The tyndall effect is used to distinguish between

Answer:

Explanation:

Attractive forces between the gase molecules become significant at lower temperatures

Reason for that is when the temperature of the molecules decrease .the kinetic energy also decreases .at a certain low temperature the gases change into the liquid state . Therefore the attractive forces between these gas molecules become very significant near liquefying temperature . that's why they deviate from their original behavior at low temperature

Real gases deviate from ideal gas behavior primarily due to intermolecular attractions and the volumes of the gas molecules. The effects of these factors are more pronounced at high pressures and low temperatures.

The behavior of real gases deviates from ideal gas behavior due to intermolecular attractions and the finite volume of gas molecules. Attractive forces between molecules have the effect of pulling them closer together, which decreases the pressure or volume. This phenomenon is more pronounced at low temperatures as the lower kinetic energy (KE) at cold temperatures can't overcome these attractions as efficiently.

On the contrary, as the pressure increases the volume of the gas molecules themselves becomes appreciable relative to the total volume occupied by the gas. Therefore, real gases behave more like ideal gases at relatively low pressures and high temperatures, and significant deviations occur at high pressures and low temperatures.

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Answer:

It turns clear phenolphthalein pink.

answer above is for second answer

Explanation:

The statement that is most likely true about HBr is It turns blue litmus red

From the question, we are to determine which statement is most likely true about HBr

HBr is Hydrobromic acid. Since it HBr is an acid, it must have the properties  of an acid

Some of the properties of an acid are

Hence, the statement that is most likely true about HBr is It turns blue litmus red

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These are four questons and four answers:

Answers:

Explanation:

Question 1) Cl₂O₇:

a) Net charge of the compound: 0

b) Rule: oxygen works with oxidation state +2, except with peroxides.

d) Rule: balance of charges: ∑ of the charges = net charge

Call X the oxidation number of Cl:

Conclusion: the oxidation number of Cl in Cl₂O₇ is 7⁺.

Question 2) AlCl₄⁻

a) Net charge of the ion: - 1

b) Rule: common oxidation number of Al in compounds: +3

c) Rule: balance of charges: ∑ charges = net charge = - 1

Conclusion: the oxidation number of Cl in AlCl₄⁻ is 1 ⁻.

Question 3) Ba(ClO₂)₂

a) Net charge of the compound: 0

b) Rule: common oxidation number of BA in compounds: +2

c) Rule: common oxidation number of O in compounds (except in peroxides): -2

d) Rule: balance of charges: ∑ charges = net charge = 0

Conclusion: the oxidation number of Cl in Ba(ClO₂)₂  is 3⁺.

Question 4) CIF₄⁺

a) Net charge of the ion: + 1

b) Rule: common oxidation number of F : - 1 (it is the most electronegative)

c) Rule: balance of charges: ∑ charges = net charge = + 1

Conclusion: the oxidation number of Cl in ClF₄⁺ is 5⁺.

a) (NH4)2SO4 --- 1 mole of it contains 2 moles of N, 8 moles of H, 1 mole of S, and 4 moles of O.

MM = (2 moles N x 14.0 g/mole) + (8 moles H x 1.01 g/mole) + (1 mole S x 32.1 g/mole) + (4 moles O x 16.0 g/mole) = 132 g/mole.

6.60 g (NH4)2SO4 x (1 mole (NH4)2SO4 / 132 g (NH4)2SO4) = 0.0500 moles (NH4)2SO4

b) The molar mass for Ca(OH)2 = 74.0 g/mole, calculated like (NH4)2SO4 above.

4.5 kg Ca(OH)2 x (1000 g / 1 kg) x (1 mole Ca(OH)2 / 74.0 g Ca(OH)2) = 60.8 moles Ca(OH)2

The number of mole in the compounds are:

A. 6.60 g of (NH₄)₂SO₄ contains 0.05 mole.

B. 4.5 kg Ca(OH)₂ contains 60.81 moles

The mole of a substance is related to its mass and molar mass according to the equation:

[tex]Mole = \frac{mass}{molar mass }[/tex]

With the above formula, we can obtain the answer to the questions given above. This is illustrated below:

A. Determination of the number of mole in  6.60 g of (NH₄)₂SO₄

Molar mass of (NH₄)₂SO₄ = 2[14 + (4×1)] + 32 + (4×16)

= 2[14 + 4] + 32 + 64

= 2[18] + 32 + 64

= 36 + 32 + 64

= 132 g/mol

Mass of NH₄)₂SO₄ = 6.60 g

[tex]Mole = \frac{mass}{molar mass }[/tex]

Mole of NH₄)₂SO₄ = [tex]\frac{6.6}{132}\\\\\\[/tex]

Thus, 6.60 g of (NH₄)₂SO₄ contains 0.05 mole.

B. Determination of the number of mole in 4.5 kg Ca(OH)₂

Molar mass of Ca(OH)₂ = 40 + 2(16 + 1)

= 40 + 2(17)

= 40 + 34

= 74 g/mol

Mass of Ca(OH)₂ = 4.5 kg

= 4.5 × 1000

= 4500 g

Mole of Ca(OH)₂ =?

[tex]Mole = \frac{mass}{molar mass }[/tex]

Mole of Ca(OH)₂ = [tex]\frac{4500}{74}\\\\\\[/tex]

Thus, 4.5 kg Ca(OH)₂ contains 60.81 moles

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Answer:

The element is Hafnium

Explanation:

Hi, Hafnium was discovered in 1923 by George Charles de Hevesy y Dirk Coster in Denmark. It's name was given after the capital of that country: Copenhagen which name in latin is Hafnia.

I would use dimensional analysis for this problem. You would start with the given amount of Na which is 59.0g. You are trying to find the moles of NaCl.

(59.0g Na)*(1 mol Na)/(22.99 g Na)*(2 mol NaCl)/(2 mol Na)=

2.57 mol NaCl

The units will cancel out until you are left with moles of NaCl. The answer has the correct number of significant figures (3 sig figs).

Answer: 2.56 moles

Explanation:

To calculate the moles :

[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]    

[tex]\text{Moles of} Na=\frac{59.0g}{23g/mol}=2.56moles[/tex]

[tex]2Na(s)+Cl(g)\rightarrow 2NaCl(s)[/tex]

Na is the limiting reagent as it limits the formation of product and chlorine is the excess reagent.

According to stoichiometry :

2 moles of Na produce = 2 moles of NaCl

Thus 2.56 moles of Na produce =[tex]\frac{2}{2}\times 2.56=2.56moles[/tex]  of NaCl

Thus 2.56 moles of NaCl are produced.

Answer:

3.

Explanation:

Al(OH)₃ + 3 HCl → AlCl₃ + 3H₂O,

It is clear that 1.0 mole of Al(OH)₃ reacts with 3.0 mole of HCl to produce 1.0 mole of AlCl₃ and 3.0 moles of H₂O,

So, the coefficient of HCl is 3.

In a reaction, there is no energy lost or created because of the law of conversion of energy. The energy is just transformed from one form to others.

A chemical reaction is a reaction in which the reactant are combined to form products.

In a chemical reaction, energy does not lose, it is just transformed into another form.

Thus, In a reaction, there is no energy lost or created because of the law of conversion of energy. The energy is just transformed from one form to others.

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Answer:

0.42%

Explanation:

∵ pH = - log[H⁺].

2.72 = - log[H⁺]

∴ [H⁺] = 1.905 x 10⁻³.

∵ [H⁺] = √Ka.C

∴ [H⁺]² = Ka.C

∴ ka = [H⁺]²/C = (1.905 x 10⁻³)²/(0.45) = 8.068 x 10⁻⁶.

∵ Ka = α²C.

Where, α is the degree of dissociation.

∴ α = √(Ka/C) = √(8.065 x 10⁻⁶/0.45) = 4.234 x 10⁻³.

∴ percentage ionization of the acid = α x 100 = (4.233 x 10⁻³)(100) = 0.4233% ≅ 0.42%.

The answer is 0.42% just did it ;)

Answer:

228.6 g of H₂O

Explanation:

the balanced equation for the combustion of methane is as follows

CH₄ + 2O₂ ---> CO₂ + 2H₂O

molar ratio of CH₄ to H₂O is 1:2

when 1 mol of CH₄ reacts with excess O₂, 2 mol of H₂O is formed

therefore when 6.35 mol of CH₄ reacts - 2 x 6.35 mol = 12.7 mol of H₂O is formed

therefore mass of H₂O formed is - 12.7 mol x 18 g/mol = 228.6 g of H₂O is formed

Final answer:

Using the stoichiometry of the balanced chemical equation CH4 + 2O2 → CO2 + 2H2O, 6.35 moles of methane produce 12.7 moles of water, which is equal to 228.854 grams of water.

Explanation:

To find out how many grams of water (H₂O) are produced from the combustion of 6.35 moles of methane (CH₄), we need to use the stoichiometry of the balanced chemical equation, which is CH₄ + 2O₂ → CO₂ + 2H₂O.

According to the equation, each mole of methane produces 2 moles of water. Therefore, 6.35 moles of methane will produce 6.35 * 2 = 12.7 moles of water. The molar mass of water is 18.02 g/mol, so the total mass of water produced is 12.7 moles * 18.02 g/mol = 228.854 g of H₂O.

Answer:

= 6.32 Joules

Explanation:

The heat given off by a substance while changing from liquid state to solid state without change in temperature is given by the formula;

Q = n×Lf

where, Q is the heat quantity, n is the number of moles and Lf is the molar heat of fusion. The methanol HF is 3.16 kJ/mol.

The number of moles = 64 g/32 g/mol

                                   = 2 moles

Therefore;

Heat = 2 moles × 3.16 kJ/mol

        = 6.32 Joules

Answer:

6.32 kJ

Explanation:

took the test

Answer:

The correct answer to your question is:  C

Explanation:

A. The noble gases are very unstable.  This option is wrong because noble gases are the most stable elements.

B. In the world, elements are usually in their pure form.  this option is wrong because most of the elements are part of compounds.

C. Eight electrons in the outer shell is the most stable configuration.  This option is correct, metals and non metals reach stability by gaining or losing electrons to reach electrons

D. A chemical bond is a strong attractive force between atoms. This option is also right, this is a correct definition of chemical bond.

Answer:

You must remove [tex]\text{50.6 kJ}[/tex] .

Explanation:

There are three heat transfers in this process:

Total heat = cool the vapour + condense the vapour + cool the liquid  

       q          =           q₁            +                q₂                   +           q₃

       q          =       nC₁ΔT₁        +          nΔHcond             +        nC₂ΔT₂

Let's calculate these heat transfers separately.

Data:

You don't give "the data below", so I will use my best estimates from the NIST Chemistry WebBook. You can later substitute your own values.

C₁ = specific heat capacity of vapour = 90 J·K⁻¹mol⁻¹

C₂ = specific heat capacity of liquid   = 115 J·K⁻¹mol⁻¹

ΔHcond = -38.56 kJ·mol⁻¹

Tmax = 300   °C

  b.p. =   78.4 °C

Tmin =   25.0 °C

n = 0.782 mol

Calculations:

ΔT₁ = 78.4 - 300 = -221.6 K

q₁ = 0.782 × 90 × (-221.6) = -15 600 J = -15.60 kJ

q₂ = 0.782 × (-38.56) = -30.15 kJ

ΔT = 25.0 - 78.4 = -53.4 K

q₃ = 0.782 × 115 × (-53.4) = -4802 J = 4.802 kJ

q = -15.60 - 53.4 - 4.802 = -50.6 kJ

You must remove [tex]\text{50.6 kJ}[/tex] of heat to convert the vapour to a gas.

To find the total heat needed to convert the gaseous ethanol to liquid, one must first consider the cooling of the gaseous ethanol, then the condensation of the gaseous ethanol, and lastly cooling the liquid ethanol to 25 degrees Celsius. Each step requires a specific calculation, and the final heat value is the sum of all energies calculated in these three steps, with all values converted to the same energy unit for accuracy.

We first need to handle the cooling of the gaseous ethanol. For this, we'll use the specific heat capacity ... Given that the heat capacity (cv) of ethanol is about 75 J/mol*K (approximated because the exact value can vary), the heat loss (q1) could be calculated in this way:

q = cv * n * ΔT = 75J/mol*K * 0.782mol * (300-25)K

Subsequently, for condensation, we'll use the heat of condensation ... Assuming the heat of condensation of ethanol to be around 38.56 kJ/mol (procured from a standard table or book), we get:

q = ΔHvap * n = 38.56 kJ/mol * 0.782 mol

Lastly, we need to consider cooling the liquid ethanol to 25°C ... Therefore, knowing that the specific heat of liquid ethanol is about 112 J/mol*K:

q = c * n * ΔT = 112J/mol*K * 0.782mol * (78.37-25)K

Summing all these energies, then converting to an identical energy unit, gives you the total energy required.

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Withholding personal judgment against people with mental illness is important to understand their troubles objectively and provide support.

The main importance of withholding personal judgment against people with mental illness is that it allows us to attempt to objectively understand a person's troubles. When we withhold personal judgment, we can empathize with individuals suffering from mental illness and provide them with the support and care they need. Additionally, by not judging, we create an environment that encourages open communication and reduces the stigma surrounding mental health.

The reaction between sodium And chlorine yields sodium chloride. Given 500 gms each of sodium and chlorine, approximately 500 g of sodium chloride can be produced.

The reaction 2Na + Cl2 produces sodium chloride or NaCl. To calculate the amount of sodium chloride produced from 500 g of sodium and 500 g of chlorine, we first need to know the molar mass of the elements involved. The molar mass of Sodium (Na) is 23 g/mol and Chlorine (Cl2) is 71 g/mol. Now, from the balanced equation, it is clear that 2 moles of Na (46 g) react with 1 mole of Cl2 (71 g) to produce 2 moles of NaCl, whose molar mass is 58 g/mol. Hence, 117 g of Na would react completely with 500 g of Cl2 to produce 500 g of NaCl approximately, making Sodium (Na) the limiting reactant. Therefore, from 500 g of each Sodium and Chlorine, we could theoretically produce around 500 g of Sodium Chloride (NaCl).

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Final answer:

Using stoichiometry, it is determined that 500 grams of chlorine is the limiting reactant and from this amount, 824.21 grams of sodium chloride can be produced from the reaction 2 Na + Cl2.

Explanation:

To determine how many grams of sodium chloride (NaCl) can be produced from 500 grams of sodium (Na) and 500 grams of chlorine (Cl2), we need to use stoichiometry and the balanced chemical equation:

2 Na (s) + Cl2 (g) → 2 NaCl (s)

First, we should convert the mass of the reactants to moles using their molar masses (Na = 22.99 g/mol, Cl2 = 70.90 g/mol). Then, we compare the mole ratio from the balanced equation to identify the limiting reactant. The limiting reactant will determine the maximum amount of product that can be formed.

For sodium: 500 g Na × (1 mol Na / 22.99 g Na) = ~21.75 mol Na

For chlorine: 500 g Cl2 × (1 mol Cl2 / 70.90 g Cl2) = ~7.05 mol Cl2

From the balanced equation, we know that 1 mole of Cl2 reacts with 2 moles of Na. Here, Cl2 is the limiting reactant, and it will determine the number of moles of NaCl that can be formed:

7.05 mol Cl2 × (2 mol NaCl / 1 mol Cl2) = 14.1 mol NaCl

To find the mass of NaCl produced, we multiply the moles of NaCl by its molar mass (NaCl = 58.44 g/mol):

14.1 mol NaCl × (58.44 g NaCl / 1 mol NaCl) = ~824.21 g NaCl

Therefore, 824.21 grams of NaCl can be formed from 500 grams each of Na and Cl2 when using the correct stoichiometry of the reaction.

gluons because they so tightly  glue quarks together.

The radius of an electron in the third shell of the hydrogen atom, according to the Bohr model, is calculated as 4.7628 x 10⁻¹⁰ meters.

To calculate the radius of an electron in the third shell (n=3) of the hydrogen atom according to the Bohr model of the hydrogen atom, you use the formula that relates the main quantum number (n) to the radius of the electron's orbit. The radius of an orbit (rn) in the Bohr model is given by the equation rn = n2 imes ao, where ao is the Bohr radius and equals 5.292  imes 10
11 m. For the third shell, n=3, so the calculation is r3 = 32  imes 5.292 imes 10-11 m = 9 imes 5.292 imes 10-11 m.

Therefore, the radius of an electron in the third shell is r3 = 47.628 imes 10-11 m = 4.7628 imes 10-10 m. Keep in mind that while this model provides insight, it has been refined by quantum mechanics.

OPTION A.

In nuclear decay, if the atomic number decreases by one but the mass number is unchanged, the radiation emitted is a positron. This type of decay is known as positron emission.

During nuclear decay, if the atomic number decreases by one but the mass number is unchanged, the radiation emitted is, in fact, a positron. This type of decay is called positron emission. In positron emission, a proton in the nucleus is converted into a neutron, and a positron is emitted. This process leads to a decrease in the atomic number by one unit but the mass number remains unchanged as the overall amount of nucleons (protons + neutrons) is conserved.

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During nuclear decay, if the atomic number decreases by one but the mass number is unchanged, the radiation emitted is a beta particle.

During nuclear decay, if the atomic number decreases by one but the mass number is unchanged, the radiation emitted is a beta particle. Beta particles are high-energy electrons or positrons that are emitted during the decay of a nucleus. They have a negative charge and are smaller than alpha particles, making them capable of penetrating further through materials. This type of decay is referred to as beta decay.

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It will be appropriate for bill to stay for 30 minutes.

Answer:

1.0 x 10⁻⁹ M.

Explanation:

∵ pH = - log[H⁺].

∴ 5.0 = - log[H⁺].

log[H⁺] = - 5.0.

∴ [H⁺] = 1.0 x 10⁻⁵ M.

∵ [H⁺][OH⁻] = 10⁻¹⁴.

∴ [OH⁻] =  10⁻¹⁴/[H⁺] = (10⁻¹⁴)/(1.0 x 10⁻⁵ M) = 1.0 x 10⁻⁹ M.

Answer:

3.it increases

Explanation:

Final answer:

The force of attraction decreases when the distance between two objects increases, according to the inverse-square law for forces like gravity and electrostatic forces.

Explanation:

When the distance between two objects increases, the force of attraction between them decreases. This principle is observed in both gravitational and electrostatic forces. The magnitude of the force actually decreases as the square of the distance increases. If the distance doubles, the force between the objects would decrease to one fourth of its original value. Additionally, an increase in mass for an object in uniform circular motion will result in an increase of the required centripetal force to maintain the same speed.

Answer:

Sublimation occurs in solids with vapor pressures that exceed atmospheric pressure at or near room temperature.

Explanation:

For a solid to undergo sublimation, it must have relatively low intermolecular forces on the surface allowing it to transition directly from solid to gas with the addition of energy. The heat of sublimation (AHsub) is key in understanding this process, which involves the sum of the heat of fusion and vaporization.

A solid must have certain properties to undergo sublimation. Sublimation is the direct conversion of a solid to a gas without passing through the liquid phase. To sublimate, the solid should have sufficient intermolecular forces on the surface that can be overcome relatively easily with the addition of energy, such as heat. This is why substances with higher vapor pressures near room temperature can often undergo sublimation.

The amount of energy required for a solid to sublimate is indicated by the heat of sublimation (AHsub), which is the sum of the heat of fusion (AHfus) and the heat of vaporization (AHvap). This is an application of Hess's law and signifies the total amount of energy needed to change the phase from solid to gas. The equation Q = mLs is used to calculate the energy involved in the process, where Ls represents the heat of sublimation.

Common examples of substances that can sublimate include dry ice (CO2), iodine, naphthalene, and 1,4-dichlorobenzene. Substances that sublimate have unique uses, such as dry ice being a good refrigerant, because it cools through the endothermic sublimation process without leaving a liquid residue as it transitions to gas.

Answer:

160.9 mol ≅ 161.0 mol.

Explanation:

Using cross multiplication:

1.0 mole of Fe(NO₃)₃ contains → 6.022 x 10²³ formula units.

??? mole of Fe(NO₃)₃ contains → 9.69 x 10²⁵ formula units.

∴ The no. of moles of He contains (9.69 x 10²⁵ formula units) = (1.0 mol)(9.69 x 10²⁵ formula units.)/(6.022 x 10²³ formula units) = 160.9 mol ≅ 161.0 mol.

Answer:

Iron

Explanation:

Heat released by the metal sample will be equivalent to the heat absorbed by  water.

But heat = mass × specific heat capacity × temperature change

Thus;

Heat released by the metal;

= 45.9 g × c ×(95.2 -24.5) , where c is the specific heat capacity of the metal

= 3245.13c joules

Heat absorbed by water;

= 120 g × 4.18 J/g°C × (24.5-21.6)

= 1454.64 joules

Therefore;

3245.13c joules = 1454.64 joules

c = 1454.64/3245.13

  = 0.448 J/g°C

The specific heat capacity of the  metal sample is 0.448 J/g°C. The metal use is most likely, Iron.

The metal used is copper.

The specific heat equation, q = mcΔT, can be used to determine the metal used. By plugging in the given values and solving for the metal's specific heat, we find that the closest value is to copper. Therefore, the metal used is copper.

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Answer:

18.94%.

Explanation:

kt = ln [A₀]/[A]

k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.

t is the time = 13,750 years.

[A₀] is the initial percentage of carbon-14 = 100.0 %.

[A] is the remaining percentage of carbon-14 = ??? %.

∵ kt = ln [Ao]/[A]

∴ (1.21 x 10⁻⁴ year⁻¹)(13,750 years) = ln (100.0%)/[A]

1.664 =  ln (100.0%)/[A]

Taking exponential for both sides:

5.279 = (100.0%)/[A]

∴ [A] = (100.0%)/5.279 = 18.94%.

If a tree dies and the trunk remains undisturbed for 13,750 years, 18.94% of the original C-14 will still be present.

Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation.

C-14 decays with a half-life (th) of 5730 years. We can calculate the rate constant (k) using the following expression.

k = ln2 / th = ln2 / 5730 y = 1.210 × 10⁻⁴ y⁻¹

The decay follows first-order kinetics. We can calculate the fraction of the original C-14 after 13,759 years using the following expression.

[tex][C]/[C]_0 = e^{-k.t} \\[C]/[C]_0 = e^{-(1.210.10^{-4}y^{-1} ).(13,750y)} = 0.1894 = 18.94 \%[/tex]

where,

If a tree dies and the trunk remains undisturbed for 13,750 years, 18.94% of the original C-14 will still be present.

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Answer:

Oxygen is a product of photosynthesis and a reactant in cellular respiration.

Explanation:

During photosynthesis green plants manufacture their food using carbon dioxide and water in the presence of sunlight. The product of this reaction is formation of food and oxygen gas to the environment. Therefore, oxygen is given off during photosynthesis.

During cellular respiration, organisms use oxggen gas to liberate energy from food. Most times carbon dioxide is the waste product from the reaction.

Final answer:

Oxygen is produced as a byproduct of photosynthesis and consumed as a reactant in cellular respiration. These two processes are connected in the carbon cycle, recycling oxygen and carbon dioxide in Earth's atmosphere.

Explanation:

The role of oxygen in photosynthesis and cellular respiration is reciprocal. During photosynthesis, oxygen is produced as a byproduct when water molecules are split to provide electrons. This process consumes carbon dioxide and releases oxygen. On the other hand, during cellular respiration, oxygen is a reactant that works alongside glucose to produce ATP, which is the main energy currency in cells. As a result, carbon dioxide and water are generated as waste products.

Photosynthesis and cellular respiration are intimately connected in the biological carbon cycle. The oxygen released during photosynthesis is the same oxygen that is consumed during cellular respiration. This relationship sustains life on Earth by recycling oxygen and carbon dioxide in the atmosphere. Oxygen also enables cellular respiration to occur efficiently, allowing organisms to produce the ATP necessary for cellular functions.

Answer:

12.81.

Explanation:

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

M = (mass/molar mass) NaCl / (Volume of the solution (L))

mass of Ba(OH)₂ = 274 mg = 0.274 g, molar mass of Ba(OH)₂ = 171.34 g/mol, Volume of water = 50.0 mL = 0.05 L.

M = (mass/molar mass) Ba(OH)₂ / (Volume of the solution (L)) = (0.274 g / 171.34 g/mol) / (0.05 L) = 0.03 M.

Ba(OH)₂ → Ba²⁺ + 2OH⁻,

Every 1.0 mol of Ba(OH)₂ gives 2.0 moles of OH⁻.

∴ [OH⁻] = 2(0.032 M) = 0.064 M.

∵ pOH = -log[OH⁻]

∴ pOH = -log(0.064) = 1.194.

∵ pH + pOH = 14.

∴ pH = 14 - pOH = 14 - 1.194 = 12.81.

Answer:  (a) [tex]Pb^{2+}[/tex]

Explanation:

The metal with negative reduction potential will easily lose electrons and thus is oxidized and the one with positive reduction potential will easily gain electrons and thus is reduced.

Where both [tex]E^0[/tex] are standard reduction potentials.

[tex]E^0_{[Pb^{2+}/Pb]}=-0.126V[/tex]

[tex]E^0_{[Cr^{3+}/Cr]}=-0.74V[/tex]

[tex]E^0_{[Fe^{2+}/Fe]}=-0.44V[/tex]

[tex]E^0_{[Sn^{2+}/Sn]}=-0.13V[/tex]

Thus here [tex]Pb^{2+}[/tex] with negative reduction potential and least magnitude has the most tendency to gain electrons and thus can be most easily reduced.

The study of chemicals and bonds is called chemistry. There are different types of elements and these are metals and nonmetals.

The wavelength is the spatial period of a periodic wave.

According to the question, the answer to both questions is as follows:-

For more information about the matter, refer to the link:-

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Answer:

Explanation:

Balance is achieved when a reaction is in equilibrium.

At equilibrium, the rate of forward reaction is equal to the rate of backward or reverse process.