 mgFinally we calculate the required mL of suspension, using its concentration:
88.53 mg ÷ (80 mg/0.80 mL) = 0.8853 mLWat are representative elements
Answer:
the representative elements are elements where the the s and p orbitals are filling. The transition elements are elements where the d orbitals (groups 3-11 on the periodic table) are filling, and the inner transition metals are the elements where the f orbitals are filling.
Explanation:
=)
What is the total number of joules released when a 5.00-gram sample of water changes from liquid to solid a 0° C?
What is erosion?
A) Weathered materials staying in one place
B) The movement of weathered materials by wind, water or ice
C) New materials on a land form
Answer:
B. The movement of weathered materials by wind, water or ice.
Perform the calculations and determine the absolute and percent relative uncertainty. Express each answer with the correct number of significant figures.
a. [9.8(±0.3)−2.31(±0.01)]8.5(±0.6)= __________
b. absolute uncertainty: __________
c. absolute uncertainty: _________
d. percent relative uncertainty: ___________
Answer:
Explanation:
Given the equation:
[tex]\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}[/tex]
The absolute uncertainty in a measurement is the term used to describe the degree of inaccuracy.
The first step is to determine the algebraic value on the numerator.
Algebraic value = 9.8 - 231
= 7.49
The absolute uncertainty = [tex]\sqrt{(abs. uncertainty_{v_1})^2+(abs. uncertainty_{v_2})^2}[/tex]
absolute uncertainty = [tex]\sqrt{(0.3)^3 + (0.01)^2}[/tex]
= [tex]\sqrt{0.09 + 0.0001}[/tex]
= 0.300167
∴
[9.8(±0.3) - 2.31(±0.01)] = 7.49(±0.300167)
The division process now is:
[tex]\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}= \dfrac{7.49 (\pm 0.300167)}{8.5 (\pm0.6)}[/tex]
Relative uncertainty = [tex]\dfrac{(\pm 0.300167)}{7.49}\times 100 \ , \ \dfrac{(\pm 0.6) }{8.5} \times 100[/tex]
Relative uncertainty = ±4.007565% , ±7.058824%
[tex]\text{Relative uncertainty} = \sqrt{(4.007565)^2+(7.058824)^2}[/tex]
[tex]\text{Relative uncertainty} = \sqrt{16.06057723+49.82699626}[/tex]
[tex]\text{Relative uncertainty} = \sqrt{65.88757349}[/tex]
[tex]\text{Relative uncertainty} = 8.117116[/tex]
≅ 8%
The algebraic value = [tex]\dfrac{7.49}{8.5}[/tex]
= 0.881176
≅ 0.88
The percentage of the relative uncertainty =[tex]\dfrac{\text{Absolute uncertainty }}{\text{calculated value} }\times 100[/tex]
By cross multiplying:
[tex]\text{Absolute uncertainty} (\%) = \dfrac{\text{relative uncertainty} \times \text{calculated value}}{100}[/tex]
[tex]\text{Absolute uncertainty} (\%) = \dfrac{8.117116\times 0.881176}{100}[/tex]
[tex]\text{Absolute uncertainty} (\%) = 0.0715260[/tex]
[tex]\mathbf{\text{Absolute uncertainty} (\%) \simeq 0.07}[/tex]
Finally:
[tex]\mathbf{\implies \dfrac{[9.8(\pm0.3)-2.31(\pm 0.01)]}{8.5(\pm0.6)}= 0.88 \pm (0.07) \pm 8\%}[/tex]
A buffer solution contains 0.368 M hydrocyanic acid and 0.360 M potassium cyanide . If 0.0513 moles of sodium hydroxide are added to 225 mL of this buffer, what is the pH of the resulting solution
Solution :
Millimoles of hydrocyanic acid = 225 x 0.368
= 82.8
Millimoles of potassium cyanide = 225 x 0.360
= 81
Millimoles of sodium hydroxide = 51.3
Therefore,
pOH = pKb + log [salt - C / bas + C]
= 4.74 + log[82.8 - 51.3 / 81 + 51.3]
= 4.102
Therefore, pH = 9.05
Calculate the molality of a 35.4 % (by mass) aqueous solution of phosphoric acid (H3PO4) (35.4 % means 35.4 g of H3PO4in 100 g of solution)
Answer:
3.6124 m/kg
Explanation:
Molality is calculated as moles of solute (mol) divided by kilogram of solvent (kg). Here, we can find these numbers by using the 35.4%, which gives us 35.4 g of H3PO4 and 100 g of solution to work with.
To go from grams to moles for the phosphoric acid, you need to find the molar mass of the compound or element and divide the grams of the compound or element by that molar mass.
Here, the molar mass for phosphoric acid is 97.9952 g/mol. The equation would look like this:
35.4 g x 1 mol / 97.9952 g = 0.3612422 mol
Next, the 100 g of solvent can easily be converted to 0.1 kg of solvent.
To find the molality, divide the moles of solute and kilograms of solution.
0.3612422 mol / 0.1 kg = 3.6124 m/kg
Compounds containing chlorine have long been used to disinfect the water in swimming pools, but in recent years a compound of a less corrosive halogen has become a popular alternative disinfectant. What is the name of this fourth-row element
Explanation:
A period 4 element is one of the chemical elements in the fourth row (or period) of the periodic table of the elements.
...
Period 4 element.
Hydrogen Rubidium
Strontium
Yttrium
Zirconium
Niobium
To solve this we must be knowing each and every concept related to disinfectant. Therefore, chlorine dioxide is used as alternative disinfectant.
What is disinfectant?A disinfectant is indeed a chemical agent or compound that is used to kill or inactivate germs on inert surfaces. Disinfection may not always destroy all germs, particularly antibiotic resistant spores; it is more successful than sterilization, which involves a harsh physical or chemical procedure that kills all forms of life.
Compounds containing chlorine have long been used to disinfect the water in swimming pools, but in recent years a compound of a less corrosive halogen has become a popular alternative disinfectant. Chlorine dioxide is used as alternative disinfectant.
Therefore, chlorine dioxide is used as alternative disinfectant.
To know more about disinfectant, here:
https://brainly.com/question/28522315
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Note: Please show all work and calculation setups to get full credit. T. he following may be used on this assignment: specific heat of (water=4.184 J/g oC; ice=2.03 J/g oC; steam=1.99 184 J/g oC); heat of fusion of water=80. cal/g; heat of vaporization=540 cal/g; 1cal=4.184J. Calculate the energy required (in J) to convert 25 g of ice at -15 oC to water at 75 oC.
Answer:
Feel free to ask for more AP Chem helps babe <3
what is polarization??
Answer:
I Hope this is clear
Explanation:
Polarization, property of certain electromagnetic radiations in which the direction and magnitude of the vibrating electric field are related in a specified way. polarizing filter.
Answer:
Polarization is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave.
Explanation:
Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations. In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave. A simple example of a polarized transverse wave is vibrations traveling along a taut string (see image); for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string. In contrast, in longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization. Transverse waves that exhibit polarization include electromagnetic waves such as light and radio waves, gravitational waves,[6] and transverse sound waves (shear waves) in solids.
An electromagnetic wave such as light consists of a coupled oscillating electric field and magnetic field which are always perpendicular to each other; by convention, the "polarization" of electromagnetic waves refers to the direction of the electric field. In linear polarization, the fields oscillate in a single direction. In circular or elliptical polarization, the fields rotate at a constant rate in a plane as the wave travels. The rotation can have two possible directions; if the fields rotate in a right hand sense with respect to the direction of wave travel, it is called right circular polarization, while if the fields rotate in a left hand sense, it is called left circular polarization.
Light or other electromagnetic radiation from many sources, such as the sun, flames, and incandescent lamps, consists of short wave trains with an equal mixture of polarizations; this is called unpolarized light. Polarized light can be produced by passing unpolarized light through a polarizer, which allows waves of only one polarization to pass through. The most common optical materials do not affect the polarization of light, however, some materials—those that exhibit birefringence, dichroism, or optical activity—affect light differently depending on its polarization. Some of these are used to make polarizing filters. Light is also partially polarized when it reflects from a surface.
According to quantum mechanics, electromagnetic waves can also be viewed as streams of particles called photons. When viewed in this way, the polarization of an electromagnetic wave is determined by a quantum mechanical property of photons called their spin. A photon has one of two possible spins: it can either spin in a right hand sense or a left hand sense about its direction of travel. Circularly polarized electromagnetic waves are composed of photons with only one type of spin, either right- or left-hand. Linearly polarized waves consist of photons that are in a superposition of right and left circularly polarized states, with equal amplitude and phases synchronized to give oscillation in a plane.
Polarization is an important parameter in areas of science dealing with transverse waves, such as optics, seismology, radio, and microwaves. Especially impacted are technologies such as lasers, wireless and optical fiber telecommunications, and radar.
Fill in the blank to complete the statement
Answer:
I dont get it what words are we using bc I see words on the side just it doesn't make any sense
Gaseous methane CH4 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 0.963 g of methane is mixed with 1.2 g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to 2 significant digits.
Answer:
[tex]m_{H_2O}=0.676gH_2O[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to calculate the maximum mass of water by firstly setting up the undergoing chemical reaction as follows:
[tex]CH_4+2O_2\rightarrow CO_2+2H_2O[/tex]
Thus, we are able to firstly calculate the moles of water produced by both methane and oxygen in order to identify the limiting reactant, which is related to maximum of water:
[tex]0.963 gCH_4*\frac{1molCH_4}{16gCH_4}*\frac{2molH_2O}{1molCH_4} =0.120molH_2O\\\\1.2gO_2*\frac{1molO_2}{32gO_2}*\frac{2molH_2O}{2molO_2} =0.0375molH_2O[/tex]
Thus, we infer the limiting reactant is O2 and therefore we can obtain up to 0.0375 moles of water, which are related to the following mass:
[tex]m_{H_2O}=0.0375molH_2O\frac{18.02gH_2O}{1molH_2O}=0.676gH_2O[/tex]
Regards!
You are an intermediate product of an industrial process which intends to separate iron from its ore. A well known iron ore is hematite. Which of these ores does not contain iron?
Goethite
Malachite
Siderite
Limonite
Answer:
Malachite
Explanation:
Malachite is a copper carbonate hydroxide mineral, with the equation Cu2CO3(OH)2. This dark, green-joined mineral solidifies in the monoclinic precious stone framework, and frequently shapes botryoidal, sinewy, or stalagmitic masses, in cracks and profound, underground spaces, where the water table and aqueous liquids give the way to synthetic precipitation. So, the answer is malachite. Best of Luck!
Emily spills concentrated sodium hydroxide solution on her lab bench. What she should do first?
Answer:
Explanation: hell noo
What would have happened to humankind if technology did not exist?
Diameter of the Balloon
Before Heat
After Heat
6 centimeters 10 centimeters
Which conclusion is supported by the evidence?
A. Air expands when heated.
B. Air is warmer when heated.
C. The balloon will pop when heated.
D. The balloon contracts when heated.
Answer:
A. air expands when heated.
Explanation:
hope this helps!