Why does a comet make a bright trail in the night sky?

1.A comet is made of ice, dust and gas that vaporize as the comet moves closer to the sun, leaving a trail.

2. A comet is made of ice, dust and gas that vaporize as the comet moves closer to the sun, leaving a trail.

3. A comet gives off light because of the mineral composition of the rocks from which the comet is formed.

4. A comet produces an optical illusion of a bright trail due to the layers of Earth’s atmosphere.

5. A comet is made of rock, which burns and lights up as the comet moves faster in the atmosphere.

Explanation:

Elements on the periodic table are arranged with increasing number of atomic number based on their periodic properties.

Metals lose electrons to form cations that is why they have an increse in atomic number. For metalliods, they possess both metal and non- metal characters and that is why they happen to be in two separate rows at the bottom of the table.

Answer:

0.1098 M

Explanation:

Answer:

pH = 4.45

Explanation:

We need to find the pH of \(3.5\times 10^{-5}\ M\) solution of HCl. We know that, pH of a solution is given by :

\(pH=-log[H]^+\)

Put all the values,

\(pH=-log[3.5\times 10^{-5}]\\\\pH=4.45\)

So, the pH of the solution of HCl is 4.45.

Over-tilling and Over farming are the two processes that can harm the fertility of the soil.

Over-tilling refers to the exceeding levels of tilling and levelling the soil which adversely affects the quality of the soil. This is because tillage fractures the soil, it disrupts soil structure, accelerating surface runoff and soil erosion. Tilling of soil also reduces crop residue, which help cushion the force of pounding raindrops.

Without crop residue, soil particles become more easily dislodged, being moved or 'splashed' away. The splashed particles clog soil pores, effectively sealing off the soil's surface, resulting in poor water infiltration and hence subsequently affects the soil fertility.

Similarly, the main effect of over-farming is soil depletion. When crops are grown in the same place year after year, the soil becomes depleted of the nutrients that the plants need to grow. This can lead to lower yields and poorer quality crops. In extreme cases, it can lead to desertification.

So, these two are the processes that can harm soil fertility.

To know more about soil erosion, click below:

https://brainly.com/question/17905503

#SPJ9

Answer:

56.88g N2

Explanation:

1 mole of N2 will react to 3 moles of H2

so 6.25 moles of H2 will react to 6.25/3 = 2.03 moles of N2

molar mass of N2 = 2(14.01) = 28.02 g/mol

mass of N2 = 2.03 x 28.02 = 56.88 g

Based on the information provided, we have a reaction between hydrogen iodide (HI) gas and hydrogen gas (H₂) to form iodine gas (I₂). The equilibrium is represented by the equation:

2HI(g) = H₂(g) + I₂(g)

The concentration values given in the table correspond to the concentrations of H₂ and HI at different times.

a) From t=0 s to t=5 s: Without the specific graph mentioned in Figure 7.10, it is difficult to provide a precise explanation of the physical situation in the container during this time period. However, based on the equilibrium reaction given, we can make some general observations. At the start (t=0 s), the concentrations of H₂ and HI may be high. As time progresses, the reaction proceeds, and the concentrations of H₂ and HI may decrease while the concentration of I₂ increases. The specific behavior will depend on the rate of the forward and reverse reactions.

b) External factor altered at t=5 s: To bring about a change in the shape of the graph at t=5 s, some external factor must have been altered. The most likely factor is the total pressure within the container. Since the reaction involves gases, changes in pressure can affect the equilibrium position. However, according to the information given, a change in pressure will not affect equilibrium in this case since the number of moles of gas is the same on both sides of the equation. Therefore, if the shape of the graph changes at t=5 s, some other external factor, such as temperature or the addition of a catalyst, must have been altered.

c) Calculation of K at t=3 s: The equilibrium constant (K) can be calculated at any given time using the concentrations of the reactants and products. However, the concentrations of H₂ and HI at t=3 s are not provided in the information given. Without the necessary data, it is not possible to calculate K at t=3 s.

Lastly, the statement "1 dm³ COCI, decomposes" seems incomplete. If you provide additional information or clarify the question, I'll be happy to assist you further.

Answer: the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

Explanation:

Given the data in the question;

I think the value of electrostatic potential energy of calcium sulfide CaS formed will be less(more negative) than KCl because the Ca2+ and S2- ions has more charge that is +2 and -2 respectively when compared to Kcl which has +1 and -1 charge.so it will be more negative.

radius = r\(_{ca+2}\) + r\(_{s-2}\) = 100 + 184 = 284 pm = 2.84 × 10⁻¹⁰ m

we know that; k = 2.31 × 10⁻²⁸ J

q1 = 2  ( charge on Ca⁺² )

q2 = -2( charge on S⁻²)

so

Ep = k × q1q2/r

so we substitute

Ep = 2.31 × 10⁻²⁸ × (+2×-2) / 2.84 × 10⁻¹⁰

Ep = (2.31 × 10⁻²⁸ × -4) / 2.84 × 10⁻¹⁰

Ep = -9.24 × 10⁻²⁸ / 2.84 × 10⁻¹⁰

Ep = -3.26 × 10⁻¹⁸ J

Therefore, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

Based on the data provided, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J

The electrostatic potential energy is the work done in moving the charge from infinity to that point against the electric field.

The electrostatic potential energy between any two charges q1, q2 separated by distance r is derived from Coulomb’s law and mathematically given as:

where

From the data provided:

ionic radii of Ca2+ r1 = 100 pm

ionic radii of S2– = 184 pm.

Chargeon Ca2+ = +2

Charge on S2_ = -2

From the data above, it most likely that the value of electrostatic potential energy of calcium sulfide CaS formed will be less(more negative) than KCl because the Ca2+ and S2- ions has a greater charge of +2 and -2 respectively compared to Kcl which has +1 and -1 charge.

Calculating the electrostatic potential energy, Ep:

radius = r1 + r2 = 100 + 184 = 284 pm

r = 2.84 × 10⁻¹⁰ m

k = 2.31 × 10⁻²⁸ J

q1 = 2  ( charge on Ca⁺² )

q2 = -2( charge on S⁻²)

Then:

Ep = k × q1q2/r

Substituting the values above in the equation:

Ep = 2.31 × 10⁻²⁸ × (+2 ×-2) / 2.84 × 10⁻¹⁰

Ep = (2.31 × 10⁻²⁸ × -4) / 2.84 × 10⁻¹⁰

Ep = -9.24 × 10⁻²⁸ / 2.84 × 10⁻¹⁰

Ep = -3.26 × 10⁻¹⁸ J

Therefore, the electrostatic potential energy is -3.26 × 10⁻¹⁸ J.

Learn more about electrostatic potential energy at: https://brainly.com/question/24648428

The volume of the gas at STP would be 23.93 liters.

The volume of gas at STP (Standard Temperature and Pressure), we need to use the Ideal Gas Law, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is temperature. First, we need to calculate the number of moles of gas in the initial sample. We can use the formula n = PV/RT, where P is the initial pressure, V is the initial volume, R is the gas constant, and T is the initial temperature.
n = (2.31 atm) x (25.15 L) / [(0.0821 L atm/mol K) x (201 + 273.15 K)]
n = 1.067 moles

Now, we can use the molar volume of gas at STP, which is 22.4 L/mol, to calculate the volume of gas at STP.
V = n x 22.4 L/mol
V = 1.067 moles x 22.4 L/mol
V = 23.93 L
Therefore, the volume of the gas at STP would be 23.93 liters.

For more such questions on gas

https://brainly.com/question/25736513

#SPJ11

The final volume of gas will be 137.17L .

According to ideal gas equation , PV=nRT , where P is pressure of gas , V is volume of gas , n is moles of gas , R is universal gas constant and T is the temprature of gas.

Now , according to the que at initial and final stage the temprature and amount of gas stays constant , so we would simply equate the initial PV to the final PV.

⇒\(P_{i} V_{i} = P_{f} V_{f} \\\)

where \(P_{i}\) ans \(V_{i}\) are the initial pressure and volume of the gas and  \(P_{f}\)  and \(V_{f}\) are the final pressure and volume of the gas .

Here we have to find final volume of gas .

So , putting all values in above eq we get

18 x 22.1 = 2.9 x  \(V_{f}\)

⇒ \(V_{f}\) = 137.17 L

Learn more about ideal gas equation here https://brainly.com/question/25290815

#SPJ10

The time needed for 1 gram of magnesium to react with an excess of dilute sulphuric acid was 2 minutes

Rate of the reaction is directly proportional to the reactant’s concentration. If the concentration decreases by half, then the rate of the reaction also decreases by half as they are directly proportional to each other.

In the table given in the question, we can see that at 1 minute time the reaction starts to give off gas. Thus, for 2g concentration of magnesium, the reaction starts at 1 minute.

Therefore, for 1 gram of reactant (magnesium), the rate of the reaction would be slowed by half. As the rate is slowed, it would take twice the time to react.

Twice the time would be 2 minutes. Thus, the time needed for 1 gram of magnesium to react with an excess of dilute sulphuric acid was 2 minutes

To know more about Rate of the reaction

https://brainly.com/question/13440548

#SPJ1

Solid. Option D is correct

Matter is anthting that has weight and occupies space. The common states of matter that we have are the solid, liquid and gas.

Density is the ratio of mass of a substance to its volume. Among the three states of matter listed, solid state has the highest density due to its efficient packing structure of its molecules compared to liquid and gases.

Answer:

I think that option D is correct.

Explanation:

I think that option D is correct because it most have highest density.

The most accurate statement about signal transmissions among the given options is:

a) All signals in transmission will lose clarity with distance.

When a signal is transmitted over a distance, it can experience various types of degradation or attenuation. Factors such as distance, interference, noise, and the medium through which the signal travels can all contribute to a reduction in the clarity or quality of the signal. This means that as the distance between the source and receiver increases, the signal may become weaker, distorted, or prone to interference, resulting in a loss of clarity.

A hypothesis is a proposed explanation or prediction based on limited evidence or observations, which can be tested through further investigation or experimentation. It should be specific, testable, and based on existing knowledge.

For such more question on hypothesis

https://brainly.com/question/606806

#SPJ8

Answer:

Explanation:

As a result, the reaction of propane (C H) 3 8 and oxygen should produce carbon dioxide, water, and heat as products, and the balanced chemical equation will be: C H3 8 + 5O2 3CO2 + 4H O2 + heat. Reactants have the next highest potential power level when compared to materials.

Answer:

water and carbon dioxide

Explanation:

Propane undergoes combustion reactions in a similar fashion to other alkanes. In the presence of excess oxygen, propane burns to form water and carbon dioxide.

I hope this helps!

Explanation:

kinetic energy?? idek hope I helped in anyway possible

Answer:

7.5 joules also 7.5 J

Explanation:

The balanced nuclear equation for the beta decay of 234/90Th can be represented as follows: ^234/90Th --> ^234/91Pa + e^0/-1β

In this equation, the nucleus of thorium-234 (234/90Th) undergoes beta decay. During beta decay, a neutron within the nucleus is converted into a proton, resulting in the emission of an electron (beta particle). As a result, the thorium-234 nucleus is transformed into protactinium-234 (234/91Pa) by gaining one proton.

The beta particle emitted during the decay process is represented as e^0/-1β, where the superscript 0 denotes that the electron has no charge (neutral), and the subscript -1 indicates that the electron carries a negative charge of -1.

It is important to note that in a nuclear equation, the total atomic mass and atomic number on both sides of the equation must be equal to maintain a balanced equation and conserve mass and charge.

For more such questions on balanced nuclear equation visit:

https://brainly.com/question/31505524

#SPJ8

Answer:

The end point of a titration is the point at which the reaction between the analyte (the substance being analyzed) and the titrant (the solution being added to the analyte) is complete. The end point is usually determined by a change in the color of the solution, and this change is typically caused by an indicator added to the analyte solution.

The indicator is a substance that changes color at or around the pH at which the reaction is complete. The indicator is chosen based on the properties of the analyte and titrant, and the pH range over which the reaction occurs. Common indicators include phenolphthalein, bromothymol blue, and methyl orange.

For example, when titrating a strong acid (like HCl) with a strong base (like NaOH), phenolphthalein is often used as the indicator. The phenolphthalein molecules are colorless in acidic solution, but they turn pink in basic solution. As the NaOH is added to the HCl, the solution becomes increasingly basic. Once the pH reaches the endpoint, the indicator turns pink. This indicates that the reaction is complete and no further addition of NaOH is required to completely react with the HCl.

The endpoint determination is critical in performing accurate titrations. The endpoint must be identified accurately and consistently in order to obtain reliable and reproducible results.

A titration is a technique that is used to measure the concentration of an unknown substance in a solution using a standard solution with a known concentration. The endpoint of a titration is the point at which the reaction between the two solutions is complete, and no more titrant (standard solution) is needed to react with the analyte (unknown substance). There are several ways to recognize the endpoint of a titration, including:1. Indicators: An indicator is a substance that changes color when the endpoint is reached.

For such more question on titration

https://brainly.com/question/13031875

#SPJ8

The half equation for this reaction is 2H2 + O2 = 2H2O and this is reduction because it is taking place in cathode.

Does cathode or anode decrease occur?

Although the direction of spontaneous electron flow in galvanic cells may be reversed in electrolytic cells, the definitions of cathode and anode where reduction takes place at the cathode and oxidation happens at the anode remain the same.

Which ions undergo cathodic reduction?

The positively charged ions will migrate toward the cathode after becoming reduced by receiving electrons. Since positive ions pick up electrons at the negative cathode, reduction takes place there.

Know more about cathode- brainly.com/question/2349926

#SPJ1

Answer:

then use those and set up one

Explanation:

Answer:

the string and the cans for me. its like your own phone

Explanation:

427 g Mo

Chemistry

Atomic Structure

Math

Pre-Algebra

Order of Operations: BPEMDAS

Step 1: Define

2.68E24 atoms Mo or 2.68 × 10²⁴ atoms Mo

Step 2: Identify Conversions

Avogadro's Number

Molar Mass of Mo - 95.94 g/mol

Step 3: Convert

\(2.68 \cdot 10^{24} \ atoms \ Mo(\frac{1 \ mol \ Mo}{6.022 \cdot 10^{23} \ atoms \ Mo} )(\frac{95.94 \ g \ Mo}{1 \ mol \ Mo} )\) = 426.966 g Mo

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

426.966 g Mo ≈ 427 g Mo

Answer:

The initial pressure was 852.27 torr.

Explanation:

Given that,

Initial temperature, T = 315 K

Final temperature, T' = 231 K

Final pressure, P' = 625 torr

We need to find the initial pressure of the gas. We know that, the relation between pressure and temperature is given by :

\(\dfrac{P}{P'}=\dfrac{T}{T'}\\\\P=\dfrac{P'T}{T'}\\\\P=\dfrac{625\times 315}{231}\\\\P=852.27\ torr\)

So, the initial pressure was 852.27 torr.

Acetic acid only partially ionizes in water as it is a weak acid.

Weak Acids are the acids that do not completely dissociate into their constituent ions when dissolved in solutions.

When dissolved in water, an equilibrium is established between the concentration of the weak acid and its constituent ions.

Acetic acid, also known as ethanoic acid, is a weak acid with the chemical formula CH₃COOH. It is known to be the active component of vinegar.

Learn more about Weak acids, here:

https://brainly.com/question/22104949

#SPJ1

Answer:

may involve a change in total mass

involve very high-energy changes

involve changes in nuclides when decay occurs

Explanation:

A nuclear reaction is different from a typical chemical reaction. The reaction occurs within the nucleus and involved nuclear materials.

To get the number of moles of Cu, look up its molar mass. The mole ratio of Cu to Ag is 1:1 if the reaction is Cu(s) + AgNO3(aq) CuNO3(aq) + Ag(s).

Copper has a molar mass of 63.5 g/mol. Page 15 Molar Mass: An Overview The atomic mass of a copper atom is 63.5 amu. Copper has a molar mass of 63.5 g/mol.

You need to know the product's mass and its molar mass (g/mol), which is the mass of one mole of the product, in order to calculate the moles of a substance. The product's molar mass is then divided by the product's mass.

To know more about moles visit:-

https://brainly.com/question/26416088

#SPJ1

Answer:

Both resulted in gas formation. Both resulted in color change.

Explanation:

Follow me!

Answer:

statement second and third are both corect

Explanation:

When iron(grey) reacts with sulfur(yellow) chemical change takes place in which iron sulfide is formed which black in color.

Fe(s) + S(s)\rightarrow FeS(s)Fe(s)+S(s)→ FeS(s)

When we heat copper sulfate-pentahydrate(blue) ,water molecule present in its crystal will get evaporated and it will become an anhydrous copper sulfate which will be white in color.

CuSO_{4}.5H_{2}O(s)\overset{heat}{\rightarrow} CuSO_{4}(s)+5H_2O(g)CuSO

4

.5H

2

O(s)

→

heat

CuSO

4

(s)+5H

2

O(g)

So, in both the reactions chang

request:

set as brainiest

Answer:

Yes

Explanation:

big brain

Answer:

5997 kg

Explanation:

Hope this helps

By removing the need to build additional transmission lines and equipment, energy storage may reduce costs for utilities and their customers.

By removing the need to build additional transmission lines and equipment, energy storage may reduce costs for utilities and their customers. Energy storage's inherent ability to offer backup power in the event of grid failure is a feature that both residential consumers and commercial owners find highly desirable.

To know more about energy, here:

https://brainly.com/question/1932868

#SPJ1