help please it’d be greatly appreciated lol

Answer:

The sharklet film creates a phenomenon reffed to as  mechanotransduction.

Explanation:

It was discovered that sharks do not experience fouling , their skin is made in a distinct manner with diamond patterns that will discourage micro organism from settling on it.

Through the process of mechanotransduction, mechanical stress is created to the bacteria whereby they cannot attach themselves to the surface because it makes them to produce more energy to settle on the surface thus they may keep off from the surface. In this manner, bacteria is inhibited from attacking these areas protected by the sharklet film.

Answer:

C. Protons and neutrons. They are located in the nucleus f an atom while the electrons orbit the nucleus.

Hey there! :D

This is a true statement. Gamma radiation comes from electromagnetic energy from radioactive decay. This decay has the shortest electromagnetic wave lengths and therefore has the highest photon energy. It is extremely dangerous. Radiation in general is something to be cautious of!

I hope this helps!

~kaikers

Answer:

0.4167 J/°C.g.

Explanation:

Q = m.c.ΔT,

where, Q is the amount of heat absorbed by substance (Q = 2500 J).

m is the mass of the substance (m = 100 g).

c is the specific heat of the substance (c = ??? J/°C.g).

ΔT is the difference between the initial and final temperature (ΔT = final T - initial T = 70°C - 10°C = 60°C).

∵ Q = m.c.ΔT

∴ c = Q/(m.ΔT) = (2500 J)/(100 g)(60°C) = 0.4167 J/°C.g.

The study of the chemical and bond is called chemistry. According to the law of thermodynamics, the heat transfer from the high temperature to the low temperature.

The correct answer to the question is 0.4167.

To solve this problem, we can use the relation:

Q = m.c.ΔT,

where,

Q = m.c.T

After the equation, we can get.

c = [tex]\frac{Q}{(m.T)} = \frac{(2500 J)}{(100 g)(60C)}\\ \\ = 0.4167[/tex]

Hence, the correct answer is 0.4167.

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Answer:

Butanoic acid

Explanation:

cooh-carboxyl functuonal group

In  'Ch3ch2ch2cooh​'       there are 4 carbons.

That means the name of the compound will start with But

There is also a COOH, which means that the compound is a carboxylic acid. So the compound will end in anoic  acid.

Add these two together and you get:  Butanoic acid

(But + anoic acid = Butanoic acid)  

---------------------------------------------

Answer

Butanoic acid

Answer:

131.7 grams of carbon dioxide would be formed

Explanation:

2C₂H₂ + 5O₂ = 4CO₂ + 2H₂O

m(CO₂)/{4M(CO₂)} = m(C₂H₂)/{2M(C₂H₂)}

m(CO₂)=2M(CO₂)m(C₂H₂)/M(C₂H₂)

m(CO₂)=2*44g/mol*38.9g/26g/mol = 131.7 g

131.7 grams of carbon dioxide would be formed

Answer: The mass of carbon dioxide produced in the given reaction is 132 grams.

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]      .....(1)

Given mass of ethyne = 38.9 g

Molar mass of ethyne = 26 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of ethyne}=\frac{38.9g}{26g/mol}=1.5mol[/tex]

[tex]2C_2H_2+5O_2\rightarrow 4CO_2+2H_2O[/tex]

By Stoichiometry of the reaction:

2 moles of ethyne produces 4 moles of carbon dioxide.

So, 1.5 moles of ethyne will produce = [tex]\frac{4}{2}\times 1.5=3mol[/tex] of carbon dioxide.

Molar mass of carbon dioxide = 44 g/mol

Moles of carbon dioxide = 3 moles

Putting values in equation 1, we get:

[tex]3mol=\frac{\text{Mass of carbon dioxide}}{44g/mol}\\\\\text{Mass of carbon dioxide}=132g[/tex]

Hence, the mass of carbon dioxide produced in the given reaction is 132 grams.

E is the correct answer because both endothermic and exothermic reactions require activation energy. the reactants have less potential energy than do the products. Energy must be input in order to raise the particles up to the higher energy level.

Answer:

C. Forming the activated complex requires energy,

Explanation:

For any reaction (whether exothermic or endothermic) the reactant molecules need some minimum amount of energy known as Threshold energy.

Reactant molecules have some internal energy and they require some extra amount of energy to reach the threshold energy which is known as activation energy.

This activation energy is required to from an activated complex.

The activated complex is formed where reactant molecules come closer to each other and undergo effective collision. This causes the formation of products.

Answer:

Explanation:

Hydrogen is a nonmetallic, colorless gas under ordinary conditions. It becomes an alkali metal under extreme pressure.

Atomic Number: 1

Symbol: H

Atomic Mass: 1.008

Electron Configuration: 1s1

Group: group 1, s-block, nonmetal

Helium is a light, colorless gas that forms a colorless liquid.

Atomic Number: 2

Symbol: He

Atomic Mass: 4.002602(2)

Electron Configuration: 1s2

Group: group 18, s-block, noble gas

Lithium is a reactive silver metal.

Atomic Number: 3

Symbol: Li

Atomic Mass: 6.94 (6.938–6.997)

Electron Configuration: [He] 2s1

Group: group 1, s-block, alkali metal

Beryllium is a shiny gray-white metal.

Atomic Number: 4

Symbol: Be

Atomic Mass: 9.0121831(5)

Electron Configuration: [He] 2s2

Group: group 2, s-block, alkaline earth metal

Boron is a gray solid with a metallic luster.

Atomic Number: 5

Symbol: B

Atomic Mass: 10.81 (10.806–10.821)

Electron Configuration: [He] 2s2 2p1

Group: group 13, p-block, metalloid

Carbon takes several forms. It's usually a gray or black solid, although diamonds may be colorless.

Atomic Number: 6

Symbol: C

Atomic Mass: 12.011 (12.0096–12.0116)

Electron Configuration: [He] 2s2 2p2

Group: group 14, p-block, usually a nonmetal although sometimes considered a metalloid

Nitrogen is a colorless gas under ordinary conditions. It cools to form a colorless liquid and solid forms.

Atomic Number: 7

Symbol: N

Atomic Mass: 14.007

Electron Configuration: [He] 2s​2 2p3

Group: group 15 (pnictogens), p-block, nonmetal

Oxygen is a colorless gas. Its liquid is blue. Solid oxygen may be any of several colors, including red, black, and metallic.

Atomic Number: 8

Symbol: O

Atomic Mass: 15.999 or 16.00

Electron Configuration: [He] 2s2 2p4

Group: group 16 (chalcogens), p-block, nonmetal

Fluorine is a pale yellow gas and liquid and bright yellow solid. The solid may be either opaque or translucent.

Atomic Number: 9

Symbol: F

Atomic Mass: 18.998403163(6)

Electron Configuration: [He] 2s2 2p5

Group: group 17, p-block, halogen

Neon is a colorless gas that emits a characteristic orange-red glow when excited in an electric field.

Atomic Number: 10

Symbol: Ne

Atomic Mass: 20.1797(6)

Electron Configuration: [He] 2s2 2p6

Group: group 18, p-block, noble gas

Sodium is a soft, silvery-white metal.

Atomic Number: 11

Symbol: Na

Atomic Mass: 22.98976928(2)

Electron Configuration: [Ne] 3s1

Group: group 1, s-block, alkali metal

Magnesium is a shiny gray metal.

Atomic Number: 12

Symbol: Mg

Atomic Mass: 24.305

Electron Configuration: [Ne] 3s2

Group: group 2, s-block, alkaline earth metal

Aluminum is a soft, silver-colored, nonmagnetic metal.

Atomic Number: 13

Symbol: Al

Atomic Mass: 26.9815385(7)

Electron Configuration: [Ne] 3s2 3p1

Group: group 13, p-block, considered a post-transition metal or sometimes a metalloid

Silicon is a hard, blue-gray crystalline solid that has a metallic luster.

Atomic Number: 14

Symbol: Si

Atomic Mass: 28.085

Electron Configuration: [Ne] 3s2 3p2

Group: group 14 (carbon group), p-block, metalloid

Phosphorus is a solid under ordinary conditions, but it takes several forms. The most common are white phosphorus and red phosphorus.

Atomic Number: 15

Symbol: P

Atomic Mass: 30.973761998(5)

Electron Configuration: [Ne] 3s2 3p3

Group: group 15 (pnictogens), p-block, usually considered a nonmetal, but sometimes a metalloid

Sulfur is a yellow solid.

Atomic Number: 16

Symbol: S

Atomic Mass: 32.06

Electron Configuration: [Ne] 3s2 3p4

Group: group 16 (chalcogens), p-block, nonmetal

Chlorine is a pale yellow-green gas under ordinary conditions. Its liquid form is bright yellow.

Atomic Number: 17

Symbol: Cl

Atomic Mass: 35.45

Electron Configuration: [Ne] 3s2 3p5

Group: group 17, p-block, halogen

Argon is a colorless gas, liquid, and solid. It emits a bright lilac-purple glow when excited in an electric field.

Atomic Number: 18

Symbol: Ar

Atomic Mass: 39.948(1)

Electron Configuration: [Ne] 3s2 3p6

Group: group 18, p-block, noble gas

Potassium is a reactive, silvery metal.

Atomic Number: 19

Symbol: K

Atomic Mass: 39.0983(1)

Electron Configuration: [Ar] 4s1

Group: group 1, s-block, alkali metal

Calcium is a dull silver metal with a faint yellowish cast.

Atomic Number: 20

Symbol: Ca

Atomic Mass: 40.078(4)

Electron Configuration: [Ar] 4s2

Group: group 2, s-block, alkaline earth metal

Hope That Helps!

Brainliest?

(the other person copied it from Google).

Answer:

Independent variable: Colour of the container

Dependent variables: The water amount and the room temperature

3 Constants: Amount of water, location of the containers and the container size.

Hypothesis: I think that the black container will heat up the water the fastest, as the colour black absorbs heat.

Hope it helps! :)

Answer:

= 5.193 g

Explanation:

Half life is the time taken by a radioactive element to decay by half its original amount. Therefore, since half life of carbon-14 is 5700 years, then it would take 5700 years for a sample of carbon-14 to decay by half of its original amount.

Using the formula;

New mass = Original mass × (1/2)^n, where n is the number of half lives.

n = Period taken/Half life = 6350 years/5700 years =1.114

Therefore;

New mass = 11.24 × (1/2)^1.114

                 = 5.193 g

Hence, a mass of 5.193 g of Carbon-14 would remain after 6350 years.

After one half-life of 5700 years, half of the initial amount carbon-14 in the organism would remain, which is 5.62g. The time period of 6350 years is more than one half-life so we know the amount of carbon-14 left will be less than 5.62g.

The question requires us to calculate how much carbon-14 will remain in an organism after 6350 years, given that it had 11.24g at the time of its death and the half-life of carbon-14 is 5700 years. This is a question of radioactive decay and can be solved using the concept of half-lives. Knowing the half-life of a radioactive isotope means knowing how long it typically takes for half of that isotope to decay.

After one half-life (5700 years), half of the initial carbon-14 in the organism would remain, so after that time, the organism would have 11.24g / 2 = 5.62g of carbon-14 left. The requested time period of 6350 years is more than one half-life but less than two. As radioactive decay is a random process, we can't say exactly how much will remain at this time, but we know it will be less than 5.62g and more than half of that again.

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Answer : A light year is approximately 9.5 trillion kilometers - A)

Answer:

the answer is A) 9.5 trillion kilometers

Explanation:i got you ny g m

Answer:A star topology is designed with each node (like workstations, printers, laptops, servers etc.) connected directly to a central device called as a network switch. Each workstation has a cable that goes from its network card to a network switch.

Most popular and widely used LAN technology Ethernet currently operates in Star Topology.

Explanation:

Answer:

A. Metalloid

E. Has similar properties as Ge

F. Belongs to Period 3​

Explanation:

Silicon is the 14th element on the periodic table. Its unit is SI. Its properties straddles between those of metals and non-metals and it is described as a non-metal.

It's atomic weight or mass number is 28u. It has an atomic number of 14 i.e in its neutral state, the number of protons and electrons are equal to 14.

Silicon belongs to the 4th group and the 3rd period on the periodic table. Elements in the same group share similar chemical properties. The elements in Si group are: C, Ge, Sn and Pb. The properties of Si is similar to these elements because they all have a valency of 4. Across the period, the properties varies this is why Si would have a very different property from Al and P.

Answer:

The answer is location B

Explanation:

All spinal cord levels have a dorsal horn, which is made up of sensory nuclei that take in and interpret incoming somatosensory information. Ascending projections arise from there and carry the sensory data to the diencephalon and midbrain.

A column of nerve fibers that extends from the skull base to the middle of the back. It has three thin membrane-like layers of protecting tissue covering it. The vertebrae encircle the spinal cord and its surrounding membranes.

At least some of the neurons in the superficial dorsal horn continue to be selective for the modalities represented by the primary afferent ends.

The dorsal horn, one of the spinal cord's divisions of grey matter, houses neurons that enter ascending sensory pathways as well as interneurons that link to other spinal cord cells. The substantial gelatinosa is present.

Thus, The initial relay for afferent impulses from the body's skin, muscles, and viscera is located in the dorsal horn of the spinal cord.

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Answer:

[tex]\boxed{\text{57.7 g} }[/tex]

Explanation:

The first step is to calculate the molar mass of H₂O:

[tex]\begin{array}{rcr}\text{2 H} & = & 2.02\\\text{1 O} & = & 16.00\\\text{TOTAL} & = & \mathbf{18.02}\\\end{array}[/tex]

So, 1 mol has a mass of 18.02 g.

Next you calculate the mass of 3.2 mol of H₂O

[tex]\begin{array}{rcl}m & = & \text{3.2 mol H$_{2}$O} \times \dfrac{\text{18.02 g H$_{2}$O}}{\text{1 mol H$_{2}$O}}\\ & = &\boxed{\textbf{57.7 g H$_{2}$O}} \\\end{array}[/tex]

The mass of 3.2 moles of H₂O is calculated by multiplying the number of moles by the molar mass of water, which is 18.015 g/mol, giving a total mass of 57.648 grams.

The mass of 3.2 moles of H₂O can be calculated using its molar mass. The molar mass of water (H₂O) is 18.015 g/mol, calculated by summing the molar masses of each atom in the molecule: (1.0079 + 1.0079 + 15.999).

To find the mass, simply multiply the number of moles by the molar mass:

Mass = Moles × Molar Mass

Mass = 3.2 moles × 18.015 g/mol = 57.648 g

This result gives you the mass of water for the given moles.

Answer:

x=4 or B

Explanation:

It says that the increase in temperature is (2x+1) and that is within (x+5) seconds. Therefore, (2x+1)/(x+5)=(x-3). X then equals 4, or -4. Therefore, the answer is 4, or B.

A possible value of x = B)4

The main composition of algebraic expressions are:

algebraic forms separated by arithmetic operations

consists of one phrase (monomial) to many phrases (polynomial)

is a value that can be changed, can be in the form of letters, for example, x, y, a, b, etc.

is a fixed value, can be a number

+, -,:, x

The Average Rate of Change of a function shows the comparison between 2 objects that change

If we use the notation function, the Average rate of Change of a function from a to b can be formulated as:

[tex] \large {\boxed {\boxed {\bold {ROC = \frac {f (a) -f (b)} {a-b}}}} [/tex]

ROC = rate of change

a temperature increases by (2x + 1) ºC from the original x, in x + 5 seconds, then the average rate of change is (x - 3) C / s.

There are 2 functions that change, temperature and time

If we change above statement to algebraic form, it becomes

[tex]\rm ROC=\dfrac{\Delta temperature}{\Delta time}\\\\x-3=\dfrac{2x+1}{x+5}\\\\(x-3)(x+5)=2x+1\\\\x^2+2x-15=2x+1\Rightarrow combine\:like\:terms\\\\x^2+2x-2x-15-1=0\\\\x^2-16=0\\\\(x+4)(x-4)=0\\\\x=4,x=-4\Rightarrow use\:positive\:value\:x=4[/tex]

6 squared divided by 2 (3) +4  

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an algebraic expression  

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Answer:

B) compound

A chemical formula is a compound of different chemicals.

Final answer:

A substance with a chemical formula is typically a compound since it is made up of two or more elements in a fixed ratio. An organic compound, in the case of containing covalently-bonded carbon and hydrogen, differs from an atom which is the simplest indivisible chemical substance.

Explanation:

Given a chemical formula, a substance is most likely classified as a compound. Compounds are substances that result from the combination of two or more elements in a fixed ratio. For example, water (H₂O) is a compound composed of two elements, hydrogen and oxygen, combined in a constant ratio. Here is a step-by-step approach to classifying a substance:

Identify the molecule by the provided chemical formula.

Write the molecular formula.

Determine if the molecule is a covalent, ionic or metallic substance based on the types of bonds present.

In the body, any substance that contains covalently-bonded carbon and hydrogen is classified as an organic compound. The term 'atom' applies to the simplest chemical substances that cannot be broken down chemically into a simpler substance. Therefore, the correct answer to the question is that based on the chemical formula, the substance is most likely a compound.

Answer:

0.0250 g.

Explanation:

∵ no. of moles (n) = mass / molar mass.

∴ mass of Vitamine C = (n)(molar mass) = (0.000142 mol)(176.12 g/mol) = 0.02501 g = 0.0250 g. "three significant figures"

Answer:

Chlorine and bromine

Explanation: The chlorine and bromine acts as reactive gases and destroy the ozone  present in the stratospheric ozone.

The ozone layer is present in the stratosphere to filter the harmful rays of the sun that is harmful for the people living on earth.

A chlorine or bromine molecule can destroy thousand of the ozone molecules before it leaves the stratosphere.

So, a single bromine or chlorine atom can affect the ozone layer.

Bromine and chlorine are major contributors to ozone layer destruction. The correct answer is bromine and chlorine.

The ozone layer, which is located in the stratosphere, plays a crucial role in protecting life on Earth by absorbing harmful ultraviolet (UV) radiation from the sun.

Certain chemicals have been identified as major contributors to the depletion of this layer.

These chemicals contain halogens, specifically chlorine and bromine, which are highly reactive and can destroy ozone molecules through a series of catalytic reactions.

Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are the primary sources of chlorine in the stratosphere.

When these compounds reach the stratosphere, they are broken down by UV radiation, releasing chlorine atoms.

Each chlorine atom can destroy thousands of ozone molecules in a catalytic cycle that does not consume the chlorine atom, allowing it to continue depleting ozone.

Similarly, halons, which contain bromine, are another group of chemicals that contribute significantly to ozone depletion.

Bromine is even more efficient at destroying ozone than chlorine, making halons particularly harmful to the ozone layer.

Phosphorus, nitrogen, carbon dioxide, and methane are not directly involved in the catalytic destruction of ozone in the same way as chlorine and bromine.

While nitrogen oxides (NOx) can participate in ozone destruction cycles, they are not considered major contributors compared to chlorine and bromine from CFCs, HCFCs, and halons.

Carbon dioxide and methane are greenhouse gases that contribute to global warming and climate change, but they do not directly destroy ozone molecules in the stratosphere.

Therefore, the two chemicals that are major contributors to ozone layer destruction are chlorine and bromine.

Answer:

According to Le Chatelier's Principle, low temperature and high pressure are the condition that will produce the highest yield of ammonia.

Explanation:

The Haber process is a reaction that combines nitrogen with hydrogen to form ammonia according to the following balanced equation:

Equilibrium considerations for Temperature changes:

You need to shift the equilibrium position  as far as possible favoring the forward reaction (reaction to the right) in order to obtain the highest yield of ammonia in the equilibrium mixture.  the reaction is exothermic and can be expressed as following:

If the temperature is increased, the heat content of the system will increase, so the system would consume some of that heat by shifting the equilibrium to the left, thereby producing less ammonia.

According to Le Chatelier's Principle, the forward reaction will be favored if you lower the temperature you will get more ammonia (i.e. highest yield). The system will respond by moving the position of equilibrium to counteract this - in other words by producing more heat.

Equilibrium considerations for Pressure changes:

for the Haber process reaction

One can note that there are 4 moles on the left-hand side of the equation, but only 2 on the right.

According to Le Chatelier's Principle, if you increase the pressure the system will respond by favoring the reaction which produces fewer no. of  moles. That will cause the pressure to fall again.

In order to get as much ammonia as possible in the equilibrium mixture, you need as high a pressure as possible producing more ammonia (i.e. highest yield)..

Answer:    A chemical process must occur and then changes between the state of the reactants and the state of the products can be determined

Explanation:  Enthalpy represents the sum of the energy of the system with the product of the pressure and volume of that system. As a thermodynamic property, it expresses the ability to release heat from the system. In fact, enthalpy  tells us how much heat and work has changed during the chemical reaction under constant pressure. When measuring, measurements of the difference in enthalpy between the two states of the system is performed, before and after the chemical reaction, since total enthalpy can not be measured. This measurement of the enthalpy change can tell us, for example, whether the heat was released from the system during the reaction, or the system absorbed the heat.

Answer:

B.

Explanation:

Answer:

Explanation:

The properties of covalent bonds are:

1. Low boiling points and melting points.

2. Various colors.

3. Poor conductors of heat and electricity.

4. Brittle solids.

Covalent compounds form through the combination of two non-metals that share electrons. These compounds have low melting and boiling points and do not conduct electricity due to lack of free ions.

A property of covalent compounds is that they are typically formed when two non-metals combine, resulting in the sharing of electrons between atoms. This shared electron pair is known as a covalent bond. Another important property is that covalent compounds have low melting and boiling points compared to ionic compounds because they do not have charged ions, so the forces between molecules are weaker. Covalent compounds also don't conduct electricity as there aren't many free ions to carry charge.

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Answer:

3.0 x 10⁻⁴ moles

Explanation:

Given parameters:

Amount of Ag atoms = 1.8 x 10²⁰ atoms

Unknown:

Number of moles of Ag atoms

Solution:

From mole concept, we know that a mole of a substance contains Avogadros number of particles.

The Avogadro's number of particles is 6.02 x 10²³.

Now:

Number of moles

= number of particles/6.02 x 10²³

Therefore:

Number of moles= 1.8 x 10²⁰ / 6.02 x 10²³

Number of moles = 0.3 x 10⁻³ moles

= 3.0 x 10⁻⁴ moles

Taking into account the definition of avogadro's number, the correct answer is option A. 3×10⁻⁴ moles of silver are 1.8×10²⁰ atoms of silver.

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023×10²³ particles per mole. Avogadro's number applies to any substance.

Then you can apply the following rule of three: if 6.023×10²³ atoms are contained in 1 mole of silver, then 1.8×10²⁰ atoms are contained in how many moles of silver?

amount of moles of silver= (1.8×10²⁰ atoms × 1 mole)÷ 6.023×10²³ atoms

amount of moles of silver≅ 3×10⁻⁴ moles

Finally, the correct answer is option A. 3×10⁻⁴ moles of silver are 1.8×10²⁰ atoms of silver.

Learn more about Avogadro's Number:

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13.5 Moles Kcl x 6.022 x 10^23 /1

= 8.12 x 10^24

whenever you need to find molecules just multiply moles by avogadro number

Answer:

it's c

Explanation:

The fission reaction is uranium-235 absorbing a neutron and splitting into barium-141, krypton-92, and three neutrons. Therefore, option C is correct.

When a neutron collides with a larger atom, it causes it to excite and split into two smaller atoms, which are known as fission products. Additional neutrons are released, which can set off a chain reaction. A tremendous amount of energy is released when each atom splits.

The splitting of uranium-235 or plutonium-239 to release a large amount of energy. A lot of energy, two smaller atoms, and three neutrons.

Thus, The fission reaction is uranium-235 absorbing a neutron and splitting into barium-141, krypton-92, and three neutrons, option C is correct.

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Search it up pppppp pp pp

The reaction 4NO(g) → 2N2(g) + 2O2(g) is exothermic because the reverse process consumes energy.

The chemical reaction 4NO(g) → 2N2(g) + 2O2(g) is being asked if it is endothermic or exothermic. Based on the information provided, we can infer that the reverse process, forming 2NO(g) from N2(g) and O2(g), requires the input of 181 kJ of energy. Therefore, the reaction where 4NO(g) decomposes into 2N2(g) and 2O2(g) would release that energy, indicating that the reaction is exothermic.

This is supported by similar reactions listed, such as N2(g) + O2(g) + 45 kcal → 2NO(g) and N2O2(g) → 2 NO2(g), which are both endothermic requiring heat; hence their reverse reactions would be exothermic as they release heat

The planets, in order from largest to smallest diameter, are ordered as follows in the options given: Saturn, Uranus, Earth. Therefore, the correct answer is D.

The correct order of planets, from largest to smallest based on diameter, is reflected in answer option D: Saturn, Uranus, Earth. Saturn is the second largest planet, Uranus is the third largest, and Earth is the fifth largest ignoring the four smallest planets which are Neptune, Mars, Venus, and Mercury. Therefore, according to the given options, D is the most accurate listing of planets from largest to smallest based on diameter.

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Answer:

[tex]\boxed{\text{(2) A mixture can be separated by physical means.}}[/tex]

Explanation:

For example, you can separate a mixture of sand and water by pouring it through a coffee filter.

(1) is wrong. A mixture must have at least two components.

(3) is wrong. A mixture can have a any composition depending on the amount of each component.

(4) is wrong. A mixture of sand and water is heterogeneous,

answer is #2 : a mixture can be separated by physical means

Answer:

Solar eclipse

Explanation:

Answer:

11 km/hr

Explanation:

Taking Alana as the reference frame, we consider the speed with which the ball gets away from her. Therefore the speed given will be with respect to Alana. In this case we disregard the 19 km/hr as it is common to both Alana and the ball.

Answer:

Speed, v = 30 km/h

Explanation:

It is given that,

Speed while skateboarding, v₁ = 19 km/h

Speed with which tennis ball is thrown, v₂ = 11 km/h

We have to find the speed of the tennis ball from the Alana's frame of reference.

v = v₁ +v₂

v = 19 km/h + 11 km/h

v = 30 km/h

Hence, this is the required solution.