Answer:
The pH change is 0.22.
Explanation:
The pKa of the buffer NaHCO3/Na2CO3 is 10.329. To find the pH of this buffer we can use H-H equation:
pH = pKa + log [Na2CO3] / [NaHCO3]
Where pH is the pH of the buffer, pKa is 10.329 and [] could be taken as the moles of each specie.
As the initial volume of the buffer is 1.00L, the initial moles are:
[Na2CO3] = 0.246mol
[NaHCO3] = 0.329mol
Initial pH is:
pH = 10.329 + log [0.246mol] / [0.329mol]
pH = 10.20
The KOH reacts with NaHCO3 as follows:
NaHCO3 + KOH → NaKCO3 + H2O
Where NaKCO3≅ Na2CO3. That means the moles added of KOH are the increasing in moles of KOH and the moles of NaHCO3 that decreases.
Thus, moles after the addition of KOH are:
[Na2CO3] = 0.246mol + 0.072mol = 0.318mol
[NaHCO3] = 0.329mol - 0.072mol = 0.257mol
And pH is:
pH = 10.329 + log [0.318mol] / [0.257mol]
pH = 10.42
The pH change is:
10.42 - 10.20 =
0.22
A student dissolves of glucose in of a solvent with a density of . The student notices that the volume of the solvent does not change when the glucose dissolves in it. Calculate the molarity and molality of the student's solution. Round both of your answers to significant digits. molarity molality
Answer:
0.052 M
0.059 m
Explanation:
There is some missing info. I think this is the complete question.
A student dissolves 4.6 g of glucose in 500 mL of a solvent with a density of 0.87 g/mL. The student notices that the volume of the solvent does not change when the glucose dissolves in it. Calculate the molarity and molality of the student's solution. Round both of your answers to 2 significant digits.
Step 1: Calculate the moles of glucose (solute)
The molar mass of glucose is 180.16 g/mol.
4.6 g × 1 mol/180.16 g = 0.026 mol
Step 2: Calculate the molarity of the solution
0.026 moles of glucose are dissolved in 500 mL (0.500 L) of solution. We will use the definition of molarity.
M = moles of solute / liters of solution
M = 0.026 mol / 0.500 L = 0.052 M
Step 3: Calculate the mass corresponding to 500 mL of the solvent
The solvent has a density of 0.87 g/mL.
500 mL × 0.87 g/mL = 435 g = 0.44 kg
Step 4: Calculate the molality of the solution
We will use the definition of molality.
m = moles of solute / kilograms of solvent
m = 0.026 mol / 0.44 kg = 0.059 m
Study the reaction.
CH4 + 2O2 → CO2 + 2H2O
If 7.4 moles of carbon dioxide (CO2) form at the end of the reaction, how many moles of methane (CH4) and oxygen gas (O2) entered the reaction?
? moles of methane and
? moles of oxygen gas
7.4 moles of methane (CH₄)
14.8 moles of oxygen gas (O₂)
What would the products be for the reaction between Na3PO4 + MgSO4?
MgSO4 + Na3PO4 = Na2SO4 + Mg3(PO4)2
Answer: The products of Na3PO4 + MgSO4 are Na2SO4 + Mg3(PO4)2
Explanation:
What is the ratio of 48% carbon 8% hydrogen and 28% nitrogen and 16% oxygen
Answer:
45%
Explanation:
g The following equation is given for the dissociation of the complex ion Ag(NH3) 2. The dissociation constant, Kd, is the equilibrium constant for the dissociation of a complex ion into its component ions. What would be the expression for the dissociation constant of Ag(NH3) 2.
Answer:
Kd = [Ag⁺] × [NH₃]² / [Ag(NH₃)₂⁺]
Explanation:
Let's consider the dissociation reaction of the complex ion Ag(NH₃)₂⁺.
Ag(NH₃)₂⁺(aq) ⇄ Ag⁺(aq) + 2 NH₃(aq)
The dissociation constant, Kd, is the equilibrium constant for the dissociation of the complex ion, that is, it is equal to the product of the concentrations of the products raised to their stoichiometric coefficients divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients.
The dissociation constant for this reaction is:
Kd = [Ag⁺] × [NH₃]² / [Ag(NH₃)₂⁺]
In strong acidic solutions, soaps are converted to
A. Carboxylic acids and a conjugate base
B. Fatty salts and a conjugate
C. I don’t know, hamburgers
D. Carboxylic acids and a conjugate acid
E. Ester and conjugate acid
F. Carbonyl acids and a conjugate base
G. Bubbles and a conjugate
Which example of weathering includes a chemical change
Answer:
Carbonation
Explanation:
An example of weathering which includes a chemical change is that of carbonation.
What is a chemical change?Chemical changes are defined as changes which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical change.
There are several characteristics of chemical changes like change in color, change in state , change in odor and change in composition . During chemical change there is also formation of precipitate an insoluble mass of substance or even evolution of gases.
There are three types of chemical changes:
1) inorganic changes
2)organic changes
3) biochemical changes
During chemical changes atoms are rearranged and changes are accompanied by an energy change as new substances are formed.
Learn more about chemical change,here:
https://brainly.com/question/23693316
#SPJ6
For most solid solutes, what happens to the solubility as temperature increases?
Answer:
For many solids dissolved in liquid water, the solubility increases with temperature. The increase in kinetic energy that comes with higher temperatures allows the solvent molecules to more effectively break apart the solute molecules that are held together by intermolecular attractions.
How many moles of Carbon can be made from 6.37 moles of Iron?
Answer:
Percent yield = 57.7 %Explanation:
An experimental measurement was taken of 10.4mL and the actual measurement was 9.7mL. What is the percent error?
Answer:
13%
Explanation:
I nned help with help plssssss
Answer:
11
Explanation:
3 + 8 = 11
20 character minimum, here you go.
The cation that has the same number of electrons (isoelectronic) as Ne is
None of the listed options
O Na
Mg 2-
All of the listed options
O AI 3-
Which substance is the best oxidizing agent?
A. NaOH
B. H2O
C. Xe
D. HCI
E. O3
Answer:
the answer is A.
Explanation:
Elemental fluorine, for example, is the strongest common oxidizing agent.
All + HgCl, --------> AICI,
-AICI, + Hgl, balance equation then solve the problem
What mass, in grams, of All, is consumed when 138 grams of Hgl, is
produced? *
please help
Answer:
64.7g
Explanation:
The balanced chemical equation of this question is as follows;
AlI + HgCl2 → HgI + AlCl2
Based on the above equation, 1 mole of AlI (aluminum monoiodide) reacts to produce 1 mole of HgI (mercury iodide).
Using mole = mass/molar mass to convert mass of HgI to moles.
Molar mass of HgI = 200.59 + 127
= 327.59g/mol
Mole = 138/327.59
= 0.42mol
- If 1 mole of AlI (aluminum monoiodide) reacts to produce 1 mole of HgI (mercury iodide)
- Then 0.42 mol of HgI will be produced by 0.42mol of AlI.
Using mole = mass/molar mass
Mass = mole × molar mass
Molar mass of AlI = 27 + 127
= 154g/mol
Mass of AlI = 0.42 × 154
= 64.7g of AlI
what do adamantium,vibranium and unobtainum have in common
Answer:
they're all fake
Explanation:
Which organic compound listed below does not have a carbonyl group ?
A. Aldehyde
B. Ketone
C. Ethers
D. Protein
E. Ester
F. Amides
A 0.125 g sample of unknown hydrocarbon is prepared for combustion analysis. After the hydrocarbon undergoes complete combustion, 0.4225 g of CO2 and 0.0865 g of H2O are produced. What is the empirical formula of the unknown
Answer:
Empirical formula is CH
Explanation:
A hydrocarbon, CₐHₓ reacts with oxygen in the combustion reaction as follows:
CₐHₓ + O₂ → a CO₂ + x/2 H₂O
That means we can find the moles of C and H from the moles of CO2 and H2O. As empirical formula is defined as the simplest whole-number ratio of atoms in a molecule, we can determine it as follows:
Moles CO2 = Moles C -Molar mass: 44.01g/mol:
0.4225g * (1mol / 44.01g) = 0.0096 moles C
Moles H2O -Molar mass: 18.01g/mol:
0.0865g H2O * (1mol / 18.01g) = 0.0048moles H2O * (2mol H / 1mol H2O) =
0.0096 moles H
The ratio of atoms of C:H is:
0.0096moles C / 0.0096moles H = 1
That means empirical formula is CH
Given the reaction:
2Al + 6HCI
2AlCl3 + 3H2
If 216 grams of Al was reacted, how many grams of H2 are produced
A 24 grams
B 6 grams
C 12 grams
D48 grams
Answer:
B = 6 grams
Explanation:
please make me brainlist answer
when Mn2 ions are separated from the mixture, they go through a series of oxidizing and reducing steps. Write the reaction equations that describe this process
Answer: hello some part of your question is missing below is the missing part
when H₂O and H₂O₂ is added to Mn(OH)₂(s) and put in water bath to dissolve
answer : attached below
Explanation:
When Mn²⁺ ions are separated from the mixture, attached below are the requires reaction equations that shows the process of separation.
Mn²⁺ ions are separated to the right of the reaction equations
A knife is a example of a pulley True or false
Answer:
In my Opinion
Explanation:
False. There's no pulley system or activity in a knife.
A student weighs out a 6.04 g sample of , transfers it to a 100. mL volumetric flask, adds enough water to dissolve it and then adds water to the 100. mL tick mark. What is the molarity of chromium(III) sulfate in the resulting solution
Answer:
"0.1540 M" is the correct answer.
Explanation:
The given values are:
Mass of sample,
M = 6.04 g
Volume,
V = 100 mL
or,
= 100×10⁻³ L
Molar weight of Chromium(III) sulfate
MW = 392.16 g/mol
Now,
The molarity will be:
= [tex]\frac{M}{MW\times V}[/tex]
By putting the values, we get
= [tex]\frac{6.04}{392.16\times 100\times 10^{-3}}[/tex]
= [tex]\frac{6.04}{39.216}[/tex]
= [tex]0.1540 \ M[/tex]
CaBr + KOH – Ca(OH), + KBr (balance first) What mass, in grams, of
CaBr is consumed when 48.00 g of Ca(OH), is produced?
please help asap
Answer:
129.73 g of CaBr₂
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
CaBr₂ + 2KOH –> Ca(OH)₂ + 2KBr
Next, we shall determine the mass of CaBr₂ that reacted and the mass of Ca(OH)₂ produced from the balanced equation. This can be obtained as follow:
Molar mass of CaBr₂ = 40 + (80×2)
= 40 + 160
= 200 g/mol
Mass of CaBr₂ from the balanced equation = 1 × 200 = 200 g
Molar mass of Ca(OH)₂ = 40 + 2(16 + 1)
= 40 + 2(17)
= 40 + 34
= 74 g/mol
Mass of Ca(OH)₂ from the balanced equation = 1 × 74 = 74 g
SUMMARY :
From the balanced equation above,
200 g of CaBr₂ reacted to produce 74 g of Ca(OH)₂.
Finally, we shall determine the mass of CaBr₂ that react when 48 g of Ca(OH)₂ were produced. This can be obtained as follow:
From the balanced equation above,
200 g of CaBr₂ reacted to produce 74 g of Ca(OH)₂.
Therefore, Xg of CaBr₂ will react to produce 48 g of Ca(OH)₂ i.e
Xg of CaBr₂ = (200 × 48)/74
Xg of CaBr₂ = 129.73 g
Thus, 129.73 g of CaBr₂ were consumed.
A solution was prepared by dissolving 27.1g of sucrose (C12H22O11) in 250 g of water. Find the molality of the solution(molar mass of C12H22O11 is 342.8)
-.108 m
-108 m
-317 m
-.317 m
Answer:
M = 0.317 m
Explanation:
From the given information:
Using the following formula:, the molality M is:
[tex]M= \dfrac{W_A}{M_A}\times \dfrac{1000}{W_B(g)}[/tex]
where;
M = molality
[tex]W_A[/tex]= mass of the solute = 27.1 g
[tex]M_A[/tex] = molar mass of the solute = 342.8
[tex]W_B[/tex] = mass of the given solvent = 250 g
∴
[tex]M= \dfrac{W_A}{M_A}\times \dfrac{1000}{W_B(g)}[/tex]
[tex]M= \dfrac{27.1}{342.8}\times \dfrac{1000}{250}[/tex]
M = 0.317 m
what mass of carbon dioxide will be produced when 12.9 g of butane reacts with an excess of oxygen in the following reaction?
How do atoms combine to form all of the diverse types of matter in our universe?
Pls, Help with a good valid answer and explanation. will mark brainliest.
Answer:
Using electrons.
Explanation:
The properties of matter depend on the types of atoms that matter is made of. Matter can exist in two forms. It can be a pure substance. (ck12.org)
Atoms combine, or bond, using their electrons. When atoms from two or more different elements bond, they form a compound. (resources.finalsite.net) Atoms form chemical bonds with other atoms when there's an electrostatic attraction between them. This attraction results from the properties and characteristics of the atoms' outermost electrons, which are known as valence electrons. (wonderpolis.org)
Something like this??
Determine the chemical formula for the molecule shown.
-Which of the following terms could most likely apply to the molecule shown?
hydrocarbon
polymer
organic
inorganic
Explain your answer to the second part of the question above.
Answer: Formula is C4H8O. In every branch of line formula there are Carbon atom. Carbon makes 4 bonds so In branch left in which two CH3-groups are attached there are also an Hydrogen aton which is not shown.
Explanation: Molecule is organic, it is classified as aldehyde.
Hydrocarbons contains only Carbon and Hydrogen atoms, Organic molecules can contain also other atoms.
Reactions of aldehydes are reduction to alcoholes or oxidation to carboxylic acids. It can not for a polymer.
H2CO3 - H2O + CO2
Need as soon as possible
Answer:
H2CO3 --> H2O + CO2
Explanation:
H = 2
C = 1
O = 3
________
H = 2
C = 1
O = 1 +2 = 3
Solve (2 x 10^3) + (7 x 10^5) *
Answer:
702000
Explanation:
(2 x 10^3) + (7 x 10^5)
=> 2 x 1000 + 7 x 100000
=> 2000 + 700000
=> 702000
15. Objects can have kinetic energy, potential energy, or both. Energy can be in the form of motion. Energy can
also be stored by objects in various ways, including position, chemical bonds, or physical state.
Which statement is true? And why?
a. An object’s mass has no effect on its potential energy.
b. Potential energy is converted to kinetic energy as a stationary object begins to move.
c. Kinetic energy is converted to potential energy as a stationary object begins to move.
d. A stretched rubber band stores no energy.
Answer: b because Potential energy is converted to kinetic energy as a stationary object begins to move.
Explanation:
_HCN+_CUSO4=_CUSO4+_CU(CN)2
