Answers
Answer:
See explanation
Explanation:
pOH = -log[OH^-]
pOH =-log[1×10^-4 molL-1]
pOH = 4
pH +pOH =14
pH = 14 -4
pH =11
b) pOH = -log[OH^-]
pOH =-log[4.9×10^-2molL-1]
pOH = 1.31
pH +pOH =14
pH = 14 -1.31
pH =12.69
c)
pH= -log[H^+]
[H^+] = Antilog [-pH]
[H^+] = Antilog [-3]
[H^+] = 1 × 10^-3 molL-1
d) pOH = -log[OH^-]
[OH^-] = Antilog[-pOH]
[OH^-] = Antilog[-10.4]
[OH^-] = 3.98 ×10^-11
[OH^-] [H^+] = 1 × 10^-14
[H^+] = 1 × 10^-14/3.98 ×10^-11
[H^+] =2.5 ×10^-4 MolL^-1
e) A solution of pH 9 is basic because the pH scale is calibrated in such as way that 0-6.9 is acidic, 7 is neutral and 8 - 14 is basic.
f)
[H^+] = number of moles/volume
[H^+] = 0.35 moles/8L
[H^+] = 0.044 MolL^-1
pH = - log [H^+]
pH = -log [0.044 MolL^-1]
pH= 1.36
Related Questions
please help me thank u !
Answers
How does a nuclear reactor produce electricity
Answers
Answer:
Explanation:
Nuclear reactors are the heart of a nuclear power plant. They contain and control nuclear chain reactions that produce heat through a physical process called fission. That heat is used to make steam that spins a turbine to create electricity. Nuclear power plants use heat produced during nuclear fission to heat water. The heat produced during nuclear fission in the reactor core is used to boil water into steam, which turns the blades of a steam turbine. As the turbine blades turn, they drive generators that make electricity
What is the percentage composition of each element in ammonia, NH3?
82.35% N; 17.65% H
80.55% N; 19.45% H
79.46% N; 20.54% H
78.57% N; 21.43% H
Answers
The answer is A
Taking into account the molar mass of each elemente and ammonia, the correct answer is the first option: the percentage composition of each element in ammonia, NH₃ is 82.35% N; 17.65% H
First of all, molar mass is the mass of one mole of a substance, which can be an element or a compound. In the case of a compound, it is calculated by adding the atomic masses of the atoms that make up the molecule.
In this case, being the atomic mass of N equal to 14 and the atomic mass of H equal to 1, the molar mass of NH₃ is calculated as:
NH₃= 14 + 3* 1= 17
Now, to obtain the percentage composition of each element, you must divide each individual atom with the mass of ammonia and multiply by 100 to obtain the percentage:
N: [tex]\frac{14}{17} x100[/tex]
H: [tex]\frac{1x3}{17} x100[/tex] In this case, the atomic mass of hydrogen H is multiplied by 3 because 3 hydrogens are present in ammonia.
Solving:
N: [tex]\frac{14}{17} x100[/tex]= 0.8235×100= 82.35 %
H: [tex]\frac{3}{17} x100[/tex]= 0.1765×100= 17.65 %
Finally, the correct answer is the first option: the percentage composition of each element in ammonia, NH₃ is 82.35% N; 17.65% H
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Please somone help me with a chemistry question brainliest to whoever answers correctly and 20 points
Answers
Answer:
3132 is the answer
Explanation:
3BaCl2 + Al2S3 → 3BaS + 2AlCl3
Answer:
Explanation:
Hope this helps u !!
help bc i need it lol
Answers
Answer:
2 XE + 1 AB. --> 1 AE2 + 2 XB
Above equation is now balanced
Jello has a density of 1.14 g/mL. A box of Jello makes 475 mL of Jello and has 13 g of sugar. Determine the % m/m of sugar in the Jello. (Hint: d=m/v)
Answers
Answer:
2.34 %
Explanation:
Since the density of the Jello, ρ = 1.14 g/mL and ρ = m/v where m = mass of jello and v = volume of jello = 475 mL.
So, m = ρv
substituting the values of the variables into the equation, we have
m = ρv
m = 1.14 g/mL × 475 mL = 541.5 g
Since we have 13 g of sugar in the jello, the total mass present is 13 g + 541.5 g = 554.5 g
So, the percentage by mass of sugar present % m/m = mass of sugar present/total mass × 100 %
= 13 g/554.5 g × 100 %
= 0.0234 × 100 %
= 2.34 %
So, the percentage by mass of sugar present % m/m = 2.34 %
What makes plants the beginning of the food chain?
please answer my question aswell as my last one!
Answers
Answer: A
Explanation:
i just took the quiz and it was right!
If you could somehow travel inside an atom and look around, what part of the atom would you want to look at? What would you want to understand better as a result of your "travels"? Write your answers in 2-3 paragraphs.
Answers
Answer:
See explanation
Explanation:
The interior of the atom is composed of electrons which move around in orbits and the nucleus. The nucleus contains protons and neutrons. The electrons are negatively charged while the protons are positively charged, the neutrons have no charge at all.
The atom is held together by electrostatic interaction between the electrons and protons in the nucleus. The protons and neutrons account for most of the mass of the atom.
The greatest wonder that I will like to really understand in the interior of the atom is the nature of the interaction between the neutrons and protons in the atomic nucleus which holds the nucleons together. The neutrons have no charge while the protons are positively charged. What sort of interaction could exist between an uncharged particle and a charged particle? That is what I will like to understand better as a result of my travels into the interior of the atom.
Answer:
help
Explanation:
An unknown substance weighing 42.0 g was heated from 36.0°C to 65.0°C. In this process, the
substance absorbed 5895 J of energy. What is the specific heat of the substance?
A. 5895 J/(g*C)
B. 4.18 J/(g*C)
C. 4.84 J/( g*C)
D. O.06 J/(g*C)
Answers
Answer:
A. 5895 J/g*C)
Explanation:
An unknown substance weighing 42.0 g was heated from 36.0°C to 65.0°C. In this process, the substance absorbed 5895 J of energy.
A student is provided with a sample of iron pyrite and a sample of gold. Suggest how the student could distinguish between the two substances
Answers
Answer:
Gold and pyrite both have a brilliant metallic luster, but are different tones of yellow. Gold is golden to silvery yellow, whereas pyrite is a pale to medium brassy yellow that sometimes tarnishes.
Explanation:
What process takes place when hydrogen-3 and hydrogen-2 combine to form
helium-4 plus a neutron?
A. Fusion
B. Alpha decay
C. Beta decay
D. Fission
Answers
Answer:
A. Fusion
Explanation:
Which of the following is the strongest acid?
a.pH = 12
b.pOH = 5
c.[H+] = 1 x 10-8
d.pOH = 12
Answers
Answer:
d. pOH = 12 => pH = 14 - 10 = 2 => most acidic
Explanation:
pH = -log[H⁺] => [H⁺] = 10^-pH
By definition, if ...
[H⁺] > 10⁻⁷ > [OH⁻] => pH < -log(10⁻⁷) < 7 => pOH > 14 - 7 > 7 => acidic solution
[H⁺] = 10⁻⁷ = [OH⁻] => pH = -log(10⁻⁷) = 7 => pOH = 14 - 7 = 7 => neutral solution
[H⁺] < 10⁻⁷ < [OH⁻] => pH > -log(10⁻⁷) > 7 => pOH < 14 - 7 < 7 => basic solution
∴ From most basic to most acidic ...
a. pH = 12 => most basic
b. pOH = 5 => pH = 14 - 5 = 9
c. [H⁺] = 1 x 10⁻⁸ => pH = -log(10⁻⁸) = -(-8) = 8
d. pOH = 12 => pH = 14 - 10 = 2 => most acidic
How many moles in 4.65 g of Helium?
Answers
Answer:
4.65 g x 1 mol/4.0026 g/mol = 1.162 mol helium
Explanation:
What is the limiting reactant in a reaction where 10.0 mol of iron is treated with 12.0 mol of bromine? The product that forms is FeBr3. First, write and balance the chemical equation. Next, calculate the moles of FeBr3 that can be made from 10.0 mol of Fe. Then calculate the moles of FeBr3 that can be made from 12.0 mol of bromine. The smaller amount of FeBr3 reveals the limiting reactant.
Answers
Answer: The limiting reagent in the reaction is bromine.
Explanation:
Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.
Excess reagent is defined as the reagent which is left behind after the completion of the reaction.
Given values:
Moles of iron = 10.0 moles
Moles of bromine = 12.0 moles
The chemical equation for the reaction of iron and bromine follows:
[tex]2Fe+3Br_2\rightarrow 2FeBr_3[/tex]
By the stoichiometry of the reaction:
If 3 moles of bromine reacts with 2 moles of iron
So, 12.0 moles of bromine will react with = [tex]\frac{2}{3}\times 12.0=8moles[/tex] of iron
As the given amount of iron is more than the required amount. Thus, it is present in excess and is considered as an excess reagent.
Hence, bromine is considered a limiting reagent because it limits the formation of the product.
Thus, the limiting reagent in the reaction is bromine.
Which is a characteristic of nuclear fission?
Answers
Answer:
Contrasting Nuclear Fission and Nuclear Fusion
Nuclear FissionByproducts of the reaction: Fission produces many highly radioactive particles.Conditions: Critical mass of the substance and high-speed neutrons are required.Energy Requirement: Takes little energy to split two atoms in a fission Explanation:
Scenario 1: Sarah, your lab partner, accidentally poured too much
sodium chloride (chemical) into a beaker. She wants to pour the rest back
into the original container. What should you do? Explain
Scenario 2: You notice that yout lab partner is chewing gum and using a
beaker as a cup to get water. He then takes a drink from the beaker. He
assures you that it is clean and you don't have to worry. Why is this
dangerous in lab? Explain.
Scenario 3: In lab, you are working with an open flame (a birthday
candle) and your friend calls you over to see new background picture on
his chromebook. What should you do? Explain
Answers
Scenario 2: chemicals have been on beakers and they should not be drank out of, your partner should also not be eating or drinking in the lab.
Scenario 3: you should never walk away from an open flame
How many joules are required to heat 120.5!grams of water from 5.6°C to 62.5°C
Answers
Answer:
The amount of energy required is 17 kJ.
Explanation:
Angiosperms produce brightly colored blooms and sweet-smelling flowers. Why have angiosperms developed these adaptations? A. to ensure seed dispersal B. to keep predators from eating the plants C. to attract pollinators and help ensure fertilization D. to allow time for seed development
Answers
Answer:
C
Explanation:
Angiosperms have developed these adaptations because it attracts pollinators which helps the ecosystem grow.
Potassium (K):
g/mol?
Answers
On a warm sunny day, a deer is searching something to drink. The deer is most likely responding to which kind of stimulus?
Answers
Answer:
External stimulus of thirst
Answer:
your answer is: the external stimulus of thirst
Explanation:
I took the test :)) hope this helps!!!!!!
The solubility of gases in liquids The solubility of gases in liquids increases as temperature increases and increases as pressure increases. increases as temperature increases and decreases as pressure increases. decreases as temperature increases and decreases as pressure increases. decreases as temperature increases and increases as pressure increases. is independent of temperature and increases as pressure increases.
Answers
Answer:
As the kinetic energy of the gaseous solute increases, its molecules have a greater tendency to escape the attraction of the solvent molecules and return to the gas phase. Therefore, the solubility of a gas decreases as the temperature increases.
Explanation:
As the kinetic energy of the gaseous solute increases, its molecules have a greater tendency to escape the attraction of the solvent molecules and return to the gas phase. Therefore, the solubility of a gas decreases as the temperature increases
Hydrogen and nitrogen react to form ammonia. The chemical equation for this reaction is shown here. 3 H2(g) + N2(g) 2 NH3(g). What amount of hydrogen will produce 44.0 mol of ammonia?
66.0 mol
88.0 mol
132.0 mol
29.3 mol
Answers
Answer:
someone already answered but i think it's 132.0 mol too
A gas has a volume of 1000.0 mL at a temperature of 20.OK and a pressure
of 1.0 atm. What will be the new volume when the temperature is changed
to 40.0K and the pressure is changed to
0.5 atm?
Answers
Answer:
4000mL
Explanation:
Using the combined gas law equation as follows:
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (atm)
P2 = final pressure (atm)
V1 = initial volume (mL)
V2 = final volume (mL)
T1 = initial temperature (K)
T2 = final temperature (K)
According to the information given in this question:
V1 = 1000mL
T1 = 20K
P1 = 1.0atm
V2 = ?
P2 = 0.5atm
T2 = 40K
Using P1V1/T1 = P2V2/T2
1 × 1000/20 = 0.5 × V2/40
1000/20 = 0.5V2/40
50 = 0.5V2/40
50 × 40 = 0.5V2
2000 = 0.5V2
V2 = 2000/0.5
V2 = 4000mL
Adding a catalyst to a system at equilibrium lowers the activation energy required by a system, which system, which shifts the equilibrium position toward the products.
True or false?
Answers
Answer: False
Explanation: Took the test
Answer:
False
Explanation:
One way industrial chemists aim to improve manufacturing and sales is by manipulating extemal factors to increase the rate of the reaction.
As an industrial chemist you have been asked by the CEO of your company to propose conditions that will increase the rate of production of
acetaminophen (the active ingredient in Tylenols). In a well-written letter to the CEO include three possible methods for increasing the
reaction rate and explain why each proposed change will increase the reaction rate Justity your recommendations using scientinc principles
The chemical synthesis of acetaminophen C.H.NO, is represented by the following equation
Answers
There are several methods that can be employed to increase yield in the chemical synthesis of acetaminophen.
What is chemical synthesis?The term chemical synthesis has to do with the method of producing a chemical substance from other chemical substances.
It is usual in industrial chemistry to seek to optimize the yield of the target product. In the chemical synthesis of acetaminophen as shown in the image attached, the yield of the product can be increased by;
1) Removal of the ethanoic acid byproduct to drive the forward reaction
2) Increasing the concentration of each of the reactants to ensure that more product is obtained.
3) Operating the process at a higher temperature to ensure that reaction is more efficient.
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Can you identify what object is being represented by the model on the right? A. Arc of a circle B. Amount of radiation C. Area of a circle
Answers
Answer:
C area of a Circle.
Explanation:
Got it right. Edg2021.
Answer:
C
) area of a circle
Explanation:
edge 2023
Which is the most likely way an automotive engineer would use chemistry?
A. By testing the maximum speed and stopping distance of a new
car
B. By doing market research to determine which types of cars
consumers want
C. By designing cars that are more aerodynamic
D. By making parts that reduce the pollutants cars emit
Answers
Answer:
by making parts... emit
I need to know the answer to this question
Answers
Answer:
your awnser would be 72.1
Explanation:
hope this helps have a good day :]
Perform the following
mathematical operation, and
report the answer to the correct number of significant figures.
7.68 x 4.564 = [?]
Answers
Witch part of an atom is mostly empty space?