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Answer:

Explanation:

probably C

66.5 mL of 0.300 M NaF is required to make a 0.0795 M solution of NaF if diluted to 250.0 mL with water.

In order to determine the number of ml of 0.300 M NaF needed to make a 0.0795 M solution of NaF when diluted to 250.0 ml with water, we can use the following formula:

\(M_1V_1 = M_2V_2\),

where \(M_1\) is the initial molarity,

\(V_1\) is the initial volume,

\(M_2\) is the final molarity, and \(V_2\) is the final volume.

So:

\(V_1 = V_2(M_2/M_1)V_1\)

= (250.0 mL)(0.0795 M/0.300 M)\(V_1\)

= 66.5 mL

Therefore, 66.5 mL of 0.300 M NaF would be required to make a 0.0795 M solution of NaF when diluted to 250.0 mL with water.

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Answer:

Below

Explanation:

When the flame in a hot air balloon is turned down, the amount of heat being generated inside the balloon decreases. This causes the temperature inside the balloon to decrease as well. As the temperature inside the balloon decreases, the air inside the balloon cools and contracts. This causes the air inside the balloon to become less dense than the air outside the balloon, resulting in a decrease in the overall lifting force of the balloon. As a result, the balloon will start to descend gradually.

Additionally, turning down the flame will also reduce the volume of hot air being released into the balloon, which can cause the balloon to lose altitude more quickly.

It's important to note that the pilot must adjust the flame in a hot air balloon to maintain the altitude and direction of the balloon. As the air outside cools, the pilot needs to turn up the flame to maintain the temperature inside the balloon and to keep the balloon afloat

When the flame in a hot air balloon is turned down, the amount of heat being generated inside the balloon decreases. This causes the temperature inside the balloon.

to decrease as well. As the temperature inside the balloon decreases, the air inside the balloon cools and contracts. This causes the air inside the balloon to become less dense than the air outside the balloon, resulting in a decrease in the overall lifting force of the balloon. As a result, the balloon will start to descend gradually. Additionally, turning down the flame will also reduce the volume of hot air being released into the balloon, which can cause the balloon to lose altitude more quickly. It's important to note that the pilot must adjust the flame in a hot air balloon to maintain the altitude and direction of the balloon. As the air outside cools, the pilot needs to turn up the flame to maintain the temperature inside the balloon and to keep the balloon afloat.

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Answer:

They are both nuclear reactions that produce energy.

The height of the sheet pile above the ground surface will be 6 + 5.125 = 11.125 m.Therefore, the correct answer is C, 4.872 m.

The right answer is option C, 4.872 m.Explanation:Given,Depth of weir (h)

= 6 m Soil strata depth

= 16 mBase length of weir (B)

= 20 m Foundation depth (df)

= 2 mHead of water retained (H)

= 8 m Permeability coefficient (k)

= 4.6 × 10⁻⁴ m/s Specific gravity (G)

= 2.65Void ratio (e)

= 0.72

To calculate: The height of sheet pile above the weir crest, h1 Assuming the flow is in the horizontal direction from left to right, the weir will act as a vertical wall. Let h1 be the height of the sheet pile above the weir crest.As the water level will be retained to a height of 8 m, the total head on the soil below the sheet pile will be H + h1. Applying the Darcy's law, we can obtain the seepage velocity as:v

= ki.e., v

= 4.6 × 10⁻⁴ × (8 + h1)

So,The seepage velocity at the weir base will be:v

= 4.6 × 10⁻⁴ × (8 + h1)

= (kh/B) × i.e., 4.6 × 10⁻⁴ × (8 + h1)

= (4.6 × 10⁻⁴ × 16) / 20

Hence,

8 + h1

= 2.875

Solving this equation, we get,h1

= 2.875 − 8

= −5.125 m.

Thus, the height of the sheet pile above the weir crest is -5.125 m which means that the sheet pile will extend 5.125 m below the ground surface. The height of the sheet pile above the ground surface will be

6 + 5.125

= 11.125 m.

Therefore, the correct answer is C, 4.872 m.

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A redox reaction's hydroxide ion component involving oxidation or reduction is referred to as a half reaction. By taking into account, we get a half reaction.

The diatomic anion OH, which is made up of oxygen and hydrogen atoms, is most frequently referred to in chemistry as hydroxide. It is among the known simplest diatomic ions. The group of substances that contain the hydroxide ion is referred to as "hydroxide" as well.

Galvanic cell with Zn and Cu as an example. CuSO4(aq) Zn(s) + CuSO4(aq) (s) Oxidation occurs at the Zn anode (the metal loses electrons). This can be seen in the oxidation half-reaction shown below (see how the electrons are on the products side): Zn(s) equals Zn2+ + 2e.

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Answer:

The value \(N_A = 0.192 \ mol \cdot m^{-2} \cdot \ s\)

Explanation:

From the question we are told that

     The thickness of the air is \(z_2 - z_1 = 1 \ cm =0.01 \ m\)

      The temperature is  \(T = 25^oc = 25 +273 = 298 \ K\)

     The total pressure is  \(P_T = 1 atm = 1.01325*10^{5} \ Pa\)

      The partial pressure of Ammonia first side is  \(P_{AO} = 0.9 \ atm = 0.9 * 1.01325*10^{5} = 91192.5 \ Pa\)

      The partial pressure of Ammonia to the second side is \(P_{A} = 0.1 \ atm = 0.1 * 1.0325*10^{5} = 10132.5 \ Pa\)

 Rate of flow of ammonia is  

          \(D_{AB} = 0.214 \ cm/s = \frac{0.214 }{10000} = 2.14 *10^{-5} \ m^2 /s\)

Generally the  molar flux of ammonia is mathematically represented as

         \(N_A = \frac{D_{AB} * P_T }{RT(z_2 -z_1)} * ln [\frac{P_T - P_{Al}}{P_T - P_{AO}} ]\)

Here R is the gas constant with value  

         \(R = 8.314 \ m^3 \cdot Pa \cdot mol^{-1} \cdot K\)

             \(N_A = \frac{2.14 *10^{-5} * 1.01325*10^{5} }{8.314 *298 (0.01)} * ln [\frac{1 - 0.1}{1 - 0.9} ]\)

=>           \(N_A = 0.192 \ mol \cdot m^{-2} \cdot \ s\)

Answer:

F = 50 N

Explanation:

Given data:

Mass of car = 250 Kg

Acceleration of car = 0.20 m/s²

Force required = ?

Solution:

Formula:

F = m×a

F = applied  force

m = mass

a = acceleration

Now we will put the values in formula.

F =  250 Kg × 0.20 m/s²

F = 50 Kg.m/s²

Kg.m/s² = N

F = 50 N

Answer:

the average distance of the outermost electron shell from. the nucleus.

Explanation:

3 moles of oxygen gives 2 moles of the product. Then, 2.50 g or 0.07 moles of oxygen gas will give, 0.04 moles or 14.8 g of Fe₂O₃.

Metals are easily reactive towards atmospheric oxygen and they form their oxides. Fe reacts with oxygen to form one of its oxide in the  + 3 oxidation state that is Fe₂O₃.

Here, 3 moles of oxygen gives 2 moles of the oxide.

molar mass of oxygen gas = 32 g/mol

no.of moles in 2.5 g = 2.5 /32 = 0.07 moles.

0.07 moles produce, 0.07 × 2 /3 = 0.04 moles.

molar mass of Fe₂O₃ = 319.2 g.

then, mass of 0.04 moles = 0.04 × 319.2 = 14.8 g.

Therefore, 2.5 g of oxygen gas will give 14.8 g of the product.

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When 3-methylcyclohexene undergoes allylic halogenation with one equivalent of NBS (N-bromosuccinimide), peroxide, and light, it can form two allylic halides.

The reaction involves the addition of a bromine atom to the allylic position of the alkene. The two possible products are formed by the addition of the bromine atom to the two different allylic carbons in the 3-methylcyclohexene molecule.

The two allylic halides that can be formed are:

1-Bromo-3-methylcyclohexene (with the bromine atom attached to the allylic carbon adjacent to the methyl group).

1-Bromo-1-methylcyclohexene (with the bromine atom attached to the allylic carbon adjacent to the non-methyl substituted carbon).

These two compounds are stereoisomers of each other since they have the same connectivity but differ in the spatial arrangement around the double bond.

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Answer:

5 moles

Explanation:

By convert grams to moles u need to divided the number of grams to the molar mass

220 ÷ 44.01 = 4.9 ≈ 5.0

The concentration of the original Ba(OH)₂ solution if 15.0 ml solution of Ba(OH)₂ is neutralized with 22.7 ml of 0.200 m HCl is 151.3 mol/dm³

To determine concentration of the original Ba(OH)₂ solution, we must know he balanced chemical equation for the neutralization reaction is:

Ba(OH)₂ + 2HCl → BaCl₂ + 2H₂O

From the equation above, the stoichiometric ratio of Ba(OH)₂ and HCl is 1:2. That means one mole of Ba(OH)₂ reacts with 2 moles of HCl. The balanced chemical equation also shows that the number of moles of HCl used is the same as the number of moles of Ba(OH)₂. Hence:

moles of HCl = 0.200 mol/dm³ × 22.7 dm³ = 4.54 mol

Using the stoichiometric ratio, the moles of Ba(OH)₂ in the solution can be calculated to be:

moles of Ba(OH)₂ = 4.54 mol ÷ 2 = 2.27 mol

The volume of the Ba(OH)₂ solution is 15.0 mL, which is 0.015 dm³. Therefore, the concentration of the original Ba(OH)₂ solution can be calculated as:

concentration = moles/volume= 2.27 mol ÷ 0.015 dm³= 151.3 mol/dm³

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The concentration of the original Ba(OH)₂ solution is 0.302 M.

Given data

Volume of Ba(OH)₂ solution used = 15.0 ml

Volume of HCl used = 22.7 ml

Molarity of HCl solution used = 0.200 M

We need to calculate the concentration of Ba(OH)₂ solution, which is not known.Molar ratio of HCl and Ba(OH)₂ in a balanced chemical equation of their neutralization is;

HCl + Ba(OH)₂ → BaCl₂ + 2H₂O

The balanced chemical equation tells us that 1 mole of HCl is required to neutralize 1 mole of Ba(OH)₂.

So, the moles of HCl used in the reaction is;

moles of HCl = molarity × volume (in liters)

moles of HCl = 0.200 M × 0.0227 L = 0.00454 mole

Since one mole of HCl reacts with 1 mole of Ba(OH)₂,

so the number of moles of Ba(OH)₂ used is also equal to 0.00454 mole. Since we know the volume of the Ba(OH)₂ solution used, we can calculate the molarity of the solution as;

molarity = moles of solute / volume of solution in liters

Molarity = 0.00454 / (15.0 / 1000) = 0.302 M

Therefore, the concentration of the original Ba(OH)₂ solution is 0.302 M.

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Explanation:

1.4grams/mL

density is a ratio of mass to volume

Explanation:

When a substance is heated, it gains thermal energy. Therefore, its particles move faster and its temperature rises. When a substance is cooled, it loses thermal energy, which causes its particles to move more slowly and its temperature to drop.

When the temperature of a substance is increased, i.e., if you double the Kelvin temperature of a substance, you double the average kinetic energy of its molecules. When the average kinetic energy of the molecules goes up (a rise in temperature), the average speed of the molecules increases.

Answer:

heating the sugar

Explanation:

Answer:

softening butter...

Explanation:

that sounds the best because the butter be melting

In Trials 1 and 2, respectively, 0.409 g and 0.406 g of magnesium metal were employed. In Trial 1 and Trial 2, the theoretical yield of MgO was 0.680 g and 0.675 g, respectively. In Trial 1 and Trial 2, the actual yield of MgO was 0.672 g and 0.665 g, respectively.

Metals are substances that develop naturally beneath the Earth's surface. Most metals are shiny or glossy. Because they are inorganic, metals are composed of materials that have never been living.

To calculate the mass of magnesium metal used in each trial, we need to subtract the mass of the empty crucible with lid from the mass of the crucible, lid, and magnesium metal.

For Trial 1:

Mass of Mg metal = (Mass of Mg, crucible, and lid) - (Mass of empty crucible with lid)

Mass of Mg metal = 27.093 g - 26.684 g = 0.409 g

For Trial 2:

Mass of Mg metal = (Mass of Mg, crucible, and lid) - (Mass of empty crucible with lid)

Mass of Mg metal = 27.098 g - 26.692 g = 0.406 g

To calculate the theoretical yield of magnesium oxide, we need to use the balanced chemical equation for the reaction. Assuming that all the magnesium reacted with oxygen to form magnesium oxide, the theoretical yield can be calculated as follows:

Mg + 1/2 O₂ → MgO

Molar mass of Mg = 24.31 g/mol

Molar mass of MgO = 40.31 g/mol

For Trial 1:

Theoretical yield of MgO = (Mass of Mg metal used / Molar mass of Mg) x (Molar mass of MgO)

Theoretical yield of MgO = (0.409 g / 24.31 g/mol) x (40.31 g/mol) = 0.680 g

For Trial 2:

Theoretical yield of MgO = (Mass of Mg metal used / Molar mass of Mg) x (Molar mass of MgO)

Theoretical yield of MgO = (0.406 g / 24.31 g/mol) x (40.31 g/mol) = 0.675 g

The actual yield is the mass of the product (MgO) obtained experimentally.

For Trial 1:

Actual yield of MgO = Mass of MgO, crucible, and lid - Mass of empty crucible with lid

Actual yield of MgO = 27.356 g - 26.684 g = 0.672 g

For Trial 2:

Actual yield of MgO = Mass of MgO, crucible, and lid - Mass of empty crucible with lid

Actual yield of MgO = 27.357 g - 26.692 g = 0.665 g

The percent yield can be calculated using the following formula:

Percent yield = (Actual yield / Theoretical yield) x 100%

For Trial 1:

Percent yield of MgO = (0.672 g / 0.680 g) x 100% = 98.82%

For Trial 2:

Percent yield of MgO = (0.665 g / 0.675 g) x 100% = 98.52%

To calculate the average percent yield of MgO, we add the percent yields of both trials and divide by 2.

Average percent yield of MgO = (Percent yield of Trial 1 + Percent yield of Trial 2) / 2

Average percent yield of MgO = (98.82% + 98.52%) / 2 = 98.67%

Therefore, the mass of magnesium metal used in Trial 1 was 0.409 g, and in Trial 2 was 0.406 g. The theoretical yield of MgO was 0.680 g in Trial 1 and 0.675 g in Trial 2. The actual yield of MgO was 0.672 g in Trial 1 and 0.665 g in Trial 2.

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Carbohydrate atoms usually have how hydrogen atoms as compared to oxygen atoms

Answer:

10.801=11

Explanation:

avarage atomic mass =relative abundance of first isotope*mass number of first isotope/100+relative abundance of second isotope*mass number of second isotope/100

The element present in the column of lithium may be Hydrogen, sodium, potassium, rubidium, cesium and francium.

Hydrogen (H), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr) are the elements which can be found in the column of lithium. Lithium belongs to the first group in periodic table which is also called alkali metals.

All the elements in the first group contain only one electron in its outermost shell so they are very reactive and make bonds with other elements in the periodic table making different types of chemicals so we can conclude that the element present in the column of lithium may be Hydrogen (H), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).

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Answer:

.668 mole

Explanation:

1.67 * .4 = .668 mole

Answer: EXAMPLEEE

Explanation: Brookite

Mohs scale hardness 51⁄2 to 6

Luster Submetallic

Streak White, greyish or yellowish

Diaphaneity Opaque to translucent

The correct answer is CO2. CO2 is a linear molecule with two identical oxygen atoms bonded to a central carbon atom.

The electronegativity difference between the carbon and oxygen atoms is zero, meaning that the bond dipoles cancel each other out, resulting in a nonpolar molecule. Since dipole-dipole interactions occur between polar molecules, CO2 will not participate in dipole-dipole interactions.

On the other hand, SO2, H2O, and H2S are polar molecules with a net dipole moment, which allows them to participate in dipole-dipole interactions.

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The concentration of copper (II) sulfate when it's absorbance is 2.17 is 0.22 M.

The concentration of copper (II) sulfate when it has absorbance value 2.17 is found out by  cross multiplying  concentration of 0.10 M solution with it's absorbance and then dividing it by absorbance of 0.10 M copper sulfate solution.That is,

0.10×2.17/0.96=0.22 M

The law suggests a linear relationship between absorbance and concentration of a solution.The law states that, absorbance of a solution is directly proportional to the concentration and the path length that is,

A=C×l

where l=path length

Thus, it can be inferred from the law that as absorbance of solution increases it's concentration also increases as they are directly proportional.

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The amount of energy required to evaporate a given number of moles of pentene is given by the formula:

ΔHvap = energy/mole Rearranging the formula gives:

Mol = Energy/ΔHvap Substituting the given values, we get:

mol = (88 J) / (29.82 kJ/mol) = 0.0029488 mol Rounding to the correct number of significant digits gives:

Moles = 0.003 Moles

Thus, 0.003 moles of pentene can be evaporated while supplying 88 J of energy.

What is evaporation?

When a liquid becomes a gas, this process is called evaporation. If you boil water in a pot, you can observe the evaporation. Evaporation is done in two ways:evaporation and boiling.  

What is the difference between vaporize and vaporize?

Evaporation is defined as a phase transition of a compound or element that occurs during the boiling or sublimation process. Evaporation is just a type of evaporation that normally occurs at temperatures below the boiling point.  

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Answer:

.9375 x 10⁻³ moles .

Explanation:

2.5 mEq / L of Magnesium ion

2.5 x 10⁻³ Eq / L

= 2.5 x 10⁻³ / 2 mole / L    [  1 mole = 2 Eq ]

= 1.25 x 10⁻³ mole / L

1 L contains 1.25 x 10⁻³ mole

750 mL = .75 x 1.25 x 10⁻³ mole

= .9375 x 10⁻³ mole .

So 750 mL contains .9375 x 10⁻³ moles .