Answer: [tex]1.94\times 10^{-3}g[/tex] of NaOH
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
Putting in the values:
[tex]10.020=-\log[H^+][/tex]
[tex][H^+]=9.55\times 10^{-11}[/tex]
[tex][H^+][OH^-]=10^{-14}[/tex]
[tex][OH^-]=\frac{10^{-14}}{9.55\times 10^{-11}}=1.05\times 10^{-4}M[/tex]
[tex]NaOH\rightarrow Na^++OH^-[/tex]
[tex]Molarity=\frac{moles\times 1000}{\text {Volume in ml}}[/tex]
[tex]1.05\times 10^{-4}M=\frac{moles\times 1000}{463ml}[/tex]
moles = [tex]4.86\times 10^{-5}[/tex]
Mass of [tex]NaOH=moles\times {\text {Molar mass}}=4.86\times 10^{-5}\times 40=1.94\times 10^{-3}g[/tex]
Thus [tex]1.94\times 10^{-3}g[/tex] of NaOH is needed to prepare 463 mL of solution with a pH of 10.020
An exothermic reaction releases 13,450J of heat. How many calories of energy are released? A) 5 56,274 calories B)1,244 caloriesC) 134,500 caloriesD) 3,215 calories
Answer:
The correct option is;
D) 3,215 calories
Explanation:
Here we are required to convert 13,450 J to calories
1 calorie is the amount of heat required to raise the temperature of 1 gram of water by 1°C
Therefore, 1 calorie = 4.184 Joules
Hence, 1 Joule = 1/4.184 calorie for which we have;
13,450 J = 13,450 × 1/4.184 calories = 13,450/4.184 calorie
13,450 J = 3,214.63 calories
Rounding up to the nearest whole number, we have;
13,450 J ≈ 3,215 calories.
Which of the following statements is true?
Sound vibrations are changed into electrical impulses by the eardrum.
It is dangerous to listen to sounds over 160 dBs.
High-pitched sounds have low frequencies.
All of the above.
Answer:
all of the above!! :)))
Explanation:
a. What is the mass in grams of 4.2 mols of FeO2?
According to mole concept, there are 368.928 g mass in 4.2 moles of FeO₂.
What is a mole?Mole is defined as the unit of amount of substance . It is the quantity measure of amount of substance of how many elementary particles are present in a given substance.
It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on the type of substance. Amount of elementary entities in a mole is called as Avogadro's number.
It is widely used in chemistry as a suitable way for expressing amounts of reactants and products.For the practical purposes, mass of one mole of compound in grams is approximately equal to mass of one molecule of compound measured in Daltons. Molar mass has units of gram per mole . In case of molecules, where molar mass in grams present in one mole of atoms is its atomic mass.
Number of moles=mass/molar mass
Thus, mass=4.2×87.84=368.928 g.
Thus, there are 368.928 g mass in 4.2 moles of FeO₂.
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If a gas occupies 22.4 L at 0.265 atm, then what will the pressure be in atmospheres if the gas occupies 35.52 L? Assume all other
variables are held constant
A)0.167 atm
B)0.437 atm
C)0.886 atm
D)149 atm
Answer:
The new pressure is 0.167 atm
The correct answer is option A
Explanation:
Step 1: Data given
Volume of the gas = 22.4 L
Pressure of the gas = 0.265 atm
The volume increases to 35.52 L
Step 2: Calculate the new pressure
P1*V1 = P2*V2
⇒with P1 = the initial pressure = 0.265 atm
⇒with V1 = the initial volume = 22.4 L
⇒with P2 = the new pressure = TO BE DETERMINED
⇒with V2 = the increased volume = 35.52 L
0.265 atm * 22.4 L = P2 * 35.52 L
P2 = (0.265 atm * 22.4 L) / 35.52 L
P2 = 0.167 atm
The new pressure is 0.167 atm
The correct answer is option A
After constructing the circuit, Aliyah and Jeremy noticed that the light bulb stays on all the time. This means the batteries will get used up when the flashlight does not need to be on. What is something Aliyah and Jeremy can do to solve this problem?
Answer: Implement a switch
Explanation:
This forms a circuit break or way to easily turn the flow of electricity on or off.
EMERGENCY: I WILL FAIL: PLS HELP WILL MARK BRAINLIEST JUST PLS HELP
Answer:
condensation: moisture builds up on window; dew forms on blades of grass
deposition: snow is made inside a cloud; frst froms on window?
Explanation:
How many copper atoms are in 70 grams of copper
Using the diagram of the forces on an airplane, which arrow represents the force of gravity?
A) A
B) B
C) C
D) D
Answer:
Is there a diagram that you can post
Answer:
D
Explanation:
Usatestprep :)
PLEASE HELP I WILL GIVE BRAINLEST! what is life about?
Answer:
To live for God.
Explanation:
We are Gods creation. We are here to live for the Lord, to do love& to help save each other so when time comes we will be forever blessed.
Answer:
life is about life I think
The theoretical yield is the amount of product actually produced.
a. True
b. False
Answer:
a. True
Explanation:
Theoretical yield is the amount of product that could be obtained if a chemical reaction has 100% efficiency.
Hope it helps...
In the reaction N2 + 3H2 - 2NH3, how many
grams of H, are needed to produce exactly I mole
of ammonia?
A. lg
B. 2g
C.3g
D.4g
Answer:
B. 2g
Explanation:
So first you have to find the mole to mole ratio then convert it to grams if that makes sense. So the mole to mole ratio is 2 ammonia to 3 hydrogen gas. So then after you do that conversion you can solve for grams then. Sorry I am not that great at explaining.
How do you convert kilometers to grams
By multiplying the mass value by 1000.
Answer:
Hey!
What you have to do is to multiply the amount of mass * i.e. 67.9g * by 1000 * 67,900kg! *
Explanation:
HOPE THIS HELPS!
A chemist needs 2.00 liters of hydrochloric acid. How many pints is this?
Answer:
4.22675
Explanation:
Describe the interactions with the Sun, Earth and Moon system that result in Lunar Cycle / Phases.
Answer: The tides are another interaction in the sun-earth-moon system. The tides happen because the moon and sun pull on the oceans, causing them to rise and fall each day. The moon has a bigger effect than the sun because it is closer. The angle of the sun as the earth orbits over the course of a year causes the seasons.
Explanation:
Which is a property of every heterogeneous mixture?
The mixture is made up of at least two different states.
The mixture is made up of something dissolved in a liquid.
The composition of the mixture is the same throughout.
The characteristics of the mixture change within a sample.
Answer:
D.) The characteristics of the mixture change within a sample
Explanation:
Because the guy above me is wrong
Answer:
D.) The characteristics of the mixture change within a sample.
Explanation:
HTH!! Have a good day!!! Don't forget to smile!!!!
I need the correct answer
Answer:
d.
Explanation:
They can be spread through contaminated surfaces.
Answer:
d
Explanation: pathogens csnnot be spread be sontaminated surfesec
Which of the following is most likely a homogeneous mixture?
O A. A tossed vegetable salad
B. Chunky peanut butter
O C. Chocolate chip cookies
OD. A vanilla milkshake
Answer:
D)A vanilla milkshake
Explanation:
Relate dark matter to the development of the universe after the Big Bang. In 3-5 sentences, speculate on how the development of the universe would have been different if there had been no dark matter. In your answer, use the term structures.
Please answer if you do i will mark you as brainliest
Answer:
Without dark matter galaxies would loose an extreme amount of gas required to create stars.
Without dark matter the universe wont have as many galaxies clumped together forming larger versions of those galaxies. This would cause a change in the structure of the "skeleton" of the web.
(Hope this can help, I didn't do exactly as it is said to because that is your job)
:)
Explanation:
Forbes gives somewhat of an explanation if you are curious.
(Ethan Siegal, "The Universe Would Be Very Different Without Dark Matter", Forbes)
Dark matter makes up most of matter in the universe and is found by a quarter of the total composition of the space. After the event of the big bang, the universe expanded and dark matter grew.
Dark matter accounts for about 85% of the matter in the universe. Its presence can be felt in the gravitational effects. Dark matter doesn't interact with the electromagnetic field. After the big bang event, the dark matter still can be found in larger galaxies and contest about 26% of mass-energy and 69% of dark energy. If there had been no dark matter there would be no structure of the cosmic web of galaxies. That is there would be no connection between the galaxies and would remain in isolated fragments.Thus dark matter is a link within and with the comic web.
Learn more about the dark matter and its development-related after the big bang event
brainly.com/question/16725768.
Why do the atoms in a molecule want to be so far apart? (Mention Electron domains/Electrons)
Answer:
Because like chargee repel, two molecules will resist being brought close together.
Explanation:
The shorter the distance is between them, the more energy it takes to push them to get even closer. If the molecules approach each other with sufficient energy, however, they may exchange atoms or even form a bond( chemical reaction)
An exothermic reaction releases 13,450J of heat. How many calories of energy are released? A) 5 56,274 calories B)1,244 caloriesC) 134,500 caloriesD) 3,215 calories
Answer:
The correct option is;
D) 3,215 calories
Explanation:
Here we are to convert the units of energy
The given units is in Joules, J, while the required units is in calories, where the calorie is defined as the amount of heat required to raise the temperature of 1 gram of water by 1°C
The conversion formula therefore is 1 calorie = 4.1868 J
Hence, 1 J = 1/4.1868 calories
13,450 J = 13,450 × 1/4.1868 calories = 13,450 /4.1868 calories = 3212.477 calories
∴ 13,450 J ≈ 3,215 calories.
What is a conductor
When electrons move easily though objects
When electrons cannot move easily through objects
When electrons are at rest
Select the correct answer.
Which statement best describes the image?
A.
Ocean temperatures are relatively stable. During the day, the ocean cools the hotter air temperatures above land.
B.
Ocean temperatures are relatively stable. During the night, the ocean heats the cooler air temperatures above land.
C.
Ocean temperatures experience high fluctuations. During the day, the land cools the hotter air temperatures above the ocean.
D.
Ocean temperatures experience high fluctuations. During the night, the land heats the cooler air temperatures above the ocean.
Answer:
C.
Ocean temperatures experience high fluctuations. During the day, the land cools the hotter air temperatures above the ocean.
Explanation:
Generally ocean temperatures range from about -2o to 30o C (28-86o F). The warmest water tends to be surface water in low latitude regions, while the surface water at the poles is obviously much colder
C. Ocean temperatures experience high fluctuations. During the day, the land cools the hotter air temperatures above the ocean.
What is the hottest ocean temperature?The hottest ocean area is in the Persian Gulf, where water temperatures at the surface exceed 90 degrees Fahrenheit in the summer. Another hot area exists in the Red Sea, where a temperature of 132.8 degrees Fahrenheit has been recorded at a depth of about 6,500 feet.
What is a good temperature to swim in the ocean?A little cooler than your body temperature (98.6° Fahrenheit) should not be too cold so that you don't get chilled. 70° to 78° Fahrenheit is the range where most folks feel "comfortable" swimming.
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60.0 g of NH Cl are dissolved in 100 grams of water at 60.0° C. This solution is
A
supersaturated
B
saturated
С
unsaturated
D
none of the above
Answer:
B) is the correct answer
pls help Photosynthesis is used to produce food for plants in the form of glucose. In the process, oxygen is released. As shown in the diagram, plants require water and carbon dioxide (from the air). What else is required for photosynthesis and what role does it play? A) Light is required to provide energy for photosynthesis. B) ATP is required as an energy source for photosynthesis. C) Glucose is required as an energy source for photosynthesis D) Oxygen is required to split water molecules in photosynthesis.
Answer:
A) light is required
Explanation:
ATP, Glucose, and oxygen are created from the process
What is the oxidation state of Fe(s)
The oxidation state is zero for Fe (s)
which is correct? not sure which is right
Answer:
butane
Explanation:
The _____ of a weak acid is strong.
a. conjugate acid
b. conjugate base
c. acid
d. base
Answer: conjugate base
Explanation:
According to the Bronsted-Lowry conjugate acid-base theory, an acid is defined as a substance which looses donates protons and thus forming conjugate base and a base is defined as a substance which accepts protons and thus forming conjugate acid.
A weak acid has a strong conjugate base whereas a strong acid has a weak conjugate base. Similarly a weak base has a strong conjugate acid whereas a strong base has a weak conjugate acid.
[tex]CH_3COOH+NH_3\rightarrow CH_3COO^-+NH_4^+[/tex]
Acetic acid [tex]CH_3COOH[/tex] is weak acid which has strong conjugate base [tex]CH_3COO^-[/tex]
Need help with these three pls!!
Answer:
True True False
Explanation:
Valves are in most veins (to prevent backflow). Also valves in the chart and an in an combustion engine.
So the first statement is True.
Valves control the flow rate and direction of fluid within a closed system. So the second statement is True.
1 Pa = 1 N/m² So since 1 Pa equals to one newton per square metre the third statement is False.
if the volume and Kelvin temperature are reduced by one-half what will happen to the pressure???
Answer:
the pressure will decrease
Explanation:
Ideal gas law is valid only for ideal gas not for vanderwaal gas. The pressure will remain same as the initial pressure on decreasing volume and temperature by half.
What is ideal gas equation?Ideal gas equation is the mathematical expression that relates pressure volume and temperature. real gas can become ideal gas at low pressure and high temperature.
Mathematically the relation between Pressure, volume and temperature can be given as
PV=nRT
where,
P = pressure of gas
V= volume of gas =1/2V
n =number of moles of gas
T =temperature of gas =T/2
R = Gas constant = 0.0821 L.atm/K.mol
Substituting all the given values we get
P×(V/2)=nR(T/2)
(PV)/2=(nRT)/2
PV=nRT
Therefore, the pressure will remain same as the initial pressure on decreasing volume and temperature by half.
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Which of these defines a volcano?
A. An undersea rift that can cause the ocean floor to move
B. A mountain on Earth's crust through which molten material leaves the mantle
C. A large pile of rocks and other debris that turn into liquid when heated
D. An extremely tall collection of liquid metals that harden when cooled
Answer:
B
Explanation:
