Which orbital diagram represents helium (atomic number = 2)?​

The types of chemical reaction for the reactions given are.

Synthesis: H₂O + SO3 → H₂SO4

Decomposition: PbSO4 → PbSO3 + O2

Single- Replacement: Mg + Fe2O3 → Fe + MgO

Double- Replacement: NaBr + H3PO4 → Na3PO4 + HBr

Combustion: C2H4 + O2 → CO2 + H2O

Therefore, A chemical reaction is a process that leads to the transformation of one set of chemical substances to another set. In other words, it is the process by which atoms are rearranged to create new chemical compounds.

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The decrease in temperature is 147.075 K. The SI unit for temperature is the kelvin (K), but it can also be measured in degrees Celsius (°C) or Fahrenheit (°F).

What is Temperature?

Temperature is a physical property that measures the degree of hotness or coldness of an object or system, as compared to a standard reference point. It is a measure of the average kinetic energy of the particles (atoms or molecules) in a substance or system.

To solve this problem, we need to use the Charles's law equation which states:

V1/T1 = V2/T2

where V1 and T1 are the initial volume and temperature, and V2 and T2 are the final volume and temperature.

We can rearrange the equation to solve for T2:

T2 = (V2/T2) x T1

First, we need to convert the initial temperature from Celsius to Kelvin by adding 273.15:

T1 = 21.0°C + 273.15 = 294.15 K

The initial volume (V1) is 6.0 L, and the final volume (V2) is 3.0 L. Substituting these values into the equation, we get:

(6.0 L/294.15 K) = (3.0 L/T2)

Solving for T2, we get:

T2 = (3.0 L x 294.15 K) / 6.0 L

T2 = 147.075 K

Finally, we can find the decrease in temperature by subtracting the final temperature (T2) from the initial temperature (T1):

ΔT = T1 - T2

ΔT = 294.15 K - 147.075 K

ΔT = 147.075 K

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The equilibrium concentrations of CO₂, H₂, and CO are 0.170 M, 0.084 M, and 0.016 M, respectively.

Making an equilibrium concentration calculation. A chemical reaction is said to be in a state of chemical equilibrium when both the reactants and the products are in a concentration that does not vary over time any longer.

The reaction's equilibrium constant formula is as follows:

Kc = ([CO][H₂O])/([CO₂][H₂])

We obtain the following by plugging in the equilibrium amounts from the ICE table:

Kc = ((x)(0.0856))/((0.20 - x)(0.10 - x))

b. In order to determine Kc, we must first determine x using the equilibrium formula and the specified equilibrium H₂O concentration:

Kc = ((x)(0.0856))/((0.20 - x)(0.10 - x)

Kc = (x(0.0856))/(0.02 - 0.3x + x - 0.01x)

Kc = (x(0.0856))/(0.02 - 0.21x)

Kc(0.02 - 0.21x) = 0.0856x

0.02Kc - 0.21Kcx = 0.0856x

0.21Kcx + 0.0856x = 0.02Kc

x(0.21Kc + 0.0856) = 0.02Kc

x = (0.02Kc)/(0.21Kc + 0.0856)

x = (0.02Kc)/(0.21Kc + 0.0856

After solving for the equilibrium concentrations of CO₂, H₂, and CO and substituting this equation for x back into the ICE table, we arrive at:

[CO₂] = 0.170 M

[H₂] = 0.084 M

[CO] = 0.016 M

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Answer:

Explanation:

These are the transition metals.  Groups 3-12 also know as the "d" block elements

Answer:

C. Energy is absorbed.

Explanation:

In an endothermic reaction, energy is absorbed from the surroundings, resulting in an increase in the internal energy of the system. This means that the products of the reaction have a higher energy content than the reactants, and energy is stored in the chemical bonds of the products.

Therefore, option C, energy absorption, occurs in an endothermic reaction.

The Henderson-Hasselbalch equation can be used to calculate the mole ratio of ammonia to ammonium chloride pH is equal to pKb plus [tex]log(NH3/NH4Cl).[/tex]

Figure 1 depicts the chemical equation for producing ammonia and demonstrates that the mole ratio of ammonia to nitrogen gas is [tex]2:1[/tex]. As seen in the chemical reaction, one mole of nitrogen gas results in the production of two moles of ammonia.

By dividing the total number of moles by the smallest number of moles, you may determine the ratio or the number of moles of each element.

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Answer:

Here are the chemical reactions for the formation of the respective Grignard reagents from the reaction of magnesium with the following organic halides:

Mg + CH3I → CH3MgI

Mg + C6H5Br → C6H5MgBr

Mg + C3H7Cl → C3H7MgCl

Grignard reagents are formed when magnesium metal is reacted with an alkyl halide. The magnesium metal reacts with the halide to form a magnesium halide salt, and the alkyl group is displaced from the halide to form the Grignard reagent.

The Grignard reagent is a powerful nucleophile and can be used to synthesize a variety of organic compounds.

Answer: D. Intensity

Explanation: Intensity is correct, because if you originally were working on a treadmill with a speed of 8, that is how much intensity your putting your body on. And if you put the speed for a treadmill at 11 to increase your exercise, you are increasing the speed you have to run, making it more intense. The more intense you make your workout or training, the more stressful exercise you are doing.

Hope this helps,

:)

The internal energy change for the combustion of decane is -6709097.77 J/mol.

How heat is defined by calorimeter?

The heat absorbed by the calorimeter is given by the expression:

q = CΔT

where q is the heat absorbed by the calorimeter, C is the heat capacity of the calorimeter, and ΔT is the change in temperature of the calorimeter.

Substituting the given values, we get:

q = 810.1 J/ C x (78.8 C - 20.0 C) = 47213.48 J

This heat is released during the combustion of decane. Therefore, the enthalpy change for the combustion of decane (ΔH) can be calculated using the expression:

ΔH = -q/moles of decane

The molecular weight of decane is 142.28 g/mol. Therefore, the number of moles of decane in 1.000 g of decane is:

moles of decane = mass of decane / molecular weight of decane

= 1.000 g / 142.28 g/mol

= 0.007032 mol

Substituting the values, we get:

ΔH = -47213.48 J / 0.007032 mol = -6709097.77 J/mol

This is the enthalpy change for the combustion of decane. However, we are asked to calculate the internal energy change (ΔE) for the combustion of decane. The relationship between enthalpy change and internal energy change is given by the expression:

ΔH = ΔE + PΔV

where P is the pressure and ΔV is the change in volume. In the case of a bomb calorimeter, the volume remains constant, and therefore ΔV is zero. Therefore, we can write:

ΔH = ΔE

Substituting the value of ΔH, we get:

ΔE = -6709097.77 J/mol

Therefore, the internal energy change for the combustion of decane is -6709097.77 J/mol.

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The calculations show that Mg(OH)₂ has a solubility of  3.5 × 10⁻⁵ M at a pH of 12.80.

The term pH, which stands for "potential of hydrogen ions," can be interpreted as a measurement of the molar concentration of hydrogen ions in a particular solution. Hence, the acidity, neutrality, or basicity of any chemical solution is often determined or specified using the power of hydrogen ions (pH).

Mg(OH)₂⇔Mg²⁺(aq)+2OH⁻(aq)

First of all, we would write the chemical equation for this chemical reaction that is appropriately balanced

The Ksp for the aforementioned chemical reaction is determined mathematically by:

Ksp = [Mg²⁺][OH⁻]²

Ksp = [x][2x]²

1.6 × 10⁻¹³ = 4x³

x = ∛4 × 10⁻¹⁴

x = 3.5 × 10⁻⁵ M.

The maximum amount of a chemical that will dissolve in a particular amount of solvent at a particular temperature is known as its solubility. Different compounds have very varying solubilities, which is a characteristic of a particular solute-solvent pair.

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Explanation:

The molar mass of lithium chloride (LiCl) is approximately 42.39 g/mol.

To calculate the mass of LiCl that contains 8.75 g of chloride, we need to determine the amount of LiCl that corresponds to 8.75 g of chloride.

The chloride ion (Cl-) has a molar mass of approximately 35.45 g/mol. Therefore, the number of moles of chloride present in 8.75 g of chloride is:

8.75 g / 35.45 g/mol = 0.247 mol Cl-

Since each mole of LiCl contains 1 mole of Cl-, the number of moles of LiCl that contains 0.247 mol of Cl- is also 0.247 mol.

Therefore, the mass of LiCl that contains 8.75 g of chloride is:

0.247 mol LiCl x 42.39 g/mol = 10.46 g LiCl (rounded to two decimal places)

Therefore, 10.46 g of lithium chloride would contain 8.75 g of chloride.

As per the given details, 10.45 grams of lithium chloride would contain 8.75 grams of chloride.

We must first estimate the molar mass of chloride and then use stoichiometry to connect it to the molar mass of lithium chloride (LiCl), in order to calculate the mass of LiCl that would contain 8.75 grammes of chloride.

The molar mass of chloride (Cl) = 35.45 g/mol.

The molar mass of lithium chloride = 42.39 g/mol.

(8.75 g chloride) / (35.45 g/mol chloride) = (x g lithium chloride) / (42.39 g/mol lithium chloride)

Solving for the variable:

x = (8.75 g chloride) * (42.39 g/mol lithium chloride) / (35.45 g/mol chloride)

x ≈ 10.45 g lithium chloride

Thus, approximately 10.45 grams of lithium chloride would contain 8.75 grams of chloride.

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Once alcohol is in the bloodstream it will reach the brain in a few seconds to minutes, depending on various factors such as the amount and concentration of alcohol consumed, body weight, metabolism, and other individual factors.

Alcohol can swiftly cross the blood-brain barrier after it is ingested, having an impact on the brain and neurological system. Depending on the quantity and frequency of drinking, alcohol's effects on the brain can range from minor disturbances in judgment and coordination to more serious consequences including loss of consciousness and, in the worst circumstances, death.

Long-term changes in brain structure and function, such as cognitive impairment and a higher chance of developing specific neurological and mental illnesses, can also result from chronic alcohol consumption.

Once alcohol is in the bloodstream it will reach the brain in a few seconds to minutes, depending on various factors such as the amount and concentration of alcohol consumed, body weight, metabolism, and other individual factors.

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Answer:

Individuals make up a population; populations make up a species; multiple species and their interactions make up a community; and multiple species and their interactions make up ecosystems when you include the abiotic factors.

Answer:

a group of individuals or people make up a community as they live in a certain area

The solution, which is closest to option 4, is 7.816 x 10²⁴ atoms of ions.

An atom can generate a positive charge or a negative charge depending on whether the number of electrons in the atom is greater or fewer than the number of protons in the atom. When one atom is drawn to another atom as a result of an imbalance in the numbers of its electrons and protons, it is referred to as an ION.

We must first figure out how many moles of iron there are in 363 g of iron fillings in order to answer this problem. The formula is as follows:

number of moles=mass/molar mass

The molar mass of iron (Fe) is 55.85 g/mol. Therefore:

number of moles of iron = 363 g / 55.85 g/mol = 6.499 mol

363 g of iron fillings have the following amount of iron ions in total:

total number of iron ions = 2 x number of moles of iron

= 2 x 6.499 mol

= 12.998 mol

The number of moles of iron ions can be converted to the overall amount of iron ions using Avogadro's number (6.022 x 10²³ ions/mol) as follows:

total number of iron ions

= 12.998 mol x 6.022 x 10²³ ions/mol

= 7.816 x 10²⁴ ions

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1. Its renewable nature,

2. Its potential to reduce greenhouse gas emissions and dependence on fossil fuels, and

3. Its ability to provide local sources of energy.

1. The high cost of production and transportation

2. The potential for deforestation and habitat loss

3. The release of pollutants and greenhouse gases during combustion

1. its low emissions and high efficiency,

2. its reliability and consistency,  

3. its potential for use in remote areas.

1. the high upfront cost of installation,

2. the potential for depletion of geothermal reservoirs,

3. the risk of earthquakes and other geological hazards.

The history of hydroelectric power dates back to the 19th century, with the development of water turbines and generators. The first hydroelectric power plant was built in Appleton, Wisconsin in 1882, by a man named H.J. Rogers.

However, the concept of using water to produce mechanical power had been around for centuries. In ancient times, waterwheels were used to power mills and other machinery, and in the Middle Ages, water power was used to operate various devices, such as water pumps, sawmills, and hammers.

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Answer:

Nitrogen liquefies at -195.8°C at room temperature.

At -182.95°C, the periodic table equivalent (oxygen) boils.

The boiling point of nitrogen is lower because there are fewer interactions between nitrogen molecules (N2).

The degree of electron fluctuation within a molecule affects interactions between non-polar molecules.

Van der Waals forces are the oldest sort of intermolecular contact, named after Dutch chemist Johannes van der Waals.

The Van der Waals forces, which include dipole-dipole and dispersion forces, are the weakest intermolecular forces.

Answer:

What paper

Explanation:

What do you mean by paper is too much fir you that paper do youneed help with that paper sir i gotchu withthat paper

Mr Clink has the genotype IOIO

Mrs Clink has genotype IOIA

The child can not belong to them because the IAIB genotype is not in the Punnet square shown

Genotype refers to the genetic makeup of an organism, specifically the combination of alleles (different versions of genes) inherited from its parents. It determines the traits that an organism will express, including physical characteristics, behavioral traits, and susceptibility to certain diseases.

The mother's genotype in question 2 is IOIO

The father's genotype is IAIB

The baby belongs to them because it is possible from the Punnet square shown

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a) 16.5 moles of H3PO4 would react with 1834.67 grams of Ca(OH)2. b) 5.06 x 1024 molecules of Ca(OH)₂ would produce 1.68 moles of H2O. c) 31.5 liters of Ca₃(PO₄)₂ are present if there are 4.2 moles of water produced.

A mole is a unit of measurement used in chemistry to express the amount of a substance. It is defined as the amount of a substance that contains the same number of particles (such as atoms, molecules, or ions) as there are atoms in exactly 12 grams of carbon-12. This number is known as Avogadro's number and is approximately 6.022 x 10^23 particles per mole.

a) The balanced chemical equation for the reaction is:

2 H₃PO₄ + 3 Ca(OH)₂ → Ca₃(PO4)₂ + 6 H₂O

According to the equation, 2 moles of H₃PO₄ react with 3 moles of Ca(OH)₂ to produce 1 mole of Ca₃(PO4)₂ and 6 moles of H2O.

Therefore, the number of moles of Ca(OH)₂ required to react with 16.5 moles of H₃PO₄ can be calculated as:

(16.5 mol H₃PO₄) x (3 mol Ca(OH)₂ / 2 mol H₃PO₄) = 24.75 mol Ca(OH)₂

The molar mass of Ca(OH)₂ is 74.09 g/mol. Therefore, the mass of Ca(OH)₂ required can be calculated as:

24.75 mol x 74.09 g/mol = 1834.67 g

Therefore, 16.5 moles of H₃PO₄ would react with 1834.67 grams of Ca(OH)₂.

b) The balanced chemical equation shows that 3 moles of Ca(OH)₂ react to produce 6 moles of H₂O. This means that 1 mole of Ca(OH)₂ produces 2 moles of H₂O.

The number of moles of H₂O produced by 5.06 x 1024 molecules of Ca(OH)₂ can be calculated as:

5.06 x 1024 molecules Ca(OH)₂ x (1 mol Ca(OH)₂ / 6.022 x 1023 molecules) x (2 mol H2O / 1 mol Ca(OH)₂) = 1.68 mol H₂O

Therefore, 5.06 x 1024 molecules of Ca(OH)₂ would produce 1.68 moles of H2O.

c) From the balanced chemical equation, we know that 3 moles of Ca(OH)₂ react to produce 1 mole of Ca₃(PO4)₂ and 6 moles of H₂O. Therefore, the number of moles of Ca₃(PO4)₂ produced can be calculated as:

3 mol Ca(OH)₂ → 1 mol Ca₃(PO4)₂

If 6 moles of H₂O are produced, then the number of moles of Ca₃(PO₄)₂ can be calculated as:

6 mol H₂O x (1 mol Ca₃(PO₄)₂ / 3 mol Ca(OH)₂) = 2 mol Ca₃(PO₄)₂

Therefore, 4.2 moles of water would be produced from 4.2 / 6 x 2 = 1.4 moles of Ca(OH)₂. The volume of 1.4 moles of Ca₃(PO4)₂ can be calculated using the ideal gas law:

PV = nRT

Assuming standard temperature and pressure (STP), where T = 273 K and P = 1 atm, we can calculate the volume (V) of 1.4 moles of Ca₃(PO4)₂ as:

V = nRT/P = (1.4 mol)(0.0821 L·atm/mol·K)(273 K)/(1 atm) = 31.5 L

Therefore, 31.5 liters of Ca₃(PO4)₂ are present if there are 4.2 moles of water produced.

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A) To determine how many grams of calcium hydroxide would react with 16.5 moles of phosphoric acid, we need to use the stoichiometry of the balanced chemical equation.

From the equation, we can see that 2 moles of H3PO4 react with 3 moles of Ca(OH)2. Therefore, 16.5 moles of H3PO4 will react with (16.5/2) x (3/1) = 24.75 moles of Ca(OH)2. The molar mass of Ca(OH)2 is 74.09 g/mol, so 24.75 moles of Ca(OH)2 is equal to 24.75 x 74.09 = 1835.98 grams of Ca(OH)2. Therefore, 16.5 moles of phosphoric acid would react with 1835.98 grams of calcium hydroxide.

B) The chemical equation shows that 3 moles of Ca(OH)2 react with 6 moles of H2O. Therefore, 1 mole of Ca(OH)2 will produce 2 moles of H2O. Avogadro's number tells us that there are 6.022 x 10²³ molecules in one mole of a substance.

Therefore, 5.06 x 10²⁴ molecules of Ca(OH)2 is equal to 5.06 x 10²⁴/6.022 x 10²³ = 8.4 moles of Ca(OH)2. Each mole of Ca(OH)2 will produce 2 moles of H2O, so 8.4 moles of Ca(OH)2 will produce 2 x 8.4 = 16.8 moles of H2O.

C) The balanced chemical equation shows that 3 moles of Ca(OH)2 react with 1 mole of Ca3(PO4)2. Therefore, 24.75 moles of Ca(OH)2 (calculated in part a) will react with (24.75/3) = 8.25 moles of Ca3(PO4)2. According to the chemical equation, 6 moles of H2O are produced for every 3 moles of Ca(OH)2 consumed. Therefore, 24.75 moles of Ca(OH)2 will produce (24.75 x 6)/3 = 49.5 moles of H2O.

We are given that there are 4.2 moles of water present, so using the ratio from the balanced chemical equation, we can determine that there are (8.25/49.5) x 4.2 = 0.7 moles of Ca3(PO4)2. To convert this to liters, we need to use the molar volume of a gas at standard temperature and pressure, which is 22.4 L/mol. Therefore, the volume of Ca3(PO4)2 present is 0.7 x 22.4 = 15.68 L.

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Explanation:nthere is your work

The mole ratio of C3H6O₂ to CO₂ ia 1:y.

To determine the mole ratio of C3H6O2 to CO2, we need to look at the balanced chemical equation that relates these two substances in a chemical reaction. Let's assume the balanced chemical equation is:

C3H6O2 + xO2 → yCO2 + zH2O

where x, y, and z are coefficients that balance the equation. The mole ratio of C3H6O2 to CO2 is simply the ratio of the coefficients in front of each substance in the balanced equation. From the equation above, we can see that the coefficient in front of C3H6O2 is 1 and the coefficient in front of CO2 is y. Therefore, the mole ratio of C3H6O2 to CO2 is:

1 : y

where y is the coefficient in front of CO2 in the balanced equation.

Since we don't know the exact balanced chemical equation, we cannot determine the value of y and therefore cannot simplify the ratio any further. So the mole ratio of C3H6O2 to CO2 is 1 : y, where y is an unknown integer.

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The acid should be handled with great care  because Acids are highly corrosive in nature. Splashing of acid on our skin can cause severe burns and irritation in the skin. Therefore, we should be careful while handling acids.

An acid is a type of chemical substance that donates positively charged hydrogen ions (H+) to other substances, typically in a chemical reaction. Acids are defined as substances that have a pH value of less than 7 on the pH scale, which measures the acidity or alkalinity of a solution. The lower the pH value, the more acidic the substance is.

Some common examples of acids include hydrochloric acid (HCl), sulfuric acid (H2SO4), and acetic acid (CH3COOH). Acids can be found in a wide range of natural and synthetic substances, including citrus fruits, vinegar, and battery acid. They can be corrosive and dangerous if not handled properly.

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Answer:  Li is the one in excess; 22.81 g Li

Explanation:

First it forms lithium bromide

2 Li  +   Br2 --> 2LiBr

25 g Br2/160 g Br2 X (2moles Li /1mole Br2 ) X (7grams Li/1mole Li) = 2.19 g Li

25 g Li x ( 1mole Li/7 g Li) X ( 1 mole Br2/2 mole Li) x( 160 g Br2 / 1 mole Br2) = 285. 71 g Br2

Now you subtract starting with number given

so 25 g Li - 2.19 g Li = =22.81 g Li

25 g Br2 - 285.71 g Br2 = -260.71 g Br2  (negative means its the limiting reactant.  + means its the one in excess)

Answer:

Explanation:

Part A

Density equals mass divided by volume. The units for density are g/cm³ or g/mL. Note that 1 cm³ = 1 mL.

d = m/v

Substitute the mass and the volume into the equation and then divide the bottom number into the top number.

d = 7.9 g/4.3 cm³ = 1.8 g/cm³

Part B

The density of a substance can be used as a conversion factor to find either the mass of the substance or the volume of the substance.

5 cm³ x 8.9 g/cm³ = 45 g

Note that cm³ units cancel and you are left with grams.

Part C

We will use the density of the substance to find the volume of the substance.

150 g x 1 mL/1.25 g = 120 mL

Note that you can invert density so the units of g cancel and you are left with mL.

Answer:

24.31 g/mol.

Explanation:

moles =mass/molar mass

n=w/m

To solve for Δ2, we need to reverse the reaction and change the sign of Δ1:

2Al2O3(s)⟶4Al(s)+3O2(g)Δ2 = -Δ1

Therefore, Δ2 = -Δ1.

To solve for Δ3, we need to add the reactions for the formation of two moles of Al2O3 from aluminum and oxygen:

4Al(s)+3O2(g)⟶2Al2O3(s)Δ1

2Al2O3(s)⟶4Al(s)+3O2(g)Δ3

Adding these equations gives:

12Al(s)+9O2(g)⟶6Al2O3(s)Δ3

Therefore, Δ3 = 2Δ1.

To solve for Δ4, we need to divide the reaction for the formation of two moles of Al2O3 by two:

2Al(s)+3O2(g)⟶Al2O3(s)Δ1/2

Multiplying this equation by 16 gives:

32Al(s)+48O2(g)⟶16Al2O3(s)8Δ1/2

We can then cancel out the formation of 14 moles of Al2O3:

2Al(s)+32O2(g)⟶Al2O3(s)Δ4 = 8Δ1/2 - 7Δ1

Therefore, Δ4 = 8Δ1/2 - 7Δ1.

Answer:

4 millllllermeeters jb

Answer:

Explanation:

I. A scientist cannot receive credit for another scientist's work simply by reviewing it. Credit is given only to the person or team that did the research.

II. Reviewing scientific results is a crucial step in the scientific process to ensure that the results are accurate and reliable.

III. While reviewing scientific results can help ensure objectivity in the research process, it is not the main purpose of scientific review.

IV. Reviewing scientific results can lead to new and important questions, as well as identify areas for future research.

Therefore, options I and III are incorrect and option B is the best answer.

Answer:

The correct answer is B. II and IV only.

Explanation:

Explanation:

I. A scientist cannot receive credit for another scientist's work simply by reviewing it. Therefore, this option is incorrect.

II. Reviewing scientific results helps to ensure that the results are accurate. This is one of the most important reasons for reviewing scientific work, as it helps to maintain the integrity and credibility of scientific research.

III. Reviewing scientific results does not necessarily help to ensure that scientists are objective when they perform experiments. Therefore, this option is incorrect.

IV. Sometimes additional important questions can be raised when a scientist's work is reviewed. This is another important reason for reviewing scientific work, as it can help to stimulate new ideas and research directions.

Therefore, the only options that are valid are II and IV.