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Which of the following particles has mass? a. protons only b. electrons only c. both protons and electrons

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Which of the following particles has mass? a. protons only b. electrons only c. both protons and electrons

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Which of the following have electrical charge? a. protons and neutrons b.neutrons and electrons c. electrons and protons

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Which of the following have electrical charge? a. protons and neutrons b.neutrons and electrons c. electrons and protons

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Electrons contribute ______________ charge and ______________ mass to the atom. a.negative, a lot of b. little, a lot of c.negative, little

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Electrons contribute ______________ charge and ______________ mass to the atom. a.negative, a lot of b. little, a lot of c.negative, little

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HELP PLEASE! 3 SCIENCE QUESTIONS! I'm stuck on my last 3. #1 Compare and contrast chemical change and physical change. #2 Compare and contrast a gas and a plasma. #3 What state of matter has the electrons separated from the nuclei of the atoms? Gas Solid Liquid Plasma

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HELP PLEASE! 3 SCIENCE QUESTIONS! I’m stuck on my last 3. #1 Compare and contrast chemical change and physical change. #2 Compare and contrast a gas and a plasma. #3 What state of matter has the electrons separated from the nuclei of the atoms? Gas Solid Liquid Plasma

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You have two pieces of wire that allow electrons to pass through them when they arfe connected to each other. if you insert cable betwee the wires, electrons will flow easily. the metal cable is?

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You have two pieces of wire that allow electrons to pass through them when they arfe connected to each other. if you insert cable betwee the wires, electrons will flow easily. the metal cable is?

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Atoms contain charged particles called protons and electrons. Each proton has a charge of +1, and each electron has a charge of –1. A sulfur ion has 16 protons and 18 electrons. Find the net charge.

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Atoms contain charged particles called protons and electrons. Each proton has a charge of +1, and each electron has a charge of –1. A sulfur ion has 16 protons and 18 electrons. Find the net charge.

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Which statement best describes the difference between strong nuclear forces and weak nuclear forces? a) Weak nuclear forces hold protons and neutrons together; strong nuclear forces hold electrons in their shells. b) Strong nuclear forces are responsible for holding electrons in bonds; weak nuclear forces are involved when the bonds break. c) Weak nuclear forces hold the atoms’ nucleus together; strong nuclear forces tear them apart. d) Strong nuclear forces are responsible for holding together the nucleus of an atom; weak nuclear forces are involved when certain types of atoms break down.

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There are four types of fundamental forces in nature.These are named as gravitational force,electromagnetic force,strong nuclear force and weak nuclear force.

As per the question we have to understand the role of strong nuclear force and weak nuclear force.

An atom consists of a nucleus surrounded by extra nuclear part consisting of electrons in various orbits.The nucleus contains two basic particles called protons and neutrons .Protons are positively charged while neutrons are neutral.Protons being positively charged will impart repulsive force on each other and may come out of the nucleus.But the nucleus is stable.That is due to the strong nuclear force.

Strong nuclear force is a spin dependent and charge independent force which comes into existence due to the mutual interaction of gluons which binds the protons and neutrons .Hence it is attractive in nature.It’s 100 times more stronger than electromagnetic force also.

Weak nuclear force comes into existence during radio -active decay .This force is due to the exchange of ‘ w’ and ‘z’ bosons[the particles like protons and neutrons having integral or zero spin] which are heavier in nature.The role of it is to change protons into neutrons and vice versa.Its a short range force.

Hence the option D is right.

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What is the name given to the electrons in the highest occupied energy level of an atom?

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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

Answer: 47 kJ/mol

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The atoms of which elements are most likely to share many electrons among many Atoms

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Answer:

d. All the organisms in an ecosystem share distribution patterns.

Explanation:

Native range is what is known in biology as the areas where a species is naturally found, not places were humans introduced them, species have some range only for breeding, for example some frogs only go into the rapids for breeding, and not for living or hunting, and seasonal ranges are areas where the species are found for a part of the year, for example the butterflies that migrate south to Mexico on the coldest months of the year and then come back to the United States for the warm summer, the only one that is not true is that all the organisms in an ecosystem share distribution patterns.

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In which type of chemical bonding are electrons shared among all atoms in the substance?

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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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An atom of the element iron has an atomic number of 26 and an atomic mass number of 56. if it is neutral, how many protons, neutrons, and electrons does it have?

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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The second shell in the ground state of atomic argon contains ________ electrons.

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The second shell in the ground state of atomic argon contains ________ electrons.

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How can a sample of uranium-235 that has critical mass be induced to react? it must be spilt with a laser. it must be fused to a helium nucleus. it must be bombarded with neutrons. it must be shot with light speed electrons?

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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After scientists discovered electrons and protons, what led them to believe there was a third subatomic particle? A. Elements have molar masses that are numerically equal to their atomic mass. B. The mass of an atom’s nucleus is greater than the combined masses of an atom’s protons. C. The mass of an atom is greater than the combined masses of an atom’s protons and electrons. D. Elements have isotopes that have the same atomic number but different atomic mass numbers.

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The unknown of this problem is the experimental percent of water in the compound in order to remove the water of hydrogen, given the following:

Mass of crucible, cover and contents before heating                               23.54 g
Mass of empty crucible and cover                                                            18.82 g
Mass of crucible, cover, and contents after heating to constant mass     20.94 g

In order to get the answer, determine the following:

Mass of hydrated salt used                          = 23.54 g – 18.82 g = 4.72 g
Mass of dehydrated salt after heating          = 20.94 g – 18.82 g = 2.12 g
Mass of water liberated from salt                 = 4.72 g – 2.12 g = 2.60 g

Then solve the percent of water in the hydrated salt by:

% water = (mass of water / mass of hydrated salt) x 100
% water = 2.60 g / 4.72 g x 100
% water = 55.08 % in the compound 

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In the covalent bond between hydrogen and chlorine in the HCl molecule, where will the majority of shared electrons be found? A.near the hydrogen atom B.near the chlorine atom C.equidistant from both atoms D.away from chlorine atom E.away from both atoms

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When ammonia is added with water, it forms a lonely OH- ion and a conjugate acid of HNH3+, or NH4+. Just based on the formula alone, a basic hydroxide is one of the products from NH3 and H2O, which is usually a tall-tale sign of NH3 being basic. Also, the reaction can also be reversed, so that (OH-)+(NH4+) -> H2O+NH3.

If this question has a different chemical formula, with either a H+ (hydrogen atom/proton) or a H3O+ (hydronium) as one of the products, then the compound that is being hydrolyzed (H2O is added to it) is acidic.

Hope this answers the question.

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Which statement defines reduction potential when considering a pair of half-cell reactions? The half-reaction with the greater SRP has a greater tendency to gain electrons. The half-reaction with the lower SRP has a greater tendency to gain electrons. If each half-reaction has an SRP greater than zero, there will be two reduction reactions. If each half-reaction has an SRP less than zero, there will be two oxidation reactions.

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Answer:

The coefficient of CO₂ is 5.

Explanation:

    Balancing the reaction:

___C₅H₁₂ + ___O₂ → ___CO₂ + ___H₂O

There are 5 C in the left side, so we put 5 on the right side:

___C₅H₁₂ + ___O₂ →  5CO₂ + ___H₂O

There are 12 H in the left side, so we put 6 as the coefficient of H₂O:

___C₅H₁₂ + ___O₂ →  5CO₂ + 6H₂O

Finally, there are 16 O in the right side, so we put 8 as the coefficient of O₂

___C₅H₁₂ + 8O₂ →  5CO₂ + 6H₂O

The coefficient of CO₂ is 5.

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The repeating subunits that are responsible for the shape of a crystal are known as unit cells. heavy nuclei. light electrons. amorphous cells.

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The repeating subunits that are responsible for the shape of a crystal are known as unit cells. heavy nuclei. light electrons. amorphous cells.

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Which of the following best predicts the outcome of a fusion reaction involving isotopes of hydrogen?Two hydrogen isotopes form bonds with each other, absorbing a large amount of energy.The nuclei of the hydrogen isotopes join together to form a heavier element, and energy is released.Isotopes of hydrogen absorb electrons, undergo an increase in energy level, and split into fragments.The nuclei of the hydrogen isotopes split, resulting in smaller fragments and the release of a large amount of energy.

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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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Which of the following elements has the fewest valence electrons? beryllium boron carbon lithium The answer is lithium but someone had the same question and someone answered wrong. Lithium only has on valence electron while beryllium has 2, boron has 3 and carbon has 4 making lithium the correct answer

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Explanation :

In the net ionic equations, we are not include the spectator ions in the equations.

Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.

(a) The given balanced ionic equation is,

Ni(NO_3)_2(aq)+Na_2S(aq)rightarrow NiS(s)+2NaNO_3(aq)

The ionic equation in separated aqueous solution will be,

Ni^{2+}(aq)+2NO_3^-(aq)+2Na^+(aq)+S^{2-}(aq)rightarrow NiS(s)+2Na^+(aq)+2NO_3^-(aq)

In this equation, Na^+text{ and }NO_3^- are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

Ni^{2+}(aq)+S^{2-}(aq)rightarrow NiS(s)

(b) The given balanced ionic equation is,

NaNO_3(aq)+KBr(aq)rightarrow KNO_3(s)+NaBr(aq)

The ionic equation in separated aqueous solution will be,

Na^+(aq)+NO_3^-(aq)+K^+(aq)+Br^-(aq)rightarrow KNO_3(s)+Na^+(aq)+Br^-(aq)

In this equation, Na^+text{ and }Br^- are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

NO_3^-(aq)+K^+(aq)rightarrow KNO_3(s)

(c) The given balanced ionic equation is,

Li_2SO_4(aq)+BaCl_2(aq)rightarrow BaSO_4(s)+2LiCl(aq)

The ionic equation in separated aqueous solution will be,

2Li^+(aq)+SO_4^{2-}(aq)+Ba^{2+}(aq)+2Cl^-(aq)rightarrow BaSO_4(s)+2Li^+(aq)+2Cl^-(aq)

In this equation, Li^+text{ and }Cl^- are the spectator ions.

By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.

The net ionic equation will be,

SO_4^{2-}(aq)+Ba^{2+}(aq)rightarrow BaSO_4(s)

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Which of the following describes an insulator? A.Does not allow electrons to move through it B.Allows electrons to move through it C.Is always a solid D.Is always a gas

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There are two systems in the human body that are responsible for the coordination between the functions of different systems to achieve the unity of the living organism’s body. These two systems are the nervous system and the endocrine system. The action of the nervous system is fast and takes a short time, while the action of the endocrine system is slow and takes a long time.

The functional unit of the nervous system is the nerve cell or the neuron. The neuron consists of a cell body and the axon. The cell body starts with the dendrites that receive the messages or the impulses from other neurons or from different sense organs or receptors. These impulses are then transmitted through the cell body. The cell body contains a nucleus and different organelles which help the nerve cell to perform its functions. The nerve impulse is then transmitted to the axon.

The axon is an extension from the cell body. There are some cells called Schwan cells that secrete a myelin sheath to insulate the axon from the surrounding medium. The insulated axons have more ability to conduct the impulses than non-insulated axons. The axon ends with the terminal arborizations. The terminal arborizations of a nerve cell connect to the dendrites of the next cell or to the afferent organ. The gaps between the dendrites and the terminal arborizations are called the synapses.

The nerve impulse is an electrochemical phenomenon i.e. an electrical phenomenon with a chemical nature. The membrane of the axon acts as a barrier between an outside positively charged medium and an inside negatively charged medium. This makes a potential difference of  -70mV. This state is called the resting potential. When the membrane is subjected to a stimulus, the positive charges enter to inside and the negative charges exit to the outside. The potential difference now becomes +40mV. This state is called the depolarization state. The point of stimulation acts as a new stimulus for the next point and so on. The membrane sooner gains its permeability again and the positive charges return to the outside and the negative charges to inside. This state is called repolarization.

The nerve impulse reaches the synapse. There are some neurotransmitters that are excited by the nerve impulse coming and carry the message across the membrane. Some receptors receive theses neurotransmitters on the dendrites of the next neuron. These receptors act as a stimulus for the new cell.

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A scientist adds heat to each of the following substances. Which will probably absorb the most heat before its temperature changes significantly? 50 g of solid copper 50 g of solid iron 50 g of liquid water 50 g of sand Question 2(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid. Question 3(Multiple Choice Worth 2 points) Which of these best explains what happens when the ionic substance calcium chloride (CaCl2) dissolves in water? The oxygen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the Cl− ions. The hydrogen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the H+ ions. Question 4(Multiple Choice Worth 2 points) Which of these statements about water is true? Its atoms share electrons equally. It can dissolve all known substances. Its molecules are farther apart in the solid state than in the liquid state. It has a lower specific heat than nearly all known metals.

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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Areas near oceans or large lakes tend to have more moderate climates than do areas far from large bodies of water. Which of these statements best explains this observation? Hydrogen and oxygen atoms share electrons in a water molecule. Lakes and oceans contain dissolved solids. Water has a very high specific heat. Water produces buoyant forces. Question 2(Multiple Choice Worth 2 points) A scientist discovers a new substance. The molecules of the substance form hydrogen bonds with each other. When the molecules lose a lot of energy, the hydrogen bonds hold them relatively far apart. Based on this information, what can the scientist infer about the substance? It expands when it freezes. It is highly colored. It exists only as a gas. It does not dissolve ionic compounds. Question 3(Multiple Choice Worth 2 points) Which of the following properties of water is due primarily to the uneven distribution of charge between the hydrogen and oxygen atoms? its color its taste its ability to dissolve ionic substances its ability to produce buoyant forces Question 4(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid.

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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Which of the following describes a circuit? a loop of wire allows electrons to flow does not allow electrons to flow a closed conduction loop through which an electrical current can flow

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The equation for how temperature changes the resistance R is: 

R=R₀(1+α(T-T₀)), where R₀ is the resistance at T₀=20°C, T is the temperature for which we want to calculate the resistance and α is the temperature coefficient for resistance. 

The resistance of the copper wire increases by 18% or by 0.18, so the new value for the resistance is R=1.18*R₀.

T₀=20°C
=0.0068
R=1.18*R₀

Now we need to input that into the equation for resistance change and solve for temperature T.  

1.18R₀=R₀(1+α(T-20)), R₀ cancels out,

1.18=1+α(T-20),

1.18-1=α(T-20), we divide by α,

0.18/α=T-20, we put 20 on the left side,

26.47+20=T

T=46.47°C

So the temperature on which the resistance of copper wire will increase by 18% is T=46.47°C. 

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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-)?

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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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The two-slit diffraction experiment shows how light can be treated as particles and how light waves carry the statistical information for the experiment. if we were to use a beam of electrons instead of light in the experiment, how would the results differ?

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The two-slit diffraction experiment shows how light can be treated as particles and how light waves carry the statistical information for the experiment. if we were to use a beam of electrons instead of light in the experiment, how would the results differ?

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