Using complete sentences, why do you think we need to use time zones on earth?

Answer:

Explanation:

For work to be done, force must be applied to move an object in the direction of the applied force.

Work is the product of force and distance. Workdone describes a change of energy between places.

If we apply force to a body without moving it through a distance, no work is done.

Work is only done when force is applied to move or displace a body.

If we only apply force and no movement occurs, no work is done..

The unit of force is Joules.

In physics, work is done when a force is applied to an object and the object is displaced in the direction of the force. The work done is the product of the force's component in the direction of displacement and the distance the object moves. No displacement in the direction of the force means no work is done, even if effort is exerted.

In physics, for work to be done, two primary conditions must be fulfilled. First, a force must be applied to an object. Second, the object must experience a displacement in the direction of the force. If either of these conditions is not met, work is considered not to have occurred, regardless of the effort put in. For example, pushing against a wall with great effort does not constitute work unless the wall moves. If the wall does move, the energy used to cause this movement is the work done.

The work done is mathematically defined by the dot product of the force and displacement vectors, signifying that the direction of the force relative to the displacement is crucial in calculating the work performed. Therefore, when an external force causes an object to move, and this movement is in the same direction as the force, the product of the force's component along the direction of displacement and the distance moved is the work done. This could mean overcoming resisting forces like friction and moving a mass along a surface, or it could imply the conversion of one type of energy into another.

Answer:

The limiting reactant is AlCl₃ and the excess reactant is NaOH.

Explanation:

3NaOH(aq) + AlCl₃(aq) → 3NaCl(aq) + Al(OH)₃(s)↓,

It is clear that 3.0 moles of NaOH(aq) react with 1.0 mole of AlCl₃(aq) to produce 3.0 moles of NaCl(aq) and 1.0 mole of Al(OH)₃(s).

no. of moles of NaOH = mass/molar mass = (8.0 g)/(40.0 g/mol) = 0.2 mol.

no. of moles of AlCl₃ = mass/molar mass = (4.0 g)/(133.34 g/mol) = 0.03 mol.

∴ 0.09 mol of NaOH (the remaining 1.1 mol is in excess) reacts completely with 0.03 mol of AlCl₃.

the limiting reactant is AlCl₃ and the excess reactant is NaOH.

Answer:

b. Drainage basin

Explanation:

Answer:

A) Homogeneous

Explanation:

Hope this helped :)

Earth's atmosphere is unique due to the presence of life that has influenced its composition, unlike the atmospheres of Venus and Mars, which do not support life and have atmospheres dominated by carbon dioxide and lacking in water vapor.So,option B is correct.

The composition of Earth's atmosphere is different from the atmospheres of Venus and Mars primarily because Earth has life, and Venus and Mars do not. This is option B. All three planets started with similar chemicals, but their evolutionary paths diverged because of factors such as their distance from the sun and geological activities. Earth's atmosphere, rich in oxygen and water vapor, not only supports life but has been shaped by it through processes like photosynthesis. In contrast, Venus has a thick atmosphere dominated by carbon dioxide with extreme surface pressure and temperature, making it hot and dry. Mars has a thin atmosphere, also mostly carbon dioxide, and is cold and dry, but it has signs that it once had conditions suitable for life.

The presence or absence of life significantly influences the atmospheric composition. Life on Earth has contributed to the oxygen levels and the presence of water vapor. The lack of life on Venus and Mars means that these planets have been unable to develop the same balance of gases that supports life here on Earth. Consequently, each planet's atmosphere is a result of its unique environmental conditions and history.

Answer:

Explanation:

A hydrated compound is one that contains water molecules chemically bonded. So,  the correct question is how many waters are bonded to sodium suilfate?

The latin prefix deca means ten (10), and the word hydrate means that contains water; then, decahydrate is used in chemistry to designate a compound that is bonded to 10 parts (molecules) of water.

Hence, sodium sulfate decahydrate means that each molecule of the compound is bonded to 10 molecules of water.

In the chemical formula, the water molecules of a hydrated compound are shown after the chemical formula of the compound using a period and a coefficient (the number of water molecules bonded) before the water molecules.

Then, given that the chemical formula for sodium sulfate is Na₂SO₄, the chemical formula for sodium sulfate decahydrate is Na₂SO₄·10H₂O.

Bromine --> Br: Period 4, Group 17 [Halogen]

Answer:

D. Extra-strong

Explanation:

a p e x

Answer:

C: It is conserved

Explanation:

The reaction neither lost (exothermic) or gained (endothermic) energy, therefore the total energy remained the same and was conserved.

Answer:

D: It is converted

Explanation:

according to the law of conservation of energy:

In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time.

Meaning that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another without any loss of energy

Every half-life, we end up with half of the material we started with. At the beginning, we have all of the material, which we can represent with the number 1. After one half-life, we have 1 • 1/2 = 1/2 left.

After two: 1/2 • 1/2 = 1/4

Three: 1/4 • 1/2 = 1/8

Four: 1/8 • 1/2 = 1/16

And five: 1/16 • 1/2 = 1/32.

In general, after n half-lives, we’ll have 1/(2^n) of the material left over.

Answer:

The correct answer is :1 by 32 of the original sample

Explanation:

Formula used :

[tex]A=\frac{A_o}{2^n}[/tex]

where,

A = amount of reactant left after n-half lives = ?

[tex]A_o[/tex] = Initial amount of the reactant = 100 g

n = number of half lives

If five half-lives have occurred.

[tex]A=\frac{A_o}{2^5}[/tex]

[tex]A=\frac{A_o}{32}[/tex]

Hence, the correct answer is :1 by 32 of the original sample

A pH is an easy way to describe the acidity of a solution (determined by the [H+] concentration) - it’s easier to say that a cup of coffee has a pH of 5 rather than saying that the “hydrogen ion concentration is 10^-5 molar”.

The way pHs work is through logarithms, which convert a set of values into a new one using a base value. For example, pHs use a base 10 to simplify the numbers, while earthquake energy scales use a base of 32. An increase of 1 on the logarithmic scale is an “n” times increase in the scale, where “n” is the base of the logarithm. So, for example, in the case of pH, three solutions with a pH of 5, 6, and 7 can be related; the pH scale uses base ten, so the pH 6 solution is 10x more acidic than the pH 7, and the pH 5 is 100x (10x10) more acidic than the pH 7. For earthquakes, a magnitude 5 earthquake is 32x weaker than a magnitude 6 and 1,024x (32x32) weaker than a magnitude 7.

The pH formula looks like this:

pH = -log [H+]

The negative sign basically serves to make the low end acidic; without the negative, a pH of 14 would be extremely acidic instead of basic. It’s one of those things that you’ll just have to remember.

So, for your solution, just enter the concentration into the formula:

pH=-log[1.0 x 10^-4] = 4

The pH of this solution would be 4.

Hope this helps!

Answer:

D

Explanation:

The reactants are butane gas and oxygen, and the product is carbon dioxide and water VAPOR. The letter beside the water formula means it's a gas.

Final answer:

The correct word equation is that butane gas reacts with oxygen gas to form carbon dioxide gas and water vapor. This is a combustion reaction where the hydrocarbon butane combusts in the presence of oxygen to produce these products.

Explanation:

The correct word equation for the reaction 2C₄H₁₀ (g) + 13O₂ (g) ⇒ 8CO₂ (g) + 10H₂O (g) is D) Butane gas reacts with oxygen gas to form carbon dioxide gas and water vapor.

In this reaction, butane (C₄H₁₀) and oxygen (O₂) are the reactants, while carbon dioxide (CO₂) and water (H₂O) are the products. Since the reaction includes the conversion of gases and no liquids are mentioned in the context of products, we can conclude that the water produced is also in gaseous form which is commonly referred to as water vapor.

A complete combustion reaction always yields carbon dioxide and water as products, assuming ample oxygen is available. If the reaction had incomplete combustion, carbon monoxide (CO) could be present, but this is not indicated in the given equation.

Answer:

66

Explanation:

The number of neutrons is the atomic number (25) subtracted from the mass (91). So, 91 - 25 = 66.

Answer:

16.27 g.

Explanation:

Using cross multiplication:

1.0 mol of N₂ gas contains → 6.022 x 10²³ molecules.

??? mol of N₂ gas contains → 3.50 x 10²³ molecules.

∴ The no. of moles of N₂ gas = (1.0 mol)(3.50 x 10²³ molecules)/(6.022 x 10²³ molecules) = 0.5812 mol.

∴ The mass of 3.50 x 10²³ molecules of N₂ gas = (no. of moles)*(molar mass) = (0.5812 mol)(28.0 g/mol) = 16.27 g.

Final answer:

To calculate the mass of 3.50x10²³ molecules of nitrogen gas, we apply the concept of molar mass (28.01 g/mol) and Avogadro's number, resulting in a mass of approximately 16.3 grams.

Explanation:

To find the mass of 3.50x10²³ molecules of nitrogen gas (N₂), we must first understand the concept of molar mass and Avogadro's number (6.02x10²³ mol⁻¹). The molar mass of N₂ is 28.01 g/mol, which means one mole (6.02×10²³ molecules) of nitrogen gas has a mass of 28.01 grams.

To calculate the mass of 3.50×10²³ molecules, we use the proportion method:

1 mole (6.02×10²³ molecules) : 28.01 g = 3.50×10²³ molecules : X g

Solving for X gives us the mass of the nitrogen gas:

X = (3.50×10²³ / 6.02×10²³) × 28.01 g

Therefore, X = 16.3 grams (approximately).

This calculation illustrates how we can determine the mass of a specific number of gas molecules using the principles of molar mass and Avogadro's number.

The energy change of the system was calculated using the formula q = mcΔT. After finding the energy change per gram of water, it was converted to energy change per mole of solute giving the heat of the solution, ΔH = -8.0 kJ/mol.

The energy change in a system is given by the formula: q = mcΔT, where m is the mass of the system, c is the specific heat capacity and ΔT is the change in temperature.

We are given that the temperature decreases so the reaction is endothermic (heat is absorbed) and we use a positive q. The mass of the water is 100g, c for water is 4.18 J/g°C, and ΔT = Final temp - Initial temp = 21.56°C - 25.00°C = -3.44°C.

So, q for water = (100g)*(4.18 J/g°C)*(-3.44°C) = -1438.72 J. We want the answer per mol NaNO3 so we get the molar mass of NaNO3= 85 g/mol. So 15.3 g is 15.3 g ÷ 85 g/mol = 0.18 mol NaNO3.

Finally, q for the solution = q for water ÷ moles of solute = -1438.72 J ÷ 0.18 mol = -7993.7 J/mol. This is the heat of solution in J the question asks for the answer in kJ so we convert, ΔH = -8.0 kJ/mol.

https://brainly.com/question/30437871

#SPJ12

To calculate Delta H for a solution in a calorimeter, utilize the formula for specific heat capacity, and then calculate the change in enthalpy on basis of moles of solute and heat energy extracted. This example uses nano3 as the solute in a water solution and measures the corresponding decrease in temperature.

The process of calculating Delta H involves using the formula for specific heat capacity Q = mcΔt, which is heat energy equals mass times specific heat capacity times change in temperature. The change in enthalpy, or Delta H, is then -Q divided by the number of moles of the solute, which in this case is nano3. With the given values, we can use the specific heat capacity of water (4.184 J/g°C), the mass of water (100g), and the change in temperature (25.00°C to 21.56°C). Performing necessary calculations, we finally find the value of Delta H for this solution process.

Specific heat capacity, change in enthalpy (Delta H), and moles of solute are the principal factors in determining the behavior of this solution in the calorimeter.

https://brainly.com/question/35541255

#SPJ12

Answer:

a.) 86.01 g.

b.) 3.36 g.

c.) 0.394 m ≅ 0.40 m.

d.) 4.77%.

e.) 3.9%.

Explanation:

a.) mass of the solution:

The density of the solution is the mass per unit volume.

∵ Density of solution = (mass of solution)/(volume of the solution).

∴ Mass of the solution = (density of solution)*(volume of the solution) = (1.22 g/mL)*(70.5 mL) = 86.01 g.

b.) grams of sodium bromide  :

∵ M = (no. of moles of NaBr)/(Volume of the solution (L))

∴ no. of moles of NaBr = M*(Volume of the solution (L)) = (0.463 M )*(0.0705 L) = 0.0326 mol.

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

∴ mass of NaBr = (no. of moles of NaBr)*(molar mass of NaBr) = (0.0326 mol)*(102.894 g/mol) = 3.36 g.

c.) molality of the solution:

∵ m = (no. of moles of NaBr)/(mass of the soluvent (kg))

no. of moles of NaBr = 0.0326 mol,

mass of solvent = mass of the solution - mass of NaBr = 86.01 g - 3.36 g = 82.65 g = 0.08265 kg.

∴ m = (no. of moles of NaBr)/(mass of the soluvent (kg)) = (0.0326 mol)/(0.08265 kg) = 0.394 m ≅ 0.40 m.

d.) % (m/v) of the solution:

∵ (m/v)% = [(mass of solute) /(volume of the solution)]* 100

∴ (m/v)% = [(3.36 g)/(70.5 mL)]* 100 = 4.77%.

e.) % (m/m) of the solution:

∵ (m/m)% = [(mass of solute) /(mass of the solution)]* 100

∴ (m/m)% = [(3.36 g)/(86.01 g)] * 100 = 3.9 %.

Final answer:

When water boils, the water’s internal kinetic energy increases, and upon reaching the boiling point, the energy input turns into potential energy to convert water to steam. Air bubbles seen are not from the atmosphere but from dissolved gases, and the water's temperature does not increase beyond the boiling point.

Explanation:

When water is boiling in a pot, several physical changes occur. The water’s internal kinetic energy is increasing due to the heat supplied, which causes the water molecules to move faster. As the temperature of the water reaches the boiling point, the added energy goes into breaking the intermolecular forces, converting liquid water into water vapor, which is observed as boiling. This process is known as the phase transition from liquid to gas.

Air bubbles from the atmosphere are not being absorbed; instead, existing dissolved gases in the water can form bubbles. The water's temperature does not continue to increase once it reaches the boiling point, which for pure water at sea level is 100°C. At this point, any extra energy supplied by the stove is used to turn the water into steam, which is a process that involves gaining internal potential energy, rather than increasing temperature. Lastly, individual water molecules are indeed escaping from the pot, forming steam as they enter the gas phase.

Answer:

Organic chemistry is a subdiscipline of chemistry that studies the structure, properties and reactions of organic compounds, which contain carbon in covalent bonding. Study of structure determines their chemical composition and formula.

Answer:

Ag(s) or Solid Silver. Silver in a solid phase has a face centered cubic crystal structure. Among your choices, silver is the only example of particles that are arranged in their crystal structure while the other choices are gases and liquid. Liquid and gases have loose atoms that do not form crystal structures.

Explanation:

Final answer:

The use of aerosol sprays and coolants that release chlorine and bromine gases contributes to ozone layer destruction, leading to increased UV radiation and environmental harm. The Montreal Protocol helped reduce emissions of ozone-depleting substances, slowing the rate of depletion.

Explanation:

The human activity that most likely contributes to ozone layer destruction is the release of chlorine and bromine gases through the use of products like aerosol sprays and coolants. These substances are known as ozone-depleting substances (ODS), and include chemicals such as chlorofluorocarbons (CFCs).

When these substances reach the stratosphere, they release halogen radicals that catalytically destroy ozone molecules, leading to ozone depletion. This has severe environmental and health impacts, such as increased UV radiation leading to higher rates of skin cancers and disrupted ecosystems. The Montreal Protocol was a successful international effort to phase out the production and use of ODS, which has led to a decrease in the rate of ozone depletion, but vigilance and continued reduction of emissions are essential to protect the ozone layer.

This is filler, the answer is in the image.

Answer: I think it is HPDE.

Answer:

It is the Avogadro's Law that should be used  to determine the relationship between the volume and the number of moles in the equation. This law relates the volume and the the amount in moles of a gas.

that should be used  to determine the relationship between the volume and the number of moles in the equation. This law relates the volume and the the amount in moles of a gas.

Answer:

Volume = lwh

Explanation:

Solution is here,

for initial case,

temperature(T1)=70°C=70+ 273=343K

vloume( V1) =45 L

for final case,

temperature( T2)=?

volume(V2)= 91.3 L

at constant pressure,

V1/V2 = T1/T2

or, 45/91.3 = 343/ T2

or, T2= (343×91.3)/45

or, T2=695.9 K = (695.9-273)°C=422.9°C

The temperature needed for a sample of gas to occupy 91.3 L, when originally it occupied 45.0 L at 70.0°C at constant pressure, is about 423.71°C.

This question pertains to the ideal gas law equation (P1V1/T1 = P2V2/T2, where P is pressure, V is volume, and T is temperature), we must first convert our temperatures to Kelvin (K) since the ideal gas law uses absolute temperature. To convert from degrees Celsius to K, add 273.15, thus 70.0°C becomes 343.15K. As the problem states pressure is constant, we can ignore that component of the equation and it simplifies to V1/T1 = V2/T2.

By rearranging the equation to solve for V2, we get V2 = V1 (T2/T1). Given the volume of the gas at the initial temperature (V1 = 45.0 L), and temperature T2 with unknown value, we rewrite the equation as T2 = (V2 * T1) / V1. Substituting the given values into the equation gives T2 = (91.3 L * 343.15K) / 45.0 L, which calculates to approximately 696.86K, converting back to Celsius gives us around 423.71°C.

So, your sample of gas would need to be heated to approximately 423.71°C in order for it to occupy a volume of 91.3 L at constant pressure.

https://brainly.com/question/30458409

#SPJ3

The acid dissociation constant (Ka) for acetic acid, given the initial concentration of 0.200 M and the equilibrium concentration of H3O+ is 0.0019 M, is 1.82 × 10⁻µ.

To calculate the acid dissociation constant (Ka) for acetic acid, we can use the information provided that the initial concentration of acetic acid is 0.200 M and the equilibrium concentration of H3O+ is 0.0019 M. Using the chemical equation for the dissociation of acetic acid (CH3COOH):

CH3COOH(aq) ⇌ CH3COO−(aq) + H3O+(aq),

we know that at equilibrium, the concentration of H3O+ ions will be the same as the concentration of CH3COO− ions. Therefore, [CH3COO−] = [H3O+] = 0.0019 M.

Because acetic acid is a weak acid, we can assume that the change in concentration of acetic acid is roughly equal to the concentration of H3O+ ions produced. Thus, the equilibrium concentration of CH3COOH will be 0.200 M - 0.0019 M = 0.1981 M. The formula for Ka is:

Ka = [CH3COO−][H3O+] / [CH3COOH]

Substituting the equilibrium concentrations into this formula gives:

Ka = (0.0019 M)(0.0019 M) / (0.1981 M) = 1.82 × 10⁻µ,

which is the Ka for acetic acid.

Answer: Acceleration can be defined as the rate at which velocity changes

Acceleration has the units m/s2.

Hope this helps! :D

Hello There!

"ACCELERATION" can be defined as the rate at which velocity changes

Answer:

your answer is B:  Hydrogen sulphide

Explanation:

C, because specific heat is measured in Joules/grams°C

Answer: B) 1 Calorie

Explanation: The heat required to raise the temperature of 1 gram of a substance by 1 degree C is known as its specific heat capacity.

Specific heat capacity of water is [tex]\frac{4.184Joule}{g*0_C}[/tex] and we know that, 4.184 Joule = 1 Calorie

So, specific heat capacity of water is [tex]\frac{1Calorie}{g*0_C}[/tex] and hence the correct choice is B.

Answer:

A reaction is spontaneous if ΔG is negative.

Explanation:

If ΔG is negative, the reaction is spontaneous.

If ΔG = zero, the reaction is at equilibrium.

If ΔG is positive, the reaction is non-spontaneous.

It is the first one that's correct...

Science is characterized by asking questions about the natural world. It involves a methodical process of observation, hypothesizing, experimentation and conclusion. Science does not use opinions to make conclusions but relies on systematic observation, experimentation and testing to ascertain facts.

A characteristic of science is that it asks questions about the natural world. This process is often initiated by observation, leading scientists to generate questions they wish to answer. Science employs systematic methods for observing the universe, forming theories and testing hypotheses to understand how the world operates.

In essence, science seeks to discover and describe the underlying order within nature. It's through the rigorous processes of observation, hypothesis formulation, experimentation, and conclusion that science separates facts from opinion, aiming to describe the universe accurately as it is and not as imagined or wished.

This investigative approach isn't conducted by single individuals; it's a collaborative endeavor involving many scientists. Most importantly, science does not use opinions to draw conclusions. Rather, it bases conclusions on evidence and facts gathered systematically through experiments, observations, and testing.

https://brainly.com/question/4953861

#SPJ3

Answer:

28.28 L.

Explanation:

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

P₁V₁ = P₂V₂

P₁ = 700.0 mm Hg, V₁ = 4.0 L.

at burst: P₂ = 99.0 mm Hg, V₂ = ??? L.

∴ V₂ = P₁V₁/P₂ = (700.0 mm Hg)(4.0 L)/(99.0 mm Hg) = 28.28 L.