An isotope is an element with the same atomic number but different mass number due to differences in number of neutrons.
electron configuration is 2,8,6.
Belongs to group 6 and period group 3.
It forms an ion by accepting 2 electrons
How did Kepler's discoveries contribute to astronomy?
O They supported the heliocentric model.
O They established the laws of planetary motion.
O They explained how the Sun rises and sets.
O They made astronomy accessible to people who spoke Italian.
They made astronomy accessible to people who spoke italian
Answer:
"They established the laws of planetary motion"
Explanation:
Mr. Kepler was the astronomer who came up with the "Laws of Planetary Motion."
if an element has an atomic number of 9 what is the electronic structure of the same element
9 is the element Florine
Florine has 9 electrons as well as the 9 protons that determine its atomic number.
The ground state configuration is the lowest energy configuration.
Which chemical can remove color of red/Pink phenol and make it clear like water transparent?
balance equation of aluminium chloride+ hydrogen
[tex]\boxed{\sf {AlCl_3\atop Aluminium\:Chloride}+{H_2\atop Hydrogen}\longrightarrow {Al\atop Aluminium}+{HCl\atop Hydrochloric\:acid}}[/tex]
Balanced Equation:-
[tex]\boxed{\sf {2AlCl_3\atop Aluminium\:Chloride}+{3H_2\atop Hydrogen}\longrightarrow {2Al\atop Aluminium}+{6HCl\atop Hydrochloric\:acid}}[/tex]
You need to make an aqueous solution of 0.182 M aluminum sulfate for an experiment in lab, using a 250 mL volumetric flask. How much solid aluminum sulfate should you add
Answer:
Hence, 15.99 g of solid Aluminum Sulfate should be added in 250 mL of Volumetric flask.
Explanation:
To make 0.187 M of Aluminum Sulfate solution in a 250 mL (0.250 L) Volumetric flask
The molar mass of Aluminum Sulfate = 342.15 g/mol
Using the molarity formula:-
Molarity = Number of moles/Volume of solution in a liter
Number of moles = Given weight/ molar mass
Molarity = (Given weight/ molar mass)/Volume of solution in liter
0.187 M = (Given weight/342.15 g/mol)/0.250 L
Given weight = 15.99 g
How is the rate of a reaction affected when the temperature increases?
A. The rate decreases because the reactant particles move too
quickly to react.
B. The rate increases because the equilibrium constant increases.
C. The rate increases because the reactant particles collide more
often.
D. The rate decreases because the products reform the reactants more quickly
more quickly.
The rate of reaction increases when the temperature increases because the reactant particles collide more often and the correct option is option C.
What is Rate of reaction?
The rate of reaction refers to the speed at which the products are formed from the reactants in a chemical reaction. It gives some insight into the time frame under which a reaction can be completed.
The rate or speed of reaction can be defined as the change in the concentration of any one of the reactants or products per unit time.
The rate is higher at higher temperatures because colliding particles will have the required activation energy at high temperature and more successful collisions will take place.
Therefore, The rate of reaction increases when the temperature increases because the reactant particles collide more often and the correct option is option C.
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What is the percentage by mass of carbon in CH3(CH2)5COOH?
A. 48.6%
B. 9.2%
C. 55.4%
D. 64.6%
Answer:
F 64.6 percent of carbon may be
Determine the value of the equilibrium constant for the following reaction, where the following amounts of each species are present at equilibrium in a 5.00 L container: 1.34 mol HCl, 4.30 mol O2, 30 g H2O, and 2.42 mol Cl2.
4 HCl(g) O2(g) ----> 2 H2O(l) 2 Cl2(g)
Explanation:
here's the answer to your question about
12.39 HBr can be added to alkenes in either the absence or presence of peroxides (producing either the Markovnikov or the anti-Markovnikov addition product). What intermediates leading to the formation of the major product are observed when 1-butene is treated with 1) HBr or 2) HBr/peroxides
Answer:
See explanation and image attached
Explanation:
The reaction of HBr with 1-butene is an addition reaction. The HBr adds across the double bond to yield a saturated halogenoalkane.
In the absence of peroxides, the reaction proceeds in accordance with Markovnikov rule which states that;''the negative part of the addendum, is attached to the carbon atom with the least number of hydrogen atoms attached.'' This occurs in the first reaction shown in the image.
In the presence of peroxides, the reaction proceeds in an anti-Markovnikov manner to yield the product shown in the second reaction.
What is the molecular formula of following show how it is done.1 nitric acid 2 Sulphuric acid 3 Methane 4 Potassium oxide 5 Silver chloride 6 Limestone . Answer it ASAP.Thank u
Answer:
1.HNO₃
Nitric acid is a nitrogen oxoacid of formula HNO3 in which the nitrogen atom is bonded to a hydroxy group and by equivalent bonds to the remaining two oxygen atoms.
2.H₂SO₄
3.CH₄
Methane (US: , UK: ) is a chemical compound with the chemical formula CH4 (one atom of carbon and four atoms of hydrogen). It is a group-14 hydride and the simplest alkane and is the main constituent of natural gas.
4.K₂O
5.AgCl
6.CaCO3
Limestone consists of calcium carbonate, which has the chemical formula CaCO3. Limestone exists in sedimentary and crystalline form.
Explanation:
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The graph below shows how the temperature and volume of a gas vary when
the number of moles and the pressure of the gas are held constant. What
happens to the
temperature of a gas as its volume increases?
A. The temperature decreases
B. The temperature increases
C. The temperature remains the same.
D. The temperature doubles.
Answer:
C
Explanation:
because it remains the same
An equilibrium mixture of PCl5(g), PCl3(g), and Cl2(g) has partial pressures of 217.0 Torr, 13.2 Torr, and 13.2 Torr, respectively. A quantity of Cl2(g) is injected into the mixture, and the total pressure jumps to 263.0 Torr at the moment of mixing. The system then re-equilibrates. The chemical equation for this reaction is
Answer:
p'PCl3 = 6.8 torr
p'Cl2 =26.4 torr
p'PCl5 =223.4 torr
Explanation:
An equilibrium mixture of PCl5(g), PCl3(g), and Cl2(g) has partial pressures of 217.0 Torr, 13.2 Torr, and 13.2 Torr, respectively. A quantity of Cl2(g) is injected into the mixture, and the total pressure jumps to 263.0 Torr at the moment of mixing. The system then re-equilibrates. The chemical equation for this reaction is
PCl3(g) + Cl2(g) ---> PCl5(g)
Calculate the new partial pressures after equilibrium is reestablished. [in torr]
pPCl3
pCl2
pPCl5
Step 1: Data given
Partial pressure before adding chlorine gas:
Partial pressure of PCl5 = 217.0 torr
Partial pressureof PCl3 = 13.2 torr
Partial pressureof Cl2 = 13.2 torr
A quantity of Cl2(g) is injected into the mixture, and the total pressure jumps to 263.0 Torr at the moment of mixing
Step 2: The equation
PCl3(g)+Cl2(g) ⇔ PCl5(g)
Step 3: The expression of an equilibrium constant before adding chlorine gas
Kp = pPCl5 / (pPCl3 * pCl2)
Kp = 217.0 / (13.2 * 13.2)
Kp = 1.245
Step 4: The expression of an equilibrium constant after adding chlorine gas
Partial pressure of PCl5 = 217.0 torr
Partial pressure of PCl3 = 13.2
Partial pressure of Cl2 = TO BE DETERMINED
Step 5: The total pressure of the system
Ptotal = pPCl5 + pPCl3 + pCl2
263.0 torr = 217.0 torr + 13.2 torr + pCl2
pCl2 = 263.0 - 217.0 -13.2 = 32.8 torr
Step 6: The initial pressure
The equation: PCl3(g)+Cl2(g) ⇔ PCl5(g)
pPCl3 = 13.2 torr
pCl2 = 32.8 torr
pPCl5 = 217.0 torr
Step 7: The pressure at the equilibrium
p'PCl3 = (13.2 -x) torr
p'Cl2 = (32.8 - x) torr
p'PCl5 = (217.0 + x) torr
Step 8: The equilibrium constant
'Kp = p'PCl5 / (p'PCl3 * p'Cl2)
1.245 = (217.0+x) / ((13.2-x)(32.8-x)
x = 6.40 torr
p'PCl3 = 13.2 -6.40 = 6.8 torr
p'Cl2 = 32.8 - 6.40 =26.4 torr
p'PCl5 = 217.0 + x) 6.4 = 223.4 torr
Calculate the pH of each solution.
A. 0.18 M CH3NH2
B. 0.18 M CH3NH3Cl
C. a mixture of 0.18 M CH3NH2 and 0.18 M CH3NH3Cl
Answer:
See Explanations
Explanation:
pH =-log[H₃O⁺] = -log[H⁺]
pOH = -log[OH⁻]
For weak acids [H⁺] = SqrRt(Ka·[Acid])
For weak bases [OH⁻] = SqrRt(Kb·[Base])
pH + pOH = 14
__________________________________________
A. Given 0.18M CH₃NH₂; Kb = (4.4 x 10⁻⁴)* => pH = 11.95
CH₃NH₂ + H₂O => CH₃NH₃OH ⇄ CH₃NH₃⁺ + OH⁻;
[OH⁻] = SqrRt(Kb·[weak base]) = SqrRt(4.4 x 10⁻⁴ x 0.18)M = 8.97 x 10⁻³M
=> pOH = -log[OH⁻] = -log(8.93x10⁻³) = -(-2.05) = 2.05
=> pH = 14 - pOH = 14 - 2.05 = 11.95.
*Kb values for most ammonia derivatives in water can be found online by searching 'Kb-values for weak bases'. Kb-values for methyl amine and methylammonium chloride are both 4.4x10⁻⁴.
___________________________________________________
B. Given 0.18M CH₃NH₃Cl
In water ... CH₃NH₃Cl => CH₃NH₃⁺ + Cl⁻; Kb(CH₃NH₃Cl) = 4.4 x 10⁻⁴
Cl⁻ + H₂O => No Rxn (i.e.; no hydrolysis occurs) ... Cl⁻ does not react with H₂O.
Hydrolysis Reaction of Methylammonium Ion:
CH₃NH₃⁺ + H₂O => CH₃NH₄OH ⇄ CH₃NH₄⁺ + OH⁻
Ka' x Kb = Kw => Ka' = Kw/Kb = 10⁻¹⁴/4.4 x 10⁻⁴ = 2.27 x 10⁻¹¹ Ka' = [CH₃NH₄⁺][OH⁻]/[CH₃NH₄OH] = (x)(x)/(0.18M) = (x²/0.18M) = 2.27 x 10⁻¹¹ => x = [OH⁻] = SqrRt(2.27x10⁻¹¹ x 0.18)M = 2.02 x 10⁻⁶M => pOH = -log(2.02 x 10⁻⁶) = -(-5.69) = 5.69 => pH = 14 - pOH = 14 - 5.69 = 8.31.
*note => the general nature of halide interactions would increase acidity (lower pH) of the halogenated compound.
C. A mixture of 0.18M CH₃NH₂ and 0.18M CH₃NH₃Cl
Mixture of 0.18M CH₃NH₂ + 0.18M CH₃NH₃Cl
In Water ...
=> 0.18M CH₃NH₃OH + 0.18M CH₃NH₃Cl
=> 0.18M CH₃NH₃⁺ + 0.1M OH⁻ + 0.18M CH₃NH₃⁺ + 0.18M Cl⁻
=> 0.36M CH₃NH₃⁺ + 0.18M OH⁻ + 0.18M Cl⁻
-----------------------------------------------------------
Ka'(CH₃NH₃⁺) x Kb(CH₃NH₂) = Kw => Ka'(CH₃NH₃⁺) = Kw/Kb(CH₃NH₂)
=> Ka'(CH₃NH₃⁺) = (10⁻¹⁴/4.4x10⁻⁴) = 2.27x10⁻¹¹
----------------------------------------------------------
From the 0.36M CH₃NH₃⁺
=> CH₃NH₃⁺ + H₂O ⇄ CH₃NH₄⁺ + OH⁻
C(eq) 0.36M ---- x x (<= at equilibrium after mixing)
Ka'(CH₃NH₃⁺) = [CH₃NH₄⁺][OH⁻]/[CH₃NH₃⁺] = x²/(0.36M)
=> x = [OH⁻] = SqrRt(Ka'(CH₃NH₃⁺)·0.36M) = SqrRt(2.27x10⁻¹¹/0.36) = 0.0126M
=> Total [OH⁻] = 0.0126M + 0.18M = 0.1926M from hydrolysis process
=> final solution mix is therefore, 0.1926M in OH⁻ + 0.18M in Cl⁻
--------------------------------------------------------
Cl⁻ + H₂O => No Rxn (Cl⁻ does not react with H₂O)The 0.1926M in OH⁻ => [H⁺] = Kw/[OH⁻] = (10⁻¹⁴/0.1926)M = 5.192 x 10⁻¹⁴M in H₃O⁺ ions (= H⁺ ions) ...∴pH = -log[H⁺] = -log(5.192x10⁻¹⁴) = -(-13.29) = 13.29 for solution mix
The acid and base dissociation constant and the 0.18 M of CH₃NH₂ and
CH₃NH₃Cl and the mixture give the following approximate values;
A. The pH value of the 0.18 M CH₃NH₂ is 11.93
B. The pH value of the 0.18 M CH₃NH₃Cl is 5.69
C. The pH value of the mixture is 10.644
Which method can be used to calculate the pH values?A. 0.18 M CH₃NH₂
The solution is presented as follows;
CH₃NH₂ + H₂O → CH₃NH₃⁺ + OH⁻
Let x represent the number of moles of CH₃NH₃⁺ and OH⁻ produced, we
have;
The number of moles of CH₃NH₂ remaining = 0.18 - x
Which gives;
[tex]K_b = \mathbf{\dfrac{[CH_3NH_3^+][OH^-]}{[CH_3NH_2]}}[/tex]
[tex]K_b[/tex] for CH₃NH₂ = 4.167 × 10⁻⁴
Therefore;
[tex]4.167 \times 10^{-4} = \mathbf{\dfrac{x \times x}{0.18 - x}}[/tex]
4.167 × 10⁻⁴ × (0.18 - x) = x²
4.167 × 10⁻⁴ × (0.18 - x) - x² = 0
Which gives;
x = [OH⁻] = 8.455 × 10⁻³
pH = 14 + log[OH⁻]
Which gives;
pH = 14 + log(8.455 × 10⁻³) ≈ 11.93
B. 0.18 M CH₃NH₃Cl
The solution is presented as follows;
CH₃NH₃⁺ → CH₃NH₂ + H⁺
Let x represent the number of moles of CH₃NH₂ and H⁺ produced,
respectively, we have;
The number of moles of CH₃NH₃⁺ remaining = 0.18 - x
Which gives;
[tex]K_a = \mathbf{\dfrac{[CH_3NH_2][H^+]}{[CH_3NH_3^+]}}[/tex]
Kₐ for CH₃NH₃Cl = 2.27 × 10⁻¹¹
Therefore;
[tex]2.27\times 10^{-11} = \dfrac{x \times x}{0.18 - x}[/tex]
2.27 × 10⁻¹¹ × (0.18 - x) = x²
2.27 × 10⁻¹¹ × (0.18 - x) - x² = 0
Which gives;
x = [H⁺] ≈ 2.02 × 10⁻⁶
pH = -log[H⁺]
Which gives;
pH = -log(2.02 × 10⁻⁶) ≈ 5.69
C. For the mixture of 0.18 M CH₃NH₂ and 0.18 M of CH₃NH₃Cl, we have;
Based on the Henderson-Hasselbalch equation, we have;
[tex]pH = \mathbf{ pKa + log\dfrac{[Conjugate \ base]}{[acid ]}}[/tex]
Which gives;
[tex]pH = -log\left(2.27 \times 10^{-11} \right)+ log\dfrac{0.18}{0.18} \approx \underline{10.644}[/tex]
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NCEPT The mass of NaClcontaining the Avogadro Number of particles is.
Answer:
one mole of water (6.022 x 10 23 molecules) has a mass of 18.02 g. One mol of NaCl (6.02 x1023 formulas) has a mass of 58.44 g.
Explanation:
• The mole (or mol) represents a certain number of objects.
• SI def.: the amount of a substance that contains the same
number of entities as there are atoms in 12 g of carbon-12.
• Exactly 12 g of carbon-12 contains 6.022 x 10 23 atoms.
• One mole of H 2O molecules
contains 6.022 x 10 23 molecules.
• 1 mole contains 6.022 x 10 23 entities (Avogadro’s number)
• One mole of NaCl contains 6.022 x 10 23 NaCl formula units.
• Use the mole quantity to count formulas by weighing them.
• Mass of a mole of particles = mass of 1 particle x 6.022 x 1023
Mass of 1 H atom: 1.008 amu x 1.661 x10-24 g/amu = 1.674 x10-24 g
Mass of 1 mole of H atoms:
1.674 x10-24g/H atom x 6.022 x1023H atoms = 1.008 g
• The mass of an atom in amu is numerically the same
as the mass of one mole of atoms of the element in grams.
• One atom of sulfur has a mass of 32.07 amu;
one mole of S atoms has a mass of 32.07 g
Calculate the mass of water produced when 7.49 g of butane reacts with excess oxygen.
Answer:
[tex]m_{H_2O}=12.9gH_2O[/tex]
Explanation:
Hey there!
In this case, according to the given information, it turns out possible for us to solve this problem by firstly writing out the reaction whereby butane is combusted in the presence of excess oxygen:
[tex]2C_4H_{10}+13O_2\rightarrow 8CO_2+10H_2O[/tex]
Thus, we can evidence a 2:10 mole ratio of butane to water, and thus, the stoichiometric setup to calculate the mass of produced water is:
[tex]m_{H_2O}=7.49gC_4H_{10}*\frac{1molC_4H_{10}}{52.12gC_4H_{10}} *\frac{10molH_2O}{2molC_4H_{10}}*\frac{18.02gH_2O}{1molH_2O}\\\\m_{H_2O}=12.9gH_2O[/tex]
Regards!
Which one of these statements is/are true: I. All redox reactions with positive emfs are spontaneous. II. If a redox reaction is spontaneous, it must be fast. III. A spontaneous redox reaction will have a cathode reaction that has a more negative reduction potential than the anode. III only. I and III are true. I only. II only. All of I, II, and III are true.
Answer:
yea all the answers are true
Redox reaction is the transfer of the electron from one species to another. All of the three statements are true about the redox reaction.
What is a redox reaction?A redox reaction is a type of chemical reaction in which the electrons are gained and lost by a species. The positive EMF of the cell results in spontaneous and will move the reaction in the forward direction.
In a redox reaction, the cathode reaction is comparatively more negative than the reduction potential present at the anode.
Therefore, option E. All I, II, and III are true.
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The products of nuclear reaction usually have a different mass than the reactants why?
Answer:
Explanation:
The best way to explain this is to use an example
[tex]I\frac{125}{53} + e \frac{0}{-1} ====> Te\frac{125}{52}[/tex]
You have to understand what happened. A electron was shot into the nucleus of the Iodine. That electron change the entire composition of the nucleus resulting in 52 protons. The mass remained the same (125) but the nucleus was altered. The chemical became 125 52 Tellurium. But what is important is that it takes a tremendous amount of energy to disrupt a nucleus, and a new chemical is born from that disruption.
1. Metallic strontium crystallizes in a face-centered cubic lattice, with one Sr atom per lattice point. If the edge length of the unit cell is found to be 608 pm, what is the metallic radius of Sr in pm?
2. The substance beta manganese is found to crystallize in a cubic lattice, with an edge length of 630.0 pm. If the density of solid beta manganese is 7.297 g/cm3, how many Mn atoms are there per unit cell?
Answer:
[tex]r=215pm[/tex]
[tex]N_{Mn}=20[/tex]
Explanation:
From the question we are told that:
Edge length of the unit cell [tex]l=608pm[/tex]
a)
Generally the equation for The relationship between edge length and radius is mathematically given by
[tex]4r=\sqrt{2a}[/tex]
Therefore
[tex]4r=\sqrt{2*608}[/tex]
[tex]r=\frac{\sqrt{2*608}}{4}[/tex]
[tex]r=215pm[/tex]
b)
From the question we are told that:
Density [tex]\rho=7.297[/tex]
Edge length of [tex]l=630.0 pm=>630*10^-{10}[/tex]
Therefore Volume is given as
[tex]V=l^3[/tex]
[tex]V=630*10^-{10}^3[/tex]
[tex]V=2.50047*10^{−22}[/tex]
Generally the equation for Mass is mathematically given by
[tex]m=Volume*density[/tex]
[tex]m=V*\rho[/tex]
[tex]m=2.50047*10^{−22}*7.297[/tex]
[tex]m=1.83*10^{-21}g[/tex]
Therefore Molarity is given as
[tex]n=\frac{M}{Molar M}[/tex]
[tex]n=\frac{1.83*10^{-21}g}{55}[/tex]
[tex]n=3.32*10^{-23}[/tex]
Finally The atoms in a unit cell is
[tex]N_{Mn}=Moles*Avogadro\ constant[/tex]
[tex]N_{Mn}=3.32*10^{-23}*6.023*10^{23}[/tex]
[tex]N_{Mn}=20[/tex]
A reaction rate increases by a factor of 500. in the presence of a catalyst at 37oC. The activation energy of the original pathway is 106 kJ/mol. What is the activation energy of the new pathway, all other factor being equal
Answer:
[tex]E_2=999984KJ/mole[/tex]
Explanation:
From the question we are told that:
Factor [tex]dK=500[/tex]
Temperature [tex]T=37 C=310k[/tex]
Activation energy [tex]E=10^6kJ/mol[/tex]
Generally the Arhenius equation is mathematically given by
[tex]ln \frac{K_2}{K_1}=\frac{ E_1-E_2}{RT}[/tex]
Where
[tex]\frac{K_2}{K_1}=500[/tex]
[tex]ln 500=\frac{ 10^6-10^3-E_2}{8.314*310}[/tex]
[tex]E_2=999984KJ/mole[/tex]
The activation energy of the new reaction is 105.99 kJ/mol.
Using the Arrhenius equation;
ln(k2/k1) = -Ea2/RT2 + Ea1/RT1
Now, from the information in the question;
k2/k1 = 500
Ea = ?
R = 8.314 JKmol-1
T2 = 37oC + 273 = 310 K
T1 = 37oC + 273 = 310 K
Substituting values;
ln (500) =- Ea2 + Ea1
6.2 = -Ea2 + 106 × 10^3 J
Ea = 106 × 10^3 J - 6.2
Ea = 105.99 × 10^3 J or 105.99 kJ/mol
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Calculate the molarity of a solution consisting of 65.5 g of K2S0 4 in 5.00 L of solution.
Answer:
Molarity is 0.075 M.
Explanation:
Moles:
[tex]{ \tt{ = \frac{65.5}{RFM} }}[/tex]
RFM of potassium sulphate :
[tex]{ \tt{ = (39 \times 2) + 32 + (16 \times 4)}} \\ = 174 \: g[/tex]
substitute:
[tex]{ \tt{moles = \frac{65.5}{174} = 0.376 \: moles}}[/tex]
In volume of 5.00 l:
[tex]{ \tt{5.00 \: l = 0.376 \: moles}} \\ { \tt{1 \: l = ( \frac{0.376}{5.00} ) \: moles}} \\ { \tt{molarity = 0.075 \: mol \: l {}^{ - 1} }}[/tex]
calculate the hydrogen ion concentration of a solution who's pH is 2.4
Answer:
I don't know sorry yyyyyyy6yyyyyyyyyyyyyyyyyyyyyyyyyyy
I don’t know what Ksp and Kf are stand for?
Answer:
Sorry but I know only what ksf stand for
Explanation:
Ksf stand for solubility product constant
Answer:
ksp stands for solubility product constant .
kf stands for molal freezing point depression constant ..
Explanation:
KSP = The solubility product constant, Ksp, is the equilibrium constant for a solid substance dissolving in an aqueous solution. It represents the level at which a solute dissolves in solution. The more soluble a substance is, the higher the Ksp value it has .
KF = Kf is a constant for a given solvent. Kf is called the molal freezing point depression constant and represents how many degrees the freezing point of the solvent will change when 1.00 mole of a nonvolatile nonionizing (nondissociating) solute dissolves in one kilogram of solvent.
Avogradro's number is the number of particles in one gram of carbon- 12 atom true or false?
Answer:
True
Explanation:
The value of the mole is equal to the number of atoms in exactly 12 grams of pure carbon-12. 12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms • The number of particles in 1 mole is called Avogadro's Number (6.0221421 x 1023).
State the different radiations emitted by radioactive elements.
The Ka for acetic acid (HC2H3O2) is 1.80 x 10-5 . Determine the pH of a 0.0500mol/L acetic acid solution.
I have no idea how to approach this, so If you have the answer for it, please respond as soon as you can
Answer:
pH = 3.02
Explanation:
Acetic Acid is a weak acid (HOAc) that ionizes only ~1.5% as follows:
HOAc ⇄ H⁺ + OAc⁻.
In pure water the hydronium ion concentration [H⁺] equals the acetate ion concentration [OAc⁻] and can be determined* using the formula [H⁺] = [OAc⁻] = SqrRt(Ka·[acid]) = SqrRt(1.8x10⁻⁵ x 0.0500)M = 9.5x10⁻⁴M.
By definition, pH = -log[H⁺] = -log(9.5x10⁻⁴) = 3.02
______________________________________________________
*This formula can be used to determine the [H⁺] & [Anion⁻] concentrations for any weak acid in pure water given its Ka-value and the molar concentration of acid in solution.
Given the following reaction:
CO (g) + 2 H2(g) <==> CH3OH (g)
In an experiment, 0.42 mol of CO and 0.42 mol of H2 were placed in a 1.00-L reaction vessel. At equilibrium, there were 0.29 mol of CO remaining. Keq at the temperature of the experiment is ________.
A) 2.80
B) 0.357
C) 14.5
D) 17.5
E) none of the above
Answer:
Option D. 17.5
Explanation:
Equiibrium is: CO + 2H₂ ⇄ CH₃OH
1 mol of CO is in equibrium with 2 moles of hydrogen in order to make, methanol.
Initially we have 0.42 moles of CO and 0.42 moles of H₂
If 0.29 moles of CO remained, (0.42 - 0.29) = 0.13 moles have reacted.
So in the equilibrium we may have:
0.29 moles of CO, and (0.42 - 0.13 . 2) = 0.16 moles of H₂
Ratio is 1:2, if 0.13 moles of CO haved reacted, (0.13 . 2) moles have reacted of hydrogen
Finally 0.13 moles of methanol, are found after the equilibrium reach the end.
Let's make expression for KC: [Methanol] / [CO] . [Hydrogen]²
0.13 / (0.29 . 0.16²)
Kc = 17.5
You are titrating 24.3 mL of 2.00 M HCl with 1.87 M NaOH. How much NaOH do you expect to have added when you reach the equivalence point?
26.0 mL
15.4 mL
13.4 mL
Answer:
26mL
Explanation:
NaOH+HCl= NaCl+H2O
nHCl=0.0243*2=0.0486
nNaOh=nHCl
VNaOH=0.0486/1.87=0.026l=26ml
Answer:
26.0 mL
Explanation:
At what velocity (m/s) must a 20.0g object be moving in order to possess a kinetic energy of 1.00J
Answer:
10 ms-1
Explanation:
Kinetic energy = 1/2 × m × v^2
1 = 1/2× 20 ×10^ -3 × v^2
v ^ 2 = 100
v = 10 ms-1
note : convert grams in to kg before substitution as above
Given:
Kinetic energy,
K.E = 1.00 JMass,
m = 20.0 gWe know the formula,
→ [tex]K.E = \frac{1}{2} mv^2[/tex]
By putting the values, we get
[tex]1 = \frac{1}{2}\times 20\times 10^{-3}\times (v)^2[/tex]
[tex]v^2 = 100[/tex]
[tex]v = \sqrt{100}[/tex]
[tex]v = 10 \ m/s[/tex]
Thus the above response is correct.
Learn more about K.E here:
https://brainly.com/question/24997625
Which are the following exothermic or endothermic
Absorbs Energy
-Hrxn
+Hrxn
Feels Hot
Heat flows from surrounds to Reaction
Not Energetically Favorable
Energetically Favorable
Releases Energy
Feels Cold
Heat flows from the reaction to the surrounds
Answer:
Explanation:
Your mom
Kevin's supervisor, Jill, has asked for an update on today's sales. Jill is pretty busy moving back and forth between different store locations. How can Kevin most effectively deliver an update to her? a) Send a detailed email Send a detailed text message Oc) Book a one-hour meeting for tomorrow morning O d) Call with a quick update
Kevin can effectively deliver an update by sending a detailed EMAIL to Jill
Email, which means electronic mail is a technological advanced way of passing information from persons to persons without physical contact. Sending emails are also official ways of passing vital information regarding business, work to and fro. According to this question, Jill is a very busy supervisor who hardly. The best way for Kevin to deliver any update concerning the store he is managing is to send Jill an updated email that can even be assessed outside work hours. Learn more: https://brainly.com/question/7098974