Which of the following statements provides the BEST explanation for the many chemical similarities between two elements in a Main Group? (Note: only ONE answer here.!) (a) They have similar atomic mass values. (b) Both have the same number of valence electrons. (c) They have the same number of protons. (d) They are in the same period.

Ummmmmm......... Ooook then........

Answer: yes Of course

the answer is,

C. The water strider will have more difficulty moving its feet because they will be more strongly attracted to the water.

Answer:

the answer is D. edg. 2020

Explanation:

(a) 0.0080 M/s

(b) 0.0020 M/s

(c) 0.0640 M/s

I hope this helps. :)

Final answer:

Doubling the concentration of CH₃Br or NaOH doubles the rate of the second-order reaction. Halving the concentration of NaOH halves the rate. Increasing both concentrations by a factor of six increases the rate by a factor of thirty-six.

Explanation:

The given reaction CH₃Br + NaOH -> CH₃OH + NaBr is a second-order reaction where the rate of the reaction is directly proportional to the concentrations of both CH₃Br and NaOH. Based on the information provided, if the concentration of one reactant is doubled, the rate of the reaction is also doubled. Similarly, if both concentrations are doubled, the reaction rate increases by a factor of four.

Answer: The accurate formula is [tex]Na_2O[/tex].

Explanation: Atomic no of Sodium is 11. The electronic configuration is:

Na: [tex]1s^22s^22p^63s^1[/tex]

Atomic no of Oxygen is 8. The electronic configuration is:

O: [tex]1s^22s^22p^4[/tex]

Thus sodium needs to lose one electron in order to attain noble gas configuration and Oxygen needs to gain two electrons to attain noble gas configuration.

Thus Na will lose one electron to form [tex]Na^+[/tex] and Oxygen gain two electrons to form [tex]O^{2-}[/tex]. In order to form a stable neutral compound, two sodium ions are required.

Thus the formula will be [tex]Na_2O[/tex].

The study of chemicals is called chemistry. There are two types of solution in the chemistry and these are acid and base.

The correct answer is [tex]Na_2O[/tex]

What are moles?

Thus sodium needs to lose one electron in order to attain noble gas configuration and Oxygen needs to gain two electrons to attain noble gas configuration.

Thus Na will lose one electron to form [tex]Na^+[/tex] and Oxygen gain two electrons to form[tex]O^{-2}[/tex] In order to form a stable neutral compound, two sodium ions are required.

Thus the formula will be [tex]Na_2O[/tex].

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Balanced chemical reaction:

4C₅H₉O + 27O₂ → 20CO₂ + 18H₂O.

According to principle of mass conservation, number of atoms must be equal on both side of chemical reaction.

Type of reaction is combustion.

Combustion is reaction with oxygen.

Organic compound reacts with oxygen and produce carbon dioxide and water.

B. Earths Moon is the answer.

Hope it helped!

b. earth's moon  is the only object out of the four that is visible only by reflection.

The sun is a source of heat and light.

Although the moon can be seen at night and seems to glow, it is only reflecting light emitted from the sun.

A candle flame, similar to the sun, is a source of light and heat.

A bolt of lightning also emits light, so it is not the correct answer.

According to first law of thermodynamics, energy can neither be formed nor be destroyed but can be converted from one form to another.

thus the statement that Energy can be transferred or transformed inside or outside of a system, but energy cannot be destroyed, is true statment.

Answer:

Energy can be transferred or transformed inside or outside of a system, but energy cannot be destroyed.

Explanation:

A popular principle in science is known as the principle of conservation of energy. It states that energy cannot be created nor destroyed but can be converted from one form to another.

In a system, energy transformations are possible and does happen though inefficiently according to the laws of thermodynamics but energy can never be destroyed following the laws of thermodynamics.

Xenon atoms occupy about 27.5% of the total volume in a sample of xenon gas at STP due to their packing.

To calculate the fraction of space that xenon (Xe) atoms occupy in a sample of xenon at Standard Temperature and Pressure (STP), we can use the concept of the packing fraction.

This fraction represents the volume occupied by the Xe atoms compared to the total volume of the sample.

1. Calculate the volume of one xenon atom:

  Given the atomic radius (r) of xenon as 1.3 angstroms, we need to find the volume of a single Xe atom. The formula for the volume of a sphere is [tex]V = (4/3)\pi r^3[/tex], where r is the radius.

2. Calculate the volume occupied by one mole of Xe atoms:

3. Convert the volume to liters:

4. Calculate the total volume of one mole of Xe gas at STP:

5. Calculate the packing fraction:

Therefore, xenon atoms occupy approximately 27.5% of the total volume in a sample of xenon gas at STP.

Answer:

Gallium

Explanation:

Propyne is an unsaturated hydrocarbon because it contains a carbon-to-carbon triple bond, distinguishing it from saturated hydrocarbons like Methane and Nonane, which only contain single bonds.

In Chemistry, hydrocarbons are organic compounds consisting entirely of hydrogen and carbon. They are classified into two main types: saturated and unsaturated hydrocarbons. Saturated hydrocarbons have all single bonds and are fully saturated with hydrogen. Unsaturated hydrocarbons contain one or more carbon-to-carbon double or triple bonds.

A is the correct answer. Propyne is an unsaturated hydrocarbon because it contains a triple bond between two carbon atoms. On the other hand, Methane and Nonane are saturated hydrocarbons because they only have single bonds connecting their carbon and hydrogen atoms. Methyl is a part of many hydrocarbons but itself is not a complete hydrocarbon.

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(Answer) (C) 3

Boron is a non-metal with atomic number 5. The electronic configuration of boron atom is [He]2s^22p^1.

Boron atom has the tendency to obtain stable electronic configuration like its nearest noble gas helium by losing electrons. Boron atom usually loses 3 electrons from its outermost electronic shell to form a cation with +3 charge.

Therefore, boron atom loses 3 electrons while forming an ion.

Answer is: D. sodium and sulfur.

When the electronegativity difference is greater, the bond polarity is increasing..  

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.  

Atoms with higher electronegativity attracts more electrons towards it, electrons are closer to that atom.  

Δχ(Na-S) = 2.6 - 0.95 = 1.655; electronegativity difference between sodium and sulfur.

Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).

Sodium is metal (forms cation) and sulfur is nonmetal (forms anion).

So the equation is,

2Cl2(g) + 7O2(g) + 130kcal -> 2Cl2O7(g)

from this , ΔH°rxn=[tex]130kcal.mol^{-1}[/tex]

[tex]mol^{-1}[/tex] is mentioned because it is for per mole of reaction. So for 4. moles of the product [tex]2Cl_{2} O_{7}[/tex] we need 4/2 moles of reaction to be used to calculate associated enthalphy change for the reaction.

Therefore[tex]4/2*130=260 kcal[/tex]

Answer is: B) Wind produced by the uneven heating of Earth's surface.

Gasoline is a mixture  of many different hydrocarbons: alkanes (paraffins), cycloalkanes and alkenes (olefins). It is not renewable resource, because every year is less and less gasoline.

Natural gas is usualy methane, it is not renewable recourse.

Wind consists of the bulk movement of air.

Final answer:

Wind produced by the uneven heating of Earth's surface is the renewable resource among the options provided.

Explanation:

Among the listed options, the renewable resource is B) Wind produced by the uneven heating of Earth's surface. Renewable energy sources such as wind can be replenished within a human timescale and do not deplete. Gasoline, even if it contains some alcohol, is not renewable because it is derived from petroleum which is a finite resource. Natural gas, while it may be used alongside renewable resources, is also non-renewable as it cannot be replenished within a human timescale once it's extracted from deep underground.

Answer: The bond formed between the elements will be ionic bond.

Explanation: We are given two elements having electronic configurations:

Element 1: [tex]1s^22s^1[/tex]

Element 2: [tex]1s^22s^22p^5[/tex]

Element 1 can easily loose 1 electron to attain stable electronic configuration and Element 2 can accept 1 electron to attain stable electronic configuration.

For these elements, there will be a complete transfer of electron from Element 1 to Element 2. Hence, this will form a ionic bond.

From the configuration, Element 1 is Lithium and Element 2 is Fluoride. So, the compound is LiF.

The atoms with the electron configurations of Lithium (1s2 2s1) and Fluorine (1s2 2s2 2p5) predominantly form an ionic bond as Lithium loses an electron and Fluorine gains that electron.

When determining the bond formed between atoms, it helps to refer to their electron configuration. The electron configurations you provided correspond to Lithium (1s2 2s1) and Fluorine (1s2 2s2 2p5).

Lithium, being a member of Group 1, is an alkali metal and tends to lose its single 2s electron to achieve a stable noble gas configuration. Fluorine, a member of Group 17 (halogens), is eager to gain an electron to achieve the stable electron configuration of noble gases as well. This exchange of electrons results in the formation of an ionic bond predominantly.

There are also covalent bonds which result from the sharing of electrons, seen in molecules where both atoms have similar electronegativities (the ability of an atom to attract shared electrons). The most common types being sigma (σ) bonds and pi (π) bonds. Sigma bonds result from the end-to-end overlapping of atomic orbitals and are the strongest type of covalent bond. Pi bonds, on the other hand, form from the side-by-side overlap of atomic orbitals and are generally weaker than sigma bonds.

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The mass of water required to absorb 5.23 × 10⁴ kJ of energy during boiling is approximately 23.2 kg.

To find the mass of liquid water required to absorb a specific amount of energy during boiling, one can use the formula Qv = mLv, where Qv is the energy (in this case 5.23 × 10⁴ kJ), m is the mass we need to find, and Lv is the latent heat of vaporization, which for water is 2256kJ/kg.

Rearranging the formula to get mass, we find m = Qv/Lv. We substitute given values and calculate the mass.

So, m = (5.23 × 10⁴ kJ) / (2256 kJ/kg) = 23.2 kg (approximately).

This means that approximately 23.2 kg of water is required to absorb 5.23 × 10⁴ kJ of energy on boiling.

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The mass of liquid water required to absorb 5.23 × 10⁴ kJ of energy on boiling is approximately 23.14 kg.

The latent heat of vaporization of water is approximately 2260 kJ/kg.

The formula to calculate the mass (m) of the water is:

[tex]\[ Q = m \times L \][/tex]

where:

- Q is the amount of energy absorbed (in kJ),

- m is the mass of the water (in kg),

- L is the latent heat of vaporization (in kJ/kg).

Given:

[tex]\[ Q = 5.23 \times 10^4 \text{ kJ} \]\[ L = 2260 \text{ kJ/kg} \][/tex]

We need to find m.

Rearranging the formula to solve for m:

[tex]\[ m = \frac{Q}{L} \][/tex]

Substitute the given values:

[tex]\[ m = \frac{5.23 \times 10^4 \text{ kJ}}{2260 \text{ kJ/kg}} \][/tex]

Perform the calculation:

[tex]\[ m = \frac{52300 \text{ kJ}}{2260 \text{ kJ/kg}} \]\[ m \approx 23.14 \text{ kg} \][/tex]

If a neutral atom loses electrons, type of particle which  is formed is a positively charged ion.

An ion is defined as an atom or a molecule which has a net electrical charge. There are 2 types of ions :1) cation 2) anion . The cation is the positively charged ion and anion is the negatively charged ion . As they are oppositely charged they attract each resulting in the formation of ionic bond.

Ions consisting of single atom are mono-atomic ions while which consists of two or more ions are called as poly-atomic ions . They are created by chemical interactions . They are very reactive in their gaseous state and rapidly react with oppositely charged ions resulting in neutral molecules.

Ions combine which are of opposite charges to form an ionic compound which are hard and good conductors of electricity.

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The frequency of radio waves at the two stations are:

1. WIL-92.3 : Frequency = 92.3 MHz (mega hertz)

2. KSHE-94.7 : Frequency = 94.7 MHz

The wavelength (λ) and frequency (ν) are related as:

ν = c/λ ------(1)

Energy (E), frequency (ν) and wavelength (λ) are related as:

E = hν -----(2)

(or)

E = hc/λ ----(3)

A) Based on equation (2), higher the frequency higher is the energy. Therefore, station KSHE broadcasts waves with higher energy

B) Based on equation (1), higher the frequency lower will be the wavelength. Station KSHE will broadcast waves with shorter wavelength

C) KSHE will broadcast waves with higher frequency

Station KSHE-94.7 broadcasts waves with more energy, a shorter wavelength, and a higher frequency compared to WIL-92.3, as higher frequencies correspond to more energy and shorter wavelengths.

In comparing radio wave broadcasts of WIL-92.3 and KSHE-94.7, we need to consider frequency, energy, and wavelength properties of radio waves. Here is how they relate:

Given that,:

Therefore, all the three properties are higher for KSHE-94.7 as compared to WIL-92.3.

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The lowest layer of Earth's atmosphere is called troposphere.The layer immediately next to troposphere is called Stratosphere. The boundary layer between troposphere and stratosphere is described as tropopause.

The tropopause is the transition layer between the troposphere and the stratosphere in Earth's atmosphere. It is located at an altitude of about 12-15 km, and it is the coldest part of the atmosphere.

The tropopause can be defined as the transition layer between the troposphere and the stratosphere in Earth's atmosphere. It is located at an altitude of about 12-15 km (7-8 miles), and it is the coldest part of the atmosphere. The temperature in the troposphere decreases steadily with increasing altitude, but at the tropopause, the temperature starts warming again due to the absorption of UV radiation by ozone in the stratosphere.

Answer is: the two electrons in the fourth shell.

Atomic number of calcium is 20, it means that it has 20 protons and 20 electrons, so atom of calcium is neutral.  

Electron configuration of calcium atom: ₂₀Ca 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²; calcium has two valence electrons (4s²).  

In reactions it lose those two electrons ang form cation with positive charge 2+.

Atomic number is the number of protons, which is characteristic of a chemical element.

Beryllium, magnesium,calcium and strontium are alkaline earth metals. The elements have very similar properties.

Alkaline earth metals have in common an outer s- electron shell (two electrons).

Your answer is A

6.02 × 1023 particles

Answer: [tex]6.022\times 10^{23}[/tex]

Explanation: According to Avogadros law, one mole of any substance contains a fixed number of particles i.e [tex]6.022\times 10^{23}[/tex] particles (atoms, molecules or ions) which is also known by the name Avogadro's number.

For example: 1 mole of [tex]O_2[/tex] molecule contains [tex]6.022\times 10^{23}[/tex] molecules of oxygen.

1 mole of [tex]He[/tex] contains [tex]6.022\times 10^{23}[/tex] atoms of helium.

1) Answer is: the oxidation number of manganese in MnO₄⁻ is +7.

Permanganate anion has negative charge 1-.

Oxygen (O) in permanganate anion has oxidation number -2.

x + 4 · (-2) = -1.

x - 8 = -1.

x = +7; oxidation nzmber of manganese.

Oxidation number shows the degree of oxidation of an atom in a chemical compound.

2) Answer is: Zn + Cu2+ → Zn2+ + Cu.

In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).

Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.

Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.

In other chemical reactions, there is no change of oxidation number of elements.

3) Answer is: Br2 is the oxidizing agent because its oxidation number decreases.

Balanced chemical reaction: 2Al + 3Br₂ → 2AlBr₃.

In this chemical reaction, aluminium change oxidation number from 0 to +3 (lose electrons) and bromine change oxidation number from 0 to -1 (gain electrons, reduced).

Oxidizing agent is a substance that has the ability to oxidize other substances, to cause them to lose electrons.

In oxido-reduction reaction, at least one element lose and one element gain electrons.

4) Answer is: Br2 + 2Cl− → Cl2 + 2Br⁻.

Oxidation is increase of oxidation number.

In this balanced chemical reaction, chlorine change oxidation number from -1 (Cl⁻) to oxidation number 0 (Cl₂).

Oxidation half reaction: 2Cl⁻ → Cl₂⁰ + 2e⁻.

Reduction half reaction: Br₂ + 2e⁻ → 2Br⁻.

In other chemical reactions, chlorine is reduced.

5) Answer is: Observation 1 is a result of copper ions moving into the solution.

The reactivity series is a series of metals from highest to lowest reactivity. Metal higher in the reactivity series will displace another.

Copper (Cu) is higher in activity series than silver (Ag), so copper lose electron and silver gain electrons.

Copper is oxidized (increase of oxidation number) and silver is reduced.

The oxidation number of manganese in MnO4− is +7. A reaction that can power a battery is Zn + Cu2+ → Zn2+ + Cu. Chlorine is oxidized in the reaction 2ClO3− + 12H+ → Cl2 + 6H2O, and observation 1 in an experiment with copper and silver nitrate indicates copper ions moving into the solution.

The oxidation number of manganese in MnO4− is +7. In this compound, oxygen has a typical oxidation state of -2, and because the compound has an overall charge of -1, the oxidation number of manganese can be calculated using the equation: Mn + 4(×-2) = -1, which gives Mn a oxidation state of +7.

The reaction that could be used to power a battery is Zn + Cu2+ → Zn2+ + Cu. In this redox reaction, zinc is oxidized, going from Zn to Zn2+, and copper is reduced, going from Cu2+ to Cu, allowing for the transfer of electrons necessary to generate electric current.

The oxidizing agent in the reaction 2Al + 3Br2 → 2AlBr3 is Br2, because it is reduced, with its oxidation number decreasing from 0 in Br2 to -1 in AlBr3.

Chlorine (Cl) is oxidized in the reaction 2ClO3− + 12H+ → Cl2 + 6H2O. Here, the chlorine goes from an oxidation state of +5 in ClO3− to 0 in Cl2.

The correct explanation for one of the observations in the experiment with the silver nitrate solution and the copper strip is that Observation 1 is a result of copper ions moving into the solution. When the copper strip is placed in the silver nitrate solution, it undergoes oxidation, and Cu atoms lose electrons to form Cu2+ ions, which then cause the solution to turn blue.

Another way static electricity can build up in an object is induction. Induction is the transfer of electrons from one part of an object to another part, caused by the electric field of another object, without the two objects touching.

  The empirical   formula  of hydrocarbon is C₃H₈

The  molecular formula of hydrocarbon   is C₆H₁₆

Empirical  formula  calculation

Hydrocarbon  contain  carbon and hydrogen

  Step 1:  find the  mass  carbon (C) in carbon dioxide (CO₂)  and hydrogen (H )  in water

mass of  of element = molar mass  of element/ molar mass molecule x total mass of    molecule

From periodic table the molar mass  of C =12,    for CO₂ = 12+( 16 x2) =44 g/mol,     for H = 1.00 g/mol,    for H₂O = (2 x1)+16 = 18 g/mol

mass of C = 12/44 x 2.641 =0.7203 g

since there are 2 atom  of H in H₂O the molar mass of H = 1 x2 = 2 g/mol

mass of H  is therefore =  2/18 x 1.442 =0.1602 g

Step 2:  find the moles of C and H

moles = mass÷ molar mass

moles of C = 0.7203 g÷ 12 g/mol = 0.060  moles

moles of H  =  0.1602÷ 1 g/mol = 0.1602 moles

Step 3: find the mole ratio  of C and H by dividing  each  mole by smallest mole ( 0.06)

for C = 0.06/0.06 =1

  For H = 0.1602/0.06 =2.67

multiply   by 3  to remove the decimal

For C = 1 x3 =3

For H = 2.67 x3 =8

therefore the empirical formula = C₃H₈

The molecular formula calculation

[C₃H₈]n  = 88.1 g/mol

[12 x 3)+( 1 x8)]n =88.1 g/mol

44 n = 88.1

divide both side by 44

n=2

therefore [C₃H₈]₂   = C₆H₁₆

1) Answer is: the empirical formula of the hydrocarbon is C₃H₈.

Chemical reaction: CₓHₐ + O₂ → xC + a/2H₂O.

m(CO₂) = 2.641 g.; mass of carbon dioxide.

n(CO₂) = m(CO₂) ÷ M(CO₂).

n(CO₂) = 2.641 g ÷ 44.01 g/mol.

n(CO₂) = n(C) = 0.06 mol; amount of carbon.

m(H₂O) = 1.442 g.

n(H₂O) = 1.442 g ÷ 18 g/mol.

n(H₂O) = 0.08 mol.

n(H) = 2 · n(H₂O) = 0.16 mol; amount of hydrogen.

n(C) : n(H) = 0.06 mol : 0.16 mol /0.06 mol.

n(C) : n(H) = 1 : 2. 67 /×3.

n(C) : n(H) = 3 : 8.

2) Answer is: the molecular formula of hydrocarbon is C₆H₁₆.

M(C₃H₈) = 44.05 g/mol; molar mass of empirical formula.

M(CₓHₐ) = 88.1 g/mol; molar mass of hydrocarbon.

M(CₓHₐ) ÷ M(C₃H₈) = 88.1 g/mol ÷ 44.05 g/mol.

M(CₓHₐ) ÷ M(C₃H₈) = 2.

The molar mass of hydrocarbon is two times higher than molar mass of empirical formula, so number of carbon atoms is six and number of hydrogen atoms sixteen.

The enthalpy of combustion of magnesium in this experiment is approximately -602 kJ/mol, which was determined by dividing the total heat transferred (calculated from the calorimeter's heat capacity and temperature change) by the number of moles of magnesium burnt.

In the experiment described, a small piece of magnesium was burnt in a oxygen bomb calorimeter, leading to a recorded temperature rise in the calorimeter and the water it contains. The enthalpy of combustion of magnesium can be determined from these values by using the equation q = mcΔT, where q is the heat transferred, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature. In this case, the total heat transferred (q) is the heat capacity of the calorimeter and the water times the temperature change, or 5760 J/°C * 0.570 °C = 3283.2 J. The molar enthalpy of combustion can then be calculated by determining the moles of Mg burnt (0.1326 g / 24.305 g/mol = 0.00545 mol) and dividing the heat produced by the moles of Mg burnt (3283.2 J / 0.00545 mol = -602 kJ/mol). Therefore, when rounded to 3 significant figures, the enthalpy of combustion of magnesium is around -602 kJ/mol.

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Answer:

This reaction is exothermic because the system shifted to the right on cooling.  

Step-by-step explanation:

 2NO₂   ⇌   N₂O₄

brown    colourless

According to Le Châtelier's Principle, when a stress is applied to a system at equilibrium, the system will respond in a way that tends to relieve the stress.

You applied a stress by cooling the system (removing heat). The system responded by moving in a direction that created more heat.

The mixture became lighter brown on cooling, so the position of equilibrium must have shifted to the right to generate the heat.

The reaction is exothermic.

When the light brown color equilibrium mixture was moved from room temperature to a lower temperature, the mixture turned lighter brown in color shows this reaction is exothermic because the system shifted to the right on cooling.

According the the equilibrium law, if any external element is added in the equilibrium state, ten the whole reaction will shifts to that side which reduces the effect of that additional element.

Given chemical reaction is:

2NO₂(g) ⇌ N₂O₄(g)

Where NO₂ shows brown color and N₂O₄ is colorless gas. If we notice a light brown color of the mixture when we moved from room temperature to a lower temperature then the reaction will shifts to the right side and will show exothermic behavior to overcome the external effect.

Hence, option (d) is correct.

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B. Is the Answer 6.022 * 1023

Answer: B) [tex]6.022\times10^{23}[/tex] atoms.

Explanation:

According to the International System of units ,

A mole is basically denotes a unit that contains [tex]6.022\times10^{23}[/tex] of atoms.

It is also known as Avagadro Number.

Similarly,  the number of atoms in one mole of gold = [tex]6.022\times10^{23}[/tex]

hence, the correct answer is B) [tex]6.022\times10^{23}[/tex] atoms.

Final answer:

2.00 g of oxygen is produced ,option B

Explanation:

To determine how many grams of oxygen are produced when 11.5 g of NO2 is formed, we can use the stoichiometry of the balanced chemical equation:

2 Pb(NO3)2(s) = 2 PbO(s) + 4 NO2(g) + O2(g)

From the equation, we see that 4 moles of NO2 are produced alongside 1 mole of O2. First, we find the number of moles of NO2 that 11.5 g corresponds to:

Molar mass of NO2 = 14.01 (N) + (2 *16.00) (O) = 46.01 g/mol

Moles of NO2 = 11.5 g / 46.01 g/mol

Then, we take into account the mole ratio between NO2 and O2, which is 4:1:

Moles of O2 = (Moles of NO2)  times (1 mole O2 / 4 moles NO2)

Finally, we find the mass of O2 produced:

Molar mass of O2 = 2  times 16.00 g/mol = 32.00 g/mol

Mass of O2 = (Moles of O2)  times (32.00 g/mol)

By going through the calculations, we find that the mass of O2 produced is 2.00 g, which corresponds to option (b).