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## -What is the mole fraction of Nitrogen? A. 0.056 B. 0.167 C. 0.667 D. 0.611 E. 0.733 -What is the mole fraction of carbon dioxide A. 0.056 B. 0.067 C. 0.256 D. 0.667 E. 0.757 -What is the mole fraction of Oxygen? A. 0.167 B. 0.267 C. 0.278 D. 0.467 E. 0.578

-What is the mole fraction of Nitrogen? A. 0.056 B. 0.167 C. 0.667 D. 0.611 E. 0.733 -What is the mole fraction of carbon dioxide A. 0.056 B. 0.067 C. 0.256 D. 0.667 E. 0.757 -What is the mole fraction of Oxygen? A. 0.167 B. 0.267 C. 0.278 D. 0.467 E. 0.578

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## If nitrogen and hydrogen combine in a synthesis reaction, what would the product of the reaction be?

If nitrogen and hydrogen combine in a synthesis reaction, what would the product of the reaction be?

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## In the carbon cycle, decomposition is the breakdown of a substance into simpler substances. What is the name for the process of the nitrogen cycle that produces ammonia?

In the carbon cycle, decomposition is the breakdown of a substance into simpler substances. What is the name for the process of the nitrogen cycle that produces ammonia?

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## In 1987 the first substance to act as a superconductor at a temperature above that of liquid nitrogen (77 k) was discovered. the approximate formula of this substance is yba2cu3o7. calculate the percent composition by mass of this material.

The molar mass of the elements are:

Yttrium (Y) = 88.91 g / mol

Barium (Ba) = 137.33 g / mol

Copper (Cu) = 63.55 g / mol

Oxygen (O) = 16 g / mol

Calculating for the molar mass of YBa2Cu3O7:

YBa2Cu3O7 = 88.91 + 2(137.33) + 3(63.55) + 7(16) = 666.22
g / mol

The masses of the elements in 1 mole of YBa2Cu3O7 are:

Yttrium (Y) = 88.91 g / mol (1 mole) = 88.91 g

Barium (Ba) = 137.33 g / mol (2 mole) = 274.66 g

Copper (Cu) = 63.55 g / mol (3 mole) = 190.65 g

Oxygen (O) = 16 g / mol (7 mole) = 112 g

We now calculate for the percent composition by mass of
each element:

% Y
= 88.91 g / 666.22 g = 13.35%

% Ba
= 274.66 g / 666.22 g = 41.23%

%Cu
= 190.65 g / 666.22 g = 28.62%

%O =
112 g / 666.22 g = 16.81%

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## – How many moles of NaHCO3 can be produced from 125 mol of NaCl – How many moles Of H2O are produced when 6 mol of O2 is consumed in burning methyl alcohol, CH3OH, according to the following equation? – Solutions of iron(III) chloride, FeCl3, are used in photoengraving and to make ink. This compound can be made by the following reaction. a. How many moles of FeCl3 form from 31 mol of Cl2? b. How many moles of Fe are needed to combine with 5 mol of Cl2 by this reaction? c. If 0.62 mol of Fe is to be used by this reaction, how many moles of FeCl3 form? – Ammonia is produced synthetically by the reaction: a. Is this an exothermic or endothermic process? b. How many moles of NH3 are formed when 1 mol of N2 reacts with hydrogen? c. If 18 x 1023 molecules of H2 react with nitrogen, how many moles of NH3 are produced?

A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

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## Determine the empirical formula for a compound that is 70.79% carbon, 8.91% hydrogen, 4.59% nitrogen, and 15.72% oxygen.

Determine the empirical formula for a compound that is 70.79% carbon, 8.91% hydrogen, 4.59% nitrogen, and 15.72% oxygen.

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## Nitrogen dioxide, NO2(g) (30Hf = 33.84 kJ/mol), is decomposed according to the following reaction: What is the enthalpy change when 2.50 mol of nitrogen dioxide decomposes?

Nitrogen dioxide, NO2(g) (30Hf = 33.84 kJ/mol), is decomposed according to the following reaction: What is the enthalpy change when 2.50 mol of nitrogen dioxide decomposes?

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## Which nitrogen base sequence is the partner of T-C-A-G-C-A

1.      A.

It is a technique typically engaged in electrical power and electronic devices, wherein the devices are run at less than their rated maximum power degeneracy, taking into account the case or body temperature, the ambient temperature and the type of cooling mechanism used.

2.      B.

In order to answer the question, you need to know the area of a circle.
Area = pi * r^2
Area = 3.14 * (100/2) ^ 2
Area = 3.14 * 50^2
Area = 7850 mils^2 = 0.00785 in^2

3.      A.

V / 15 A = 0.213 Ohm
0.213 Ohm / 125 ft * 1000 ft = 1.71 Ohm / 1000 ft
Closest gauge is #12 AWG (solid wire)
#12 is 1.588 Ohm / ft, which is a 2.9775 V drop @ 15A

4.      A.

RHW cale insulation can be used up to 167 degrees F.

5.      D.

This is a type of electrical connector used to fasten two or more low-voltage (or extra-low-voltage) electrical conductors.

6.      C. the ease with which a material allows electricity to move is called CONDUCTIVITY

7.      D.

Stranded conductors are not acceptable in the pressure terminals of a duplex receptacle. Aluminum conductors of suitable gauge for a 15 ampere duplex outlet will not fit in the pressure terminal holes.

8.      D.

A 3/0 AWG THHN insulated Copper is rated at 225 amps and it falls under the 90 degree C table.

9.      D.

A #12 copper conductor with an insulation factor of 90 degrees C is rated at 20 amps. A #12 aluminum conductor with an insulation rating of 90 degrees C is rated at 15 amps. These conductors ratings only applies to three conductors in a rated at 15 amps. These conductors’ ratings only applies to three conductors in a raceway. From 7 to 24 conductors in a raceway, both aluminum and copper conductor’s ratings have to be reduced by .70, so 15 amps x .7 = 10.5 amps and 20 amps x .7 = 14 amps respectively.

10.  A.

NEC 310.15(B)(1) and (2), table 310.15(B)(2)(a), and table 310.15(B)(17).
Convert 158°F to C result is 70°C. 50 amps x .33 correction factor = 16.5 amps

11.  A.

12.  B.

Ideally, nm or armored cable should be installed in a wall stud at least 1 1/4 inches from the front edge of the stud.

13.  C.

Always use flux for electrical connections and never use acid flux on electrical connections

14.  D.

In wire gauge, the lower the number, the larger the diameter. So a 6 gauge is larger than 12 gauge, but smaller than 4 gauge.

15.  A.

16.  D.

17.  C.

Table 310-16 NEC

18.
MCM means 1000’s (M) of (C)ircular (M)ils

19.  D.

Rubber tape is used to round sharp edges

20.  B.

The larger the diameter, the larger the ampacity, or the ability to carry current.

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## When 4.50 L of hydrogen gas react with an excess of nitrogen gas at standard temperature and pressure, how many liters of ammonia gas will be produced?

When 4.50 L of hydrogen gas react with an excess of nitrogen gas at standard temperature and pressure, how many liters of ammonia gas will be produced?

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## Converting carbon to nitrogen by increasing the number of protons from 6 to 7 and decreasing the number of neutrons from 8 to 7 is an example of what type of decay? beta decay positron emission electron capture alpha decay

Converting carbon to nitrogen by increasing the number of protons from 6 to 7 and decreasing the number of neutrons from 8 to 7 is an example of what type of decay? beta decay positron emission electron capture alpha decay

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## In ammonia, a central nitrogen atom is bonded to three hydrogen atoms. Similarly, boron trifluoride has a central boron atom bonded to three fluorine atoms. However, ammonia is pyramidal and boron trifluoride is trigonal planar in shape. Which statement justifies this difference in their structure?

The balanced chemical reaction is as shown below,

N₂ + 3H₂  –> 2NH₃

The equation shows that every 3 moles of hydrogen, H2, there would be 2 moles of ammonia, NH3, that is going to be formed. Using this concept, we solve for the unknown in this item.

Since we are restricted only of the number of hydrogen, it becomes our limiting reactant.

(6 moles H2) x (2 moles NH3/3 moles H2) = 4 moles NH3

Therefore, given enough amount of N2, the amount of NH3 that can be formed out of the 6 moles of H2 is equal to 4 moles.

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## A substance contains 35.0 g nitrogen, 5.05 g hydrogen, and 60.0 g of oxygen. how many grams of hydrogen are there in a 153-g sample of this substance

0.300 M IKI represents the
concentration which is in molarity of a potassium iodide solution. This means
that for every liter of solution there are 0.300 moles of potassium iodide. Knowing
that molarity is a ratio of solute to solution.

By using a conversion factor:

100 ml x (1L / 1000 mL) x (0.300
mol Kl / 1 L) x (166.0g / 1 mol Kl) = 4.98 g

Therefore, in the first
conversion by simply converting the unit of volume to liter, Molarity is in L
where the volume is in liters. The next step is converted in moles from volume
by using molarity as a conversion factor which is similar to how density can be
used to convert between volume and mass. After converting to moles it is simply
used as molar mass of Kl which is obtained from periodic table to convert from
mole to grams.

In order to get the grams of IKI
to create a 100 mL solution of 0.600 M IKI, use the same formula as above:

100 ml x (1L / 1000 mL) x (0.600
mol Kl / 1 L) x (166.0g / 1 mol Kl) = 9.96 g

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## How many moles of electrons are required to reduce one mole of nitrogen gas (N2) to two moles of nitrogen ions (N3-)?

The balanced chemical reaction is as shown below,

N₂ + 3H₂  –> 2NH₃

The equation shows that every 3 moles of hydrogen, H2, there would be 2 moles of ammonia, NH3, that is going to be formed. Using this concept, we solve for the unknown in this item.

Since we are restricted only of the number of hydrogen, it becomes our limiting reactant.

(6 moles H2) x (2 moles NH3/3 moles H2) = 4 moles NH3

Therefore, given enough amount of N2, the amount of NH3 that can be formed out of the 6 moles of H2 is equal to 4 moles.

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## A model used for the yield y of an agricultural crop as a function of the nitrogen level n in the soil (measured in appropriate units) is y = kn 1 + n2 where k is a positive constant. what nitrogen level gives the best yield?

14. E 2.0 m/s^2

Initially, a 20 N force is applied to the block, so it has an acceleration of 3.9 m/s^2. According to Newton’s law, the mass of the block is:

In the second situation, a force of 10 N is applied to the block. Since the mass is still the same, the acceleration now is:

So, approximately 2.0 m/s^2.

15. C. 866 N at 78.1° counterclockwise to the x-axis

Resultant along the x- and y-axis:

Magnitude and direction of the resultant:

16. D. 1720 N

Since the sphere is suspended, it is in equilibrium, therefore the tension in the chain is equal to the weight of the sphere attached to it, therefore:

17. C. A

This arrangement generates the largest tension in the chain, because in all other arrangements the weight of the object is split between the two chains, while in this case all the weight is hold by one chain, therefore the tension in this case is larger.

18. Straight path

The gravity “holds” the planets keeping them in a circular orbit. If we remove gravity, the planets would continue in a straight path with constant speed, because now there are no more forces acting on it, so by inertia they will continue their uniform motion with constant speed.

19. B. 1.6 × 104 N

First we can find the deceleration of the car by using the SUVAT equation:

where v=0 m/s, u=2 m/s, and S=15 cm=0.15 m. Re-arranging, we have

And now we can calculate the average force exerted on the car, by using Newton’s second law:

(the negative sign means that the force’s direction is opposite to the motion of the car)

20. A. magnetism

Magnetism is part of the electromagnetic force, which is one of the fundamental forces which act also through empty space. All the other forces need some object in order to act.

21. E. 45 N

The magnitude of the force in link A is equal to the weight of the rod plus the weight of the lower block, therefore:

22. C. on Earth at sea level

The weight of the bowling ball is given by: , where m is the mass of the ball and g is the acceleration due to gravity. The value of g increases when moving from the Earth’s center to the Earth’s surface, then decreases when moving far from the surface, so the point where g is greatest is at sea level, where it is 9.81 m/s^2. On the surface of the Moon, g is much smaller (about 1/6 of the value on Earth).

23. A. 0.5 m/s2

The acceleration of the block is given by Newton’s second law:

24. D. Both forces are equal in magnitude but opposite in direction.

According to Newton’s third law: if an object A exerts a force on an object B, then object B exerts a force equal and opposite on object B. In this case, objects A and B are the bat and the baseball, therefore the two forces are equal in magnitude and opposite in direction.

25. B. 2940 N

The mass of the boulder is equal to its weight divided by the acceleration of gravity (9.81 m/s^2):

So now we can calculate the force needed to accelerate the boulder to 12.0 m/s^2:

26. D. 32.2 N

The weight of the object on Mercury is given by:

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## The process in which nitrogen is converted into a usable form for life is called _______. a. nitrogen fixation b. photosynthesis c. greenhouse effect d. photolysis

The correct answer would be a multicellular organism.

Explanation:

Any organism that can contain upto 5 levels of the organization is can be termed as multicellular as they comprise many cells to form different levels of the organization.

The different levels of organization of an organism in order are cellular level, tissue level, organ level, organ system, and a complete organism. All these organization levels are made of cells, cells make the tissue by joined together, different tissues joined together to form organs. different organs joined to make a functional organ system that ultimately makes an individual with different organ systems such as the digestive system, respiratory system and other.

Thus, the correct answer would be a multicellular organism.

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## What is the partial pressure of argon gas in a sealed vessel that has a total pressure of 1514 psi and partial pressures of 325 psi for oxygen and 649 psi for nitrogen?

What is the partial pressure of argon gas in a sealed vessel that has a total pressure of 1514 psi and partial pressures of 325 psi for oxygen and 649 psi for nitrogen?

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## The equation below shows lithium reacting with nitrogen to produce lithium nitride. 6Li + N2 mc007-1.jpg 2Li3N If 12 mol of lithium were reacted with excess nitrogen gas, how many moles of lithium nitride would be produced? 4.0 mol 6.0 mol 12 mol 36 mol

1 mol is (always) the same number of units: 6.02 * 10^23 units.

So 0.5 moles  of any gas has the same number of molecules.

Also, we know by the ideal gas laws that a give number of molecules of any gas will occupy the same volume.

Given that the three gases have the same number of atoms in the molecular fomula (2), 0.5 moles will also have the same number of atoms.

g.f.w. stands for grams formula weight and that is different for all of them, because gfw is calcualted from the atomics masses of each atom in the molecule.

Then at STP (standard temperature and pressure) conditions 0.50 moles of any of the gas:

– will contain the same number of molecules,

– will contain the same number of atoms

– will occupy the same volume.

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## Water vapor is lighter than many atmospheric gases such as oxygen, nitrogen, and carbon dioxide. why then doesn’t water vapor rise above these other gases to a higher level of the atmosphere?

The choices that are originally attached to the question you provided is as follows:

Water vapor contains other elements that give it weight.

The cool atmosphere condenses the rising water vapor and causes it to fall back to Earth.

The water molecules are attracted to the molecules of heavier gases and remain in the lower regions of the atmosphere.

There is an attraction among the water vapor molecules to hold them together close to Earth.

By definition, a water vapor is the gaseous representation of water in which the product of the evaporated liquid water. Therefore, the answer would be the fourth choice.

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## Air contains 78 percent, nitrogen 21 percent oxygen, and one percent argon. Which gas is the solvent? oxygen nitrogen argon none of the above

Air contains 78 percent, nitrogen 21 percent oxygen, and one percent argon. Which gas is the solvent? oxygen nitrogen argon none of the above

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## Scientists believe that the earth's early atmosphere lacked __________ gas because photosynthetic organisms did not yet exist. a hydrogen b nitrogen c oxygen d sulfur

Scientists believe that the earth’s early atmosphere lacked __________ gas because photosynthetic organisms did not yet exist. a hydrogen b nitrogen c oxygen d sulfur

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## Which of the following is a pollutant that is measured by the Air Quality Index? A. Methane B. Nitrogen dioxide C. Carbon dioxide D. Nitrous oxide

The Air Quality Index (AQI) is an index for reporting daily air quality.The higher the AQI value, the greater the level of air pollution and the greater the health concern. Nitrogen dioxide is a pollutant that is measured by the Air Quality Index. Correct answer: B Besides nitrogen dioxide AQI measures also the following four five criteria air pollutants: particulate matter, sulfur dioxide, carbon monoxide, and ozone.

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## Which of the following would be a result of eutrophication of nitrogen? A.undergrowth of water plants B.hypoxia, or low levels of oxygen C.decreased decomposition D.inactivity of fertilizers

Hello!! If you were looking for some answers on the honors biology from microorganisms to plants unit test for WACA; here are the answers I know

(sorry to those that don’t meet these requirements)

1. the answer is: vary greatly in size and structure

2. the answer is: water-conducting tissue

3. the answer is: cycle 1 shows asexual reproduction in green algae

6. the answer is: are carried to female reproductive structure by wind or animals

8. embryo, seed, fruit

9. they should use antibiotics only when necessary

10. prokaryotes are different from eukaryotes because prokaryotic cell lack DNA; the answer is: false

11. protists are a diverse group of mainly multicellular prokaryotes; the answer is: false

12. cilia and flagella are similar in that they are both made of microtubules; the answer is: true

13. water molds reproduce asexually using conjugation; the answer is: false

14. xylem carries solutions of nutrients and food produced by photosynthesis; the answer is: false

15. in angiosperms, the ovule become the fruit; the answer is: false

16. when plants pump nutrients from their roots to their branches, the roots contain the sink cells; the answer is: false

17. cells on the shaded side of a stem elongate more than the cells on the side receiving light because of the hormone ethylene; the answer is: false

Gook luck to those who meet these requirements! I was SO not a fan of this test, I’ll see what I got right for questions 19-36 and update where I can!

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## Bacteria are responsible, in some way, for all BUT one of the processes in Earth’s environment. That is A) photosynthesis. B) phosphorylation. C) recycling carbon. D) nitrogen fixation.

Greek philosopher “Pythagoras” first proved that it is round or spherical.

Explanation:

Ancient astronomers thought that earth is flat one of the strong beliefs of this is found in early “Egyptian thoughts” which believed the earth is the floating disk between the ocean.

These are some more options of this belief:

A) Earth is at the center of the solar system.

B) The moon and the sun are spherical in shape.

C) There are days and nights and seasons on Earth.

D) Earth’s shadow on the moon shows it is spherical.

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