What is the number of moles in 500 L of He gas at STP

Answer:

number of energy levels

Explanation:

for example hydrogen and helium are in period 1 and they have 1 energy level

Answer:

Al₄C₃ + 12H₂O ⟶ 4Al(OH)₃ + 3CH₄

Explanation:

The correct formulas are

Al₄C₃ + H₂O ⟶ Al(OH)₃ + CH₄

Often, the best way to start is to balance all atoms other than O and H, then balance O, then balance H.

1. Put a 1 in front of the most complicated-looking formula (Al₄C₃):

1Al₄C₃ + H₂O ⟶ Al(OH)₃ + CH₄

2. Balance Al:

We have fixed 4 Al on the left. We need 4 Al on the right. Put a 4 in front of Al(OH)₃.

1Al₄C₃ + H₂O ⟶ 4Al(OH)₃ + CH₄

3. Balance C:

We have fixed 3 C on the left. We need 3 C on the right. Put a 3 in front of CH₄.

1Al₄C₃ + 12H₂O ⟶ 4Al(OH)₃ + 3CH₄

4. Balance O:

We have fixed 12 O on the right. We need 12 O on the left. Put a 12 in front of H₂O.

1Al₄C₃ + 12H₂O ⟶ 4Al(OH)₃ + 3CH₄

Every formula now has a fixed coefficient. The equation should be balanced.

5. Check that atoms balance:

\[tex]\begin{array}{ccc}\textbf{Atom} & \textbf{On the left} & \textbf{On the right}\\\text{Al} & 4 & 4\\\text{C} & 3 & 4\\\text{H} & 24 & 24\\\text{O} & 12 & 12\\\end{array}[/tex]

The balanced equation is

Al₄C₃ + 12H₂O ⟶ 4Al(OH)₃ + 3CH₄

Answer:Al4C + 4(H20) = 4AL(OH) +CH4

Explanation:

the equation is balance on both sides,

4 aluminums on both sides

1 carbon on both sides

8 hydrogens on both sides

4 oxygens on both sides

Answer:

a AND b

Explanation:

The flowchart shows the order of the common states of matter as solids, liquids, and gases. To find the properties that match this order, let's examine each option:

1. Space between particles: This property refers to the distance between particles in a substance. In solids, particles are tightly packed together, so there is less space between them. In liquids, particles are less tightly packed, so there is more space between them compared to solids. In gases, particles are very spread out, so there is the most space between them. Therefore, this property matches the order of the states of matter in the flowchart.

2. Kinetic energy of particles: Kinetic energy refers to the energy of motion. In solids, particles have the least amount of kinetic energy as they vibrate in fixed positions. In liquids, particles have more kinetic energy as they move more freely, but still stay close together. In gases, particles have the most kinetic energy as they move rapidly and spread out. Therefore, this property also matches the order of the states of matter in the flowchart.

3. Density of matter: Density refers to the mass of a substance per unit volume. While the density of matter does change between the different states, it does not match the order of the states of matter in the flowchart. Solids can have a higher density than liquids, and liquids can have a higher density than gases. So, this property does not match the order shown in the flowchart.

4. Speed of particle motion: The speed of particle motion does change between the different states, but it does not match the order of the states of matter in the flowchart. The particles in solids have the slowest motion, followed by particles in liquids, and then particles in gases which have the fastest motion. So, this property does not match the order shown in the flowchart.

In summary, the properties of matter that match the order of the states of matter in the flowchart are the "space between particles" and the "kinetic energy of particles." These properties help explain the differences between solids, liquids, and gases based on how closely packed the particles are and how much they are moving.

The order of the states of matter in the flowchart is related to the space between particles and the speed of particle motion.

The flowchart represents the order of the three common states of matter: solids, liquids, and gases. As we move from solids to liquids to gases, the space between particles increases. In solids, the particles are closely packed together, whereas in liquids, the particles have some space between them, and in gases, the particles are widely spaced apart. Likewise, the speed of particle motion increases as we move from solids to liquids to gases. In solids, the particles are tightly packed and vibrate in place, in liquids, the particles move more freely and are able to slide past each other, and in gases, the particles move rapidly and randomly in all directions.

However, the density of matter does not follow the same order as the flowchart. The density of a substance depends on the mass and volume, and it can vary greatly between different substances in the same state of matter. For example, the density of lead (a solid) is much higher than the density of water (a liquid).

The kinetic energy of particles is also not directly related to the order of the states of matter in the flowchart. The kinetic energy of particles is a measure of their motion, and it can vary within the same state of matter depending on the temperature. For instance, the kinetic energy of the particles in boiling water (a liquid) is higher than that in cold water (also a liquid).

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a. lawn fertilizer runoff

 Pollution as a result of lawn fertilizer runoff would be difficult to track and regulate due to the possible breadth of the area affected. Toxins can be spread throughout the land area as well as be carried downstream if near a water source. Sewer systems, rivers, lakes, ponds, etc. can all be negatively affected by lawn fertilizer runoff. Irrigation or rain water can carry toxins for many miles before the effects are detected. Tracing the source of the toxins would be difficult, especially in a highly populated area.

Lawn fertilizer runoff is a source of pollution that would be difficult to track and regulate as compared to others.

Pollution that occurs as a result of lawn fertilizer runoff would be difficult to track and regulate because of the large size of the area. Toxins present chemical fertilizer can be spread throughout the land as well as also added to the water source.

So that's why we can say that Lawn fertilizer runoff would be more difficult to track and regulate as compared to others.

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Answer:

[tex]\boxed{\text{-2791 kJ/mol}}[/tex]

Explanation:

One way to calculate the lattice energy is to use Hess's Law .

The lattice energy U is the energy released when the gaseous ions combine to form a solid ionic crystal:

M²⁺(g) + 2X⁻(g) ⟶ MgX₂(s); U = ?

We must generate this reaction rom the equations given.

(1) M(s) + X₂ (g) ⟶ MX₂(s);      ΔHf⁰ = -985 kJ·mol⁻¹

(2) M(s) ⟶ M(g);                  ΔHsub =   135 kJ·mol⁻¹

(3) M(g) ⟶M⁺(g) +e⁻                   IE₁ =   731 kJ·mol⁻¹

(4) M⁺(g) ⟶ M²⁺(g) + e⁻             IE₂ = 1403 kJ·mol⁻¹

(5) X(g) + e⁻ ⟶ X⁻(g)                 EA =  -335 kJ·mol⁻¹

(6) X₂(g) ⟶ 2X(g)                      BE =   207 kJ·mol⁻¹

Now, we put these equations together to get the lattice energy.  Underlined species have been cancelled.

                                                        E/kJ  

(7)   M²⁺(g) + e⁻⟶ M⁺(g)                 -1403

(8)   M⁺(g) + e⁻ ⟶ M(g)                     -731

(9)   M(g) ⟶ M(s)                              -135

(10) M(s) + X₂(g) ⟶ MX₂(s)              -985

(11)  2X(g) ⟶ X₂(g)                           -207

(12) 2X⁻(g) ⟶ 2X(g) + 2e⁻               +670

     M²⁺(g) +  2X⁻(g) ⟶ MX₂(s)       -2791

The lattice energy of MX₂ is [tex]\boxed{\textbf{-2791 kJ/mol}}[/tex].

The lattice energy of the ionic compound MX2 can be calculated using the Born-Haber cycle. This accounts for various steps including the sublimation, ionization, dissociation, and electron affinity of the involved elements. In this case, the lattice energy of MX2 is 2633 kJ/mol.

The lattice energy of an ionic compound, in this case MX2, can be calculated using the Born-Haber cycle - a thermochemical cycle involving several steps where every step corresponds to a specific energy change.

The steps include: sublimation of the metal, ionization of the metal, dissociation of the halogen, addition of electrons to the halogen atoms (electron affinity), and formation of the ionic compound.

For this case, you can calculate the lattice energy of MX2 by adding the enthalpy of formation, enthalpy of sublimation, ionization energies, electron affinity (multiplied by 2 as there are 2 halogens per formula unit in MX2), and half of the bond energy (as we are breaking one X2 into two X per formula unit of MX2).

So, the lattice energy = |Δ∘f + Δsub + IE1 + IE2 + 2(ΔEA) + 0.5(BE)|.

Which gives = |-(-985 kJ/mol) + 135 kJ/mol + 731 kJ/mol + 1403 kJ/mol + 2*(-335 kJ/mol) + 0.5*207 kJ/mol| =  2633 kJ/mol. Therefore, the lattice energy of MX2 is 2633 kJ/mol.

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Answer:

[tex]\boxed{\text{6 mol}}[/tex]

Explanation:

(a) Balanced equation

2Zn + O₂ ⟶ 2ZnO

(b). Calculation

You want to convert moles of ZnO  to moles of Zn

The molar ratio is 2 mol Zn:2 mol ZnO

[tex]\text{Moles of Zn} =\text{6 mol ZnO} \times \dfrac{\text{2 mol Zn}}{\text{2 mol ZnO}} = \text{6 mol Zn}\\\\\text{You need }\boxed{\textbf{6 mol of Zn}}\text{ to form 6 mol of ZnO}.[/tex]

To make 6 moles of zinc oxide, you would need 6 moles of zinc based on the balanced chemical equation 2Zn + O2 → 2ZnO.

Answer: Sharp spines and waxy stems

Sharp spines because it keeps predators away and it’s skin helps keep in water

Energy transfer in waves involves a disturbance that propagates through a medium, causing particle oscillation and energy transmission. For example, sound waves transfer energy through air via compression and expansion of air molecules. Waves do not move the particles but rather transfer energy through them.

Energy transfer in waves involves the propagation of a disturbance through a medium. This disturbance causes particles of the medium to move away from their equilibrium position, transferring energy from one particle to the next. This transfer occurs as the wave travels through the medium, causing the particles to oscillate back and forth.

For example, in acoustics, energy is transferred via vibrational waves. When a sound wave travels through the air, it compresses and expands air molecules, creating pressure variations that propagate through the medium as a longitudinal wave. These oscillations result in a transfer of energy from the source of the sound to the receiver.

Generally, a wave does not transport the particles of the medium over a distance, but it does transmit energy and momentum. Key characteristics of waves include a disturbance in space and time and a medium with elasticity that can return to equilibrium after deformation.

Types of Waves

Answer: The energy in fossil fuels is often converted into Electrical Energy or more simply, electricity

The energy in fossil fuels is often converted into different forms of energy, such as thermal, mechanical and electrical energy. This is most commonly achieved through burning fossil fuels, which releases thermal energy that can be used to drive steam engines or to generate electricity.

The energy in fossil fuels is often converted into several other forms of energy, most notably heat or thermal energy. This conversion of energy from one form into another happens all the time. For example, when fossil fuels such as coal, petroleum or natural gas are burned, the chemical energy they contain is converted into thermal energy. This thermal energy can then be used to heat buildings or to operate steam-driven machinery which then converts the thermal energy into mechanical energy. In electric power plants, this mechanical energy is further converted into electrical energy by rotating coils of wire in magnetic fields to generate electricity. It is important to note that not all of the initial energy is converted into the forms mentioned, as some energy is always transferred to the environment.

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Answer:c

Explanation:

Answer:

The correct answer is option C, that is, Aboriginals and Maori.

Explanation:

The two prime groups of people, which have inhabited the islands south of Oceania are the Maori and the Aboriginals. The Maori refers to a group of individuals, which have settled in the South and North islands of New Zealand, while the Aboriginals refers to a group of individuals, which have inhabited Australia about forty thousand years ago.

The answer is:

The temperature will be the same, 37°C.

Since from the statemet we know the first temperature, pressure and volumen of a gas, and we need to calculate the new temperature after the pressure and the volume changed, we need to use the Combined Gas Law.

The Combined Gas Law establishes a relationship between the temperature, the pressure and the volume of an ideal gas using Boyle's Law, Gay-Lussac's Law and Charles's Law.

The law establishes the following equation:

[tex]\frac{P_{1}V{1}}{T_{1}}=\frac{P_{2}V{2}}{T_{2}}[/tex]

Where,

[tex]P_{1}[/tex] is the first pressure.

[tex]V_{1}[/tex] is the first volume.

[tex]T_{1}[/tex] is the first temperature.

[tex]P_{2}[/tex] is the second pressure.

[tex]V_{2}[/tex] is the second volume.

[tex]T_{2}[/tex] is the second temperature.

Then, we are given the following information:

[tex]V_{1}=200mL\\P_{1}=4atm\\T_{1}=37\°C\\V_{2}=400mL\\P_{2}=2atm[/tex]

So, isolating the new temperature and substituting the given information, we have:

[tex]\frac{P_{1}V{1}}{T_{1}}=\frac{P_{2}V{2}}{T_{2}}\\\\T_{2}=P_{2}V{2}*\frac{T_{1}}{P_{1}V_{1}} \\\\T_{2}=2atm*400mL*\frac{37\°C}{4atm*200mL}=37\°C[/tex]

Hence, we have that the temperature will not change because both pressure and volume decreased and increased proportionally, creating the same relationship that we had before the experiment started.

The temperature will be the same, 37°C

Have a nice day!

Partial pressure is what the scientist would measure. 100%

Answer:

D

Explanation: its brackin cuz

The reaction between sodium bicarbonate and sulfuric acid produces sodium sulfate, carbon dioxide, and water, as represented by the balanced chemical equation: NaHCO3 + H2SO4 → Na2SO4 + CO2(g) + 2H2O(l).

The word equation for the overall reaction occurring in the baggie, with sodium bicarbonate as a reactant, would typically be something like:

sodium bicarbonate + acid → sodium salt + water + carbon dioxide

When sodium bicarbonate (NaHCO3) is reacted with sulfuric acid (H2SO4), the balanced chemical equation for the reaction in the baggie would be:

NaHCO3 + H2SO4 → Na2SO4 + CO2(g) + 2H2O(l)

This shows sodium bicarbonate reacting with sulfuric acid to produce sodium sulfate, carbon dioxide gas, and water.

Answer:

It is options A and D.

Explanation:

Did the assignment.

Final answer:

The reliable sources from the given options are the article by the United States Geological Survey and the study published in the Journal of Medicinal Chemistry, both of which are credible due to their authoritative and scholarly quality.

Explanation:

Among the given options, the following sources are considered reliable:

Reliable sources are essential for research and credible, trustworthy, and unbiased information. These sources guarantee that the evidence and facts presented support the conclusions drawn. The USGS is a reputable government agency known for its research and the publication of scholarly articles, making it a credible source. The Journal of Medicinal Chemistry is part of the peer-reviewed academic publications, which are often published by academic institutions or associations, ensuring a rigorous process of review that adds to their credibility.

Some sources, such as a blog by a non-expert or a publicly editable encyclopedia, lack authoritative oversight and therefore are not as trustworthy. To ensure credibility, consulting multiple reliable sources is recommended, and sources like reputable newspapers, magazines, academic journals, and government publications are generally reliable.

The answer is:

Hence, the new pressure will be 2.07 atm.

[tex]P_{2}=2.07atm[/tex]

Since we know that the gas is inside of a rigid container, meaning that the volume will be kept constant, we can solve the problem using the Gay-Lussac's Law.

The the Gay-Lussac's Law establishes that when an ideal gas is kept at the same volume, the pressure and the temperature will be proportional.

We need to pay special attention when we are working with the Gay-Lussac's Law since its equaitons works with absolute temperatures (Kelvin ), so, if we are working with relative temperatures such as Celsius degrees or Fahrenheit degrees, we need to convert the temperatures to Kelvin.

We can convert from Celsius degrees to Kelvin using the following formula:

[tex]Temperature(K)=Temperature(C\°)+273[/tex]

So, we have the Gay-Lussac's equation:

[tex]\frac{P_{1}}{T_{1}}=\frac{P_{2}}{T_{2}}[/tex]

Also, we are given the following information:

[tex]T_{1}=30\° \\P_{1}=2atm\\T_{2}=40\°[/tex]

Therefore, converting the temperature to Kelvin, we have:

[tex]T_{1}=30C\°=30+273K=303K\\\\T_{1}=40C\°=40+273K=313K\\[/tex]

Now, calculating we have:

[tex]\frac{P_{1}}{T_{1}}=\frac{P_{2}}{T_{2}}[/tex]

[tex]P_{2}=\frac{P_{1}}{T_{1}}*T_{2}\\\\P_{2}=\frac{2atm}{303K}*313K=2.07atm[/tex]

Hence, the new pressure will be 2.07 atm.

[tex]P_{2}=2.07atm[/tex]

Have a nice day!

Answer:

6.55 atm

Explanation:

we can use the ideal gas law equation to find the pressure of the container

PV = nRT

where P - pressure

V - volume

n - number of H₂ moles - 1.09 g  / 2 g/mol = 0.545 mol

R - universal gas constant - 0.08206 L.atm/mol.K

T - temperature in kelvin - 20 °C + 273 = 293 K

substituting the values in the equation

P x 2.00 L = 0.545 mol x 0.08206 L.atm/mol.K x 293 K

P = 6.55 atm

pressure in the container is 6.55 atm

Answer:

[tex]\boxed{\text{11.7 g}}[/tex]

Explanation:

We are given the amounts of two reactant solutions, so this is a limiting reactant problem.

We know that we will need a balanced equation with masses, moles, and molar masses, so, let's assemble our information in one place, with molar masses above the formulas and the

M_r:                                                                              234.77

                      2AgNO₃          +           CaI₂               ⟶ 2AgI + Ca(NO₃)₂

Solution: (50.00 mL, 1.00 M)    (30.00 mL, 1.25 M)

Step 1.  Calculate the moles of each reactant  

Moles of AgNO₃ = 50.00 mL × (1.00 mmol/1 mL)  = 50.00 mmol

    Moles of CaI₂ = 30.00 mL × (1.25 mmol/1 mL)  = 37.50 mmol

Step 2. Identify the limiting reactant  

Calculate the moles of AgI we can obtain from each reactant.

From AgNO₃:  

The molar ratio of AgI:AgNO₃ is 2:2.

Moles of AgI  = 50.00 mmol AgNO₃ × (2 mmol AgI/2 mmol AgNO₃)

= 50.00 mmol AgI  

From CaI₂:

The molar ratio of AgI:CaI₂ is 2:1.  

Moles of CaI₂ = 37.50 mmol × (2 mmol AgI/1 mmol CaI₂) = 75.00 mmol AgI  

AgNO₃ is the limiting reactant because it gives the smaller amount of AgI.  

Step 3. Calculate the mass of AgI.

Mass = 50.00 mmol AgI × (234.77 mg AgI /1 mmol AgI)

= 11 700 mg AgI = 11.7 g AgI

The mass of silver iodide formed is [tex]\boxed{\textbf{11.7 g}}[/tex].

        If people are to drive less it only means fewer carbon dioxide emissions because people will save on gasoline. Similarly, it helps keep around 20 pounds of carbon dioxide out of this atmosphere thus reducing the amount of greenhouse gases. Clearly, car related emissions are the major cause of global warming.

        Change a light. Replacing one regular light bulb with a compact fluorescent light bulb will save 150 pounds of carbon dioxide a year.

        Recycling helps reduce greenhouse gas emissions by reducing energy consumption. Using recycled materials to make new products reduces the need for virgin materials. This avoids greenhouse gas emissions that would result from extracting or mining virgin materials.

Answer:

The oxygen-rich blood is then pumped out to your body through your arteries. It's bright red at this point. ... Your lips have a lot of these capillaries, which is why they're red. Your blood, now exhausted of its oxygen, is dark red as it now returns to your heart through your veins.

Explanation:

Answer:

The bright red blood leaving your heart is that color because it has more oxygen. The blood loses some oxygen and turns darker red before it returns to your heart.

Explanation:

A characteristic of scientific theory is that it summarizes a set of observations. It is not a mere guess or hypothesis but a widely accepted explanation, which may change as new evidence or perspectives emerge.

One characteristic of a scientific theory is that it summarizes a set of observations. A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method, and it is repeatedly tested and confirmed through observation and experimentation. While a scientific theory can be modified or disproven based on new evidence or perspectives, it is not merely a guess or a hypothesis, but a widely accepted model or framework for understanding certain phenomena.

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Answer:

C. No shift as the reaction is in equilibrium

Explanation:

Q (the reaction quotient) and K (the equilibrium constant are equal) which means it's in equilibrium.

Answer:

= 3132.9 Joules

Explanation:

In this case;

Kinetic energy = 0.5 × 0.018 kg × 590²

                        = 3132.9 Joules

Answer: In polar covalent bonds a pair of electrons are unequally shared between two atoms, while in nonpolar covalent bonds two atoms share a pair of electrons with each other.

I hope this helps :)

Explanation:

Answer:

572 g

Explanation:

Molar mass is the mass of 1 mol of an element or compound

molar mass of Li₂SO₄ is the sum of the products of the molar masses of the elements by the number of atoms in the compound

molar masses of each element making up lithium sulphate

Li - 7 g/mol

S - 32 g/mol

O - 16 g/mol

molar mass of Li₂SO₄ - (7 g/mol x 2) + ( 32 g/mol x 1) + ( 16 g/mol x 4 )

molar mass = 110 g/mol

mass of 1 mol of Li₂SO₄ is 110 g

therefore mass of 5.2 mol of Li₂SO₄ is - 110 g/mol x 5.2 mol = 572 g

mass is 572 g

I think the answer is #1.

For starters, if a species goes extinct, their predators would go down since their source of food is now gone.

Also, habitat loss accounts for the biggest reason animals are becoming extinct

A. Cesium is your answer

Answer:

Cesium

Explanation:

The atomic radius is the distance between the nucleus and the outermost orbital of an atom. By the atomic radius, it is possible to determine the size of the atom.

The atomic radius is a periodic trend that means that it is a specific pattern in the properties of the chemical elements that are revealed in the periodic table

This property increases as follows (see attached file)

Therefore the element that is lower in the group is the one with the largest radius

In this case, the one located below in the group is cesium, that is, the one with the largest radius

Answer:

The correct answers are first, fourth, fifth

Explanation:

The characteristics that Jupiter and Saturn share include the following:

It should be noted that Jupiter and Saturn are known to be the two largest planets. They are also composed of two main elements which are helium and hydrogen.

Also, Saturn has 8 rings while Jupiter has 4 rings. Saturn and Jupiter are mostly made of gases and have thick atmospheres.

In conclusion, the correct options are 1, 4, and 5.

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Answer:Soil source

Explanation:

Answer:

soil source

Explanation:

Answer:

1. 2.8 moles of H₂

2. 7.38 moles of CO₂

3. 5.3 moles of O₂

4. 7.4 moles of KNO₃

Explanation:

Here are the steps to doing this:

1. Write the chemical equation of each reaction.

2. Balance the equation.

3. Find out the ratio between reactant and product

4. Determine the actual yield of your reactants.

5. The amount of product produced is determined by how much product the limiting reactant produces.

Let's do this!

1. Given: 3.4 moles of Magnesium(Mg) and 5.6 moles of Hydrochloric acid (HCl)

Equation:

Mg + 2HCl → MgCl₂ + H₂

Reactant to Product ratio

1 mole of Mg produces 1 mole of H₂      [tex]\dfrac{1moleof Mg}{1mole of H_{2}}[/tex]

2 moles of HCl produces 1 mole of H₂  [tex]\dfrac{2molesofHCl}{1mole of H_{2}}[/tex]

Determine actual yield of reactants

[tex]3.4moles of Mg\times\dfrac{1moleofH_2}{1moleofMg}=3.4molesofH_{2}\\\\5.6moles ofHCl\times\dfrac{1moleofH_2}{2moleofHCl}=2.8molesofH_{2}[/tex]

Since 5.6 moles of HCl can only produce 2.8 moles of H₂, before it is used up, then this means that that is all the product this reaction can produce.

2. Given: 3.4 moles of C₃H₈ and 12.3 moles of oxygen gas (O₂)

Equation:

C₃H₈  +  5O₂ → 3CO₂ + 4H₂O

Reactant to Product ratio

1 mole of C₃H₈ produces 3 moles of CO₂      [tex]\dfrac{1moleofC_{3}H_{8}}{3molesofCO_{2}}[/tex]

5 moles of O₂ produces 3 moles of CO₂       [tex]\dfrac{5molesofO_{2}}{3moleofCO_{2}}[/tex]

Determine actual yield of reactants

[tex]3.4molesofC_{3}H_{8}\times\dfrac{3molesofCO_{2}}{1moleofC_{3}H_{8}}=10.2molesofH_{2}[/tex]

[tex]12.3molesofO_{2}\times\dfrac{3molesofCO_{2}}{5molesofO_{2}}=7.38molesofCO_{2}[/tex]

The answer is then 7.38 moles of CO₂

**3. 5.3 moles of H₂O

This one is a little bit different. It is asking how much of a reactant is needed to produce the amount of product given. For this, just write a balanced equation for the reaction and get the ratio of reactant to product and solve for the actual yield. Since it is only asking for oxygen gas, you just need to do that one.

Equation:

CH₄  + 2O₂ → CO₂ + 2H₂O

Reactant to Product ratio

[tex]\dfrac{2molesofO_{2}}{2molesofH_{2}O}=\[tex]7.88molesofKI\times\dfrac{1moleofKNO_{3}}{1moleofKI}=7.88molesofKNO_{3}[/tex]

Actual yield:

[tex]5.3molesofH_{2}O\times\dfrac{1moleofO_{2}}{1moleofH_{2}O}=5.3molesofO_{2}[/tex]

The answer is 5.3 moles of O₂.

4. 3.7 moles of Lead (II) Nitrate (Pb(NO₃)₂) and 7.8 moles of Potassium Iodide (KI)

Equation:

Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃

Reactant to Product ratio

[tex]\dfrac{2molesofKI}{2molesofKNO_{3}}=\dfrac{1moleofKI}{1moleofKNO_{3}}[/tex]

[tex]\dfrac{1molesofPb(NO_{3})_{2}}{2molesofKNO_{3}}[/tex]

Actual yield:

[tex]3.7molesofPb(NO_{3})_{2}\times\dfrac{2molesofKNO_{3}}{1moleofPb(NO_{3})_{2}}=7.4molesofKNO_{3}[/tex]

The answer is 7.4 moles of KNO₃.

Final answer:

An ice cube has less heat energy than a cup of hot tea because the particles in the ice cube have lower kinetic energy than those in hot tea. The term 'cold energy' is not scientifically accurate; heat energy transfer is the correct concept. The correct answer is A) less heat energy.

Explanation:

An ice cube has less heat energy than a cup of hot tea. This statement aligns with the behavior of heat energy where the particles of a colder substance, like an ice cube, move much slower and thus have lesser kinetic energy compared to the particles in a warmer substance, such as hot tea. Therefore, the correct answer is A) less heat energy. The concept of 'cold energy' is not a scientific term in physics; instead, we discuss energy transfer in terms of heat. For instance, when an ice cube melts, it absorbs heat energy from its surroundings. Hence, a cup of hot tea has more heat energy, which is why it can transfer energy to the ice cube causing it to melt.