Answers
Answer:
2. A
3.B
4.B
Hope this helps,Pls mark as Brainliest!!
Related Questions
a. What is the mass in grams of 4.2 mols of FeO2?
Answers
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.
Learn more about moles,here:
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How does the pressure of a container change as the volume is changed?
Answers
Answer: If the volume is decreased, the pressure would increase because the gas molecules have less space to move around. Same goes for the opposite; if the volume increased, the pressure would decrease because the molecules have more space to move and aren't packed as tightly .
Hope this helps!!!
The mole concept will most likely be used in
calculating the average height of a mountain range.
measuring how many liters of gasoline are poured into a tank.
determining how many ozone molecules are lost in the atmosphere.
finding the mass of a piece of steak in a butcher shop.
Answers
Answer:
determining how many ozone molecules are lost in the atmosphere
Pls Mark as Brainliest!!! if this helps...
The mole concept The mole concept can be used to determine the number of ozone molecules are lost in the atmosphere.
The mole concept was introduced by Avogadro. The mole is the SI unit of amount of substance. According to Avogadro, one mole of a substance contains 6.02 × 10^23 atoms, ions, molecules etc.
The mole concept is important in many chemical calculations. The mole concept can be used to determine the number of ozone molecules are lost in the atmosphere. (option C)
Learn more: https://brainly.com/question/7287712
How does activation energy affect the progress of a reaction?
O A. The reaction will not occur unless the activation energy is met.
B. The activation energy decreases the energy needed for a reaction
to progress.
C. The activation energy increases how quickly the reaction will
progress.
D. The activation energy determines equilibrium concentrations of
products.
Answers
Answer:
The reaction will not occur unless the activation energy is met.
Explanation
Answer:
A. The reaction will not occur unless the activation energy is met.
Explanation:
a.p.e.x
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.
Answers
Answer:
all of the above!! :)))
Explanation:
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
Answers
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
0.450 moles of K2SO4 are dissolved in 195.0 mL of water. Calculate the molarity of the solution.
Answers
Answer:
2.31M
Explanation:
The following data were obtained from the question:
Mole of K2SO4 = 0.450 mole
Volume of water = 195.0 mL = 195/1000 = 0.195L
Molarity =...?
Molarity is defined as the mole of solute per unit litre of the solution. This can be expressed as:
Molarity = mole /Volume
With the above formula we can calculate the molarity of the K2SO4 solution as follow:
Molarity = mole /Volume
Molarity = 0.450/0.195
Molarity = 2.31M
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
Answers
Answer:
D)A vanilla milkshake
Explanation:
That’s the case because you can’t physically separate the different posts that make up the mixture.
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.
Answers
Answer:
A) light is required
Explanation:
ATP, Glucose, and oxygen are created from the process
Inside the retina of our eyes are receptors called rods and cones. Rods measure the brightness we see and cones determine _____.
A) the color we see
B) the white we see
C) the dimness we see
D) the loudness we hear
Answers
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?
Answers
Answer: Implement a switch
Explanation:
This forms a circuit break or way to easily turn the flow of electricity on or off.
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
Answers
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.
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
Answers
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.
If the mole fraction of sulfuric acid H2SO4 is 0.432 what is the percent by mass of H2SO4.
Answers
Answer:
19.47%
Explanation:
The percentage by mass of [tex]H_2SO_4[/tex] would be 19.47%.
The percentage by mass of a substance in solution is calculated as:
[tex]\frac{mass of substance}{mass of substance + water} * 100%[/tex]
Given that the mole fraction of [tex]H_2SO_4[/tex] = 0.432
The total number of mole fraction of a solution = 1
Hence, mole fraction of water = 1 - 0.432 = 0.568
Mass of water = molar mass x mole
= 98.079 x 0.432 = 42.37 g
Mass of [tex]H_2SO_4[/tex] = molar mass x mole
= 18.02 x 0.568 = 10.24 g
Hence,
%mass of [tex]H_2SO_4[/tex] = [tex]\frac{10.24}{10.24 + 42.37} * 100[/tex]
= 19.47%
A chemist needs 2.00 liters of hydrochloric acid. How many pints is this?
Answers
Answer:
4.22675
Explanation:
How do you convert kilometers to grams
Answers
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!
If a buffer has an initial pH of 6.34 and the acid has a Ka of 3.46 × 10-4, what is the ratio of conjugate base to weak acid in the buffer system?
Answers
Answer: The ratio of conjugate base to weak acid in the buffer system is 758 : 1
Explanation:
The dissociation constant for acid = [tex]K_a=3.46\times 10^{-4}[/tex]
pH = 6.34
First we have to calculate the value of [tex]pK_a[/tex].
The expression used for the calculation of [tex]pK_a[/tex] is,
[tex]pK_a=-\log (K_a)[/tex]
Now put the value of [tex]K_a[/tex] in this expression, we get:
[tex]pK_a=-\log (3.46\times 10^{-4})[/tex]
[tex]pK_a=3.46[/tex]
Now we have to calculate the ratio of conjugate base to weak acid in the buffer system
Using Henderson Hesselbach equation :
[tex]pH=pK_a+\log \frac{[\text {conjugate base}]}{[Acid]}[/tex]
Now put all the given values in this expression, we get:
[tex]6.34=3.46+\log \frac{[\text {conjugate base}]}{[Acid]}[/tex]
[tex]\frac{[\text {conjugate base}]}{[Acid]}=758[/tex]
Therefore, the ratio of conjugate base to weak acid in the buffer system is 758: 1
Answer:
A. 1:0.46
Explanation:
I took the test
1. What are the trends for atomic size across a period and down a group for the
main group elements?
2. Draw the following Lewis structures:
a) ammonium ion b) sulfur trioxide c) hydrogen cyanide
3. Using formal charge formula (or electronegativity differences), to determine
the following the best structure, OCS, COS or CSO.
Answers
Answer:
Here's what I get
Explanation:
1. Trends in atomic size
Atomic size tends to decrease from left to right across the Periodic Table.
You are adding one electron at a time. the electrons repel each other, so the size should increase.
You are also adding a proton to the nucleus. The additional attraction should pull the electrons closer to the nucleus.
The nuclear pull wins, so the atoms get smaller from left to right
Atomic size increases from top to bottom of a Group.
You are adding electrons to an extra shell, so the size should increase.
You are also adding protons to the nucleus, so the size should decrease.
The size of the outer shell wins, so the atomic size increases going down a Group.
2. Lewis structures
(a) Ammonium ion
N is the central atom. The N atom has the positive charge.
(b) Sulfur trioxide
S is the central atom, with a double bond to each of the three O atoms.
(c) Hydrogen cyanide
C is the central atom, with a triple bond to the N atom.
3. COS
The best structure is that of O=C=S. It has no formal charges.
The Lewis structures for the other arrangements have formal charges.
The correct answers of this question is given below.
1. The atomic size increases going down a Group.2. (a) Ammonium ion : The N atom has the positive charge. (b) Sulfur trioxide : Having double bond to each of the three O atoms. (c) hydrogen cyanide : Having a triple bond to the N atom.3. COS and it has no formal charges What is Periodic table?A table in which the chemical elements are arranged in order of increasing atomic number.A periodic table has 118 known elements The chemical elements are arranged from left to right and top to bottom in order of increasing atomic number.What is the explanation for this answers?1. Trends in atomic size : Atomic size tends to decrease from left to right across the Periodic Table.You are adding one electron at a time. the electrons repel each other, so the size should increase.You are also adding a proton to the nucleus. The additional attraction should pull the electrons closer to the nucleus.The nuclear pull wins, so the atoms get smaller from left to right.Atomic size increases from top to bottom of a Group.Adding electrons to an extra shell, so the size should increaseAdding protons to the nucleus, so the size should decrease.The size of the outer shell wins, so the atomic size increases going down a Group.2. Lewis structures :
(a) Ammonium ion : N is the central atom. The N atom has the positive charge. (b) Sulfur trioxides : S is the central atom, with a double bond to each of the three O atoms.(c) Hydrogen cyanide: C is the central atom, with a triple bond to the N atom3. COS
The best structure is that of O=C=S. It has no formal charges.The Lewis structures for the other arrangements have formal charges.Learn more about atomic size below,
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Which of the following is a chemical reaction?
1- Dropping a sliced orange into a vat of Sodium Dydroxide
2-Cutting a piece of paper into two pieces
3-Filling a balloon with air
4-Freezing liquid Mercury
Answers
Answer:
1- Dropping a sliced orange into a vat of Sodium Dydroxide
Explanation:
The other answers (2-4) are only physical changes that don't change any chemical compositions.
Frosted glass and wax paper are ____.
A) transparent
B) translucent
C) clear
D) opaque
Answers
Answer:
B) translucent
Explanation:
Light only partially passes through them.
Compare and contrast the dynamics of energy transfer between the Eocene Period and the Cryogenian Period. In which period would you say that Earth's system is experiencing a net gain in energy and in which period would you say that Earth's system is experiencing a net loss in energy
Answers
Answer:
The Eocene Period is experiencing net gain in energy while Cryogenian Period is experiencing a net loss in energy.
Explanation:
In Eocene Period, the population of mammals such as horses , whales and bats etc were high due to the presence of high amount of food and good atmospheric condition such as high temperature while the population of animals were low in Cryogenian Period due to the presence of very low temperature which experiencing loss of energy. Most of area of the earth consist of icy desert.
The _____ of a weak acid is strong.
a. conjugate acid
b. conjugate base
c. acid
d. base
Answers
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]
EMERGENCY: I WILL FAIL: PLS HELP WILL MARK BRAINLIEST JUST PLS HELP
Answers
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:
Which of the following is a chemical property of liquid water?
Its density is 1.00 g/cm3.
It reacts with sodium metal to form sodium hydroxide and hydrogen gas
It flows.
It freezes to form ice.
It boils at 100°C.
Answers
Answer:
B) it reacts with sodium metal to form sodium hydroxide and hydrogen gas
Explanation:
B is the only option that show a chemical property, density, freezing, and boiling points are physical properties.
what two factors does elastic potential energy depend upon
Answers
Answer: Spring constant k as well as the distance stretched
Explanation:
Elastic potential energy is Potential energy stored as a result of deformation of an elastic object, such as the stretching of a spring. It is equal to the work done to stretch the spring, which depends upon the spring constant k as well as the distance stretched.
a put question in screen shot
Answers
Answer:maybe 2
Explanation:
Answer:
2
Explanation:
11. Calculate the energy required to produce 12.00 mol of CI207 on the basis of the
following balanced equation.
2012(g) + 702(g) + 130 kcal yields 201207(9)
Answers
Answer: 780 kcal are required to produce 12.00 mol of [tex]Cl_2O_7[/tex]
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and written along with reactants.
The balanced chemical reaction is:
[tex]2Cl_2(g)+7O_2(g)+130kcal\rightarrow 2Cl_2O_7(g)[/tex]
According to stoichiometry :
2 moles of [tex]Cl_2O_7[/tex] are produced by absorption of energy = 130 kcal
Thus 12.00 moles of [tex]Cl_2O_7[/tex] are produced by absorption of energy = [tex]\frac{130}{2}\times 12.00=780kcal[/tex]
Thus 780 kcal are required to produce 12.00 mol of [tex]Cl_2O_7[/tex]
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
Answers
Answer:
B) is the correct answer
Describe the interactions with the Sun, Earth and Moon system that result in Lunar Cycle / Phases.
Answers
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:
Explain the different principles that allow roller coasters to rip and roar around the tracks. In your response, include how energy is transferred back and forth between kinetic and potential.
Answers
Answer:
In the roller coasters the potential energy that is given is the gravitational potential energy, which this energy increases its value as the object moves away from the earth, that is to say, the more height the roller coaster acquires the more gravitational potential energy it will have, and Said train where people usually get on the roller coaster will descend or descend with greater acceleration.
This gravitational potential energy once the mountain begins to descend or descend is converted into kinetic energy
Explanation:
This that we wrote above is considering that the roller coaster does not have curved routes but rectilinear, in the case that it had curved routes, a force would be added in addition to those written that is the centripetal force, it is the same force that appears in the centrifuges or dryers of clothes or the same washing machine. This force, the centripetal force is the force that draws a moving object, in a curvilinear path, towards the center of the curvature.
