A pH of 5 is considered to be neutral

Answer:its b

Explanation:

jusut bcss

The minimum concentration of fluoride ions needed is 2.726 x 10⁻⁴ M.

To find the minimum concentration of fluoride ions needed to precipitate CaF₂, we'll use the solubility product constant (Ksp) and the calcium ion concentration.

Ksp = [Ca²⁺][F⁻]²

Given: [Ca²⁺] = 5.25 x 10⁻³ M, Ksp = 3.9 x 10⁻¹¹

3.9 x 10⁻¹¹ = (5.25 x 10⁻³)[F⁻]²

Solve for [F⁻]:

[F⁻]² = (3.9 x 10⁻¹¹) / (5.25 x 10⁻³)

[F⁻]² = 7.4286 x 10⁻⁹

[F⁻] = 2.726 x 10⁻⁴ M

The minimum concentration of fluoride ions needed is 2.726 x 10⁻⁴ M.

Read more about concentration here:

https://brainly.com/question/17206790

#SPJ1

The sample of the unknown metal has the mass of the 135 grams. The sample cools from the 100.5 °C to the 35.5 °C, and it releases the 7500 joules of the energy. The specific heat of the sample is 0.854 J/g °C.

Th mass of the metal = 135 g

The initial temperature = 100.5 °C

The final temperature = 35.5 °C

The heat energy releases = - 7500 J

The heat energy is expressed as :

Q = mc ΔT

Where,

The m is mass of the metal = 135 g

The c is the specific heat capacity = ?

The Q is heat energy releases = - 7500 J

The ΔT is the change in the temperature = final temperature - initial temperature.

The ΔT is the change in the temperature = 35.5 - 100.5

The ΔT is the change in the temperature =  - 65 °C

The specific heat capacity, c = Q / m ΔT

The specific heat capacity, c = - 7500 / 135 × - 65

The specific heat capacity, c = 0.854 J/g °C

The specific heat capacity of metal is 0.854 J/g °C.

To learn more about specific heat here

https://brainly.com/question/19907993

#SPJ1

Answer:

Since that means that we have 0.223 moles of PbCl2 in 1000mL of solution.

Also since mole ratio of the ions Pb2+:Cl- is 1:2

Thus, moles of Pb2+ = 0.223moles

concentration of Pb2+= 0.223M

Moles of Cl- = 2x0.223 moles

Concentration of Cl- = 0.446M

Explanation:

The pressure of hydrogen gas formed is 709.5 mmHg.

Partial pressure is the pressure exerted by a single gas component in a mixture of gases, assuming all other gases are held constant.

In this case, the hydrogen gas is formed by a chemical reaction.

To calculate the partial pressure of hydrogen gas, we need to subtract the vapor pressure of water from the total pressure of the gas collected.

The vapor pressure of water at 18.0 °C is 15.5 mmHg.

Therefore, the partial pressure of hydrogen gas can be calculated as:

Partial pressure of hydrogen gas = Total pressure - Vapor pressure of water

Partial pressure of hydrogen gas = 725.0 mmHg - 15.5 mmHg = 709.5 mmHg

To know more about hydrogen gas here

brainly.com/question/12494649

#SPJ1

Answer:

OB. formation of new elements.

Nuclear reactions involve changes in the nucleus of an atom, such as the splitting of a nucleus or the combining of two nuclei. These reactions can result in the formation of new elements, as the number of protons in the nucleus determines the element. In contrast, chemical reactions involve the rearrangement of electrons between atoms to form new compounds, but do not involve changes to the nucleus.

C₂H₄O₂ + NaHCO₃ —> NaC₂H₃O₂ + H₂O + CO₂ the amount of Carbon dioxide produced is 5.28 mg.

Water, CO₂ , and C₂H₃NaO₂ were produced when acetic acid and NaHCO₃ were combined. The chemistry is as follows: The reaction between vinegar and baking soda was endothermic.

Acetic acid:  2(12.01 g/mol) + 4(1.01 g/mol) + 2(16.00 g/mol)

                                              = 60.05 g/mol

NaHCO₃ 22.99 g/mol + 1.01 g/mol + 3(16.00 g/mol)

                                             = 84.01 g/mol

100 mg of Acetic acid is equal to 0.1 g, and 10 mg of NaHCO₃ is equal to 0.01 g.

Number of moles of Acetic acid = 0.1 g / 60.05 g/mol

                                             = 0.00167 mol

Number of moles of NaHCO₃  = 0.01 g / 84.01 g/mol

                                               = 0.00012 mol

Since NaHCO₃ has fewer moles, it is the limiting reactant.

Therefore, 0.00012 mol of NaHCO₃  will produce 0.00012 mol of CO₂

The mass of CO₂ produced can be calculated as follows:

Mass of CO₂ = Number of moles of CO₂  x Molar mass of CO₂

Mass of CO₂ = 0.00012 mol x 44.01 g/mol

                             = 0.00528 g or 5.28 mg

Therefore, the amount of CO₂ produced is 5.28 mg.

The theoretical yield of CO₂ is 0.00012 mol x 44.01 g/mol

                               = 0.00528 g or 5.28 mg.

This is equal to the actual yield of CO₂ produced.

To know more about Bicarbonate :

brainly.com/question/8560563

#SPJ1

Answer:

1.02 J/g°C.

Explanation:

We can use the equation:

q = m * c * ΔT

where q is the heat absorbed or released, m is the mass of the substance (in grams), c is the specific heat, and ΔT is the change in temperature (in Celsius).

First, we can calculate the heat gained by the water:

q_water = m_water * c_water * ΔT_water

where m_water is the mass of the water (in grams), c_water is the specific heat of water (4.184 J/g°C), and ΔT_water is the change in temperature of the water.

m_water = 120 g

c_water = 4.184 J/g°C

ΔT_water = (32°C - 24°C) = 8°C

q_water = (120 g) * (4.184 J/g°C) * (8°C) = 4009 J

This means that the heat lost by the unknown solid is equal to the heat gained by the water:

q_solid = -q_water

q_solid = -4009 J

Next, we can calculate the change in temperature of the solid:

ΔT_solid = (32°C - 80°C) = -48°C

Now, we can solve for the specific heat of the solid:

q_solid = m_solid * c_solid * ΔT_solid

-4009 J = (90.0 g) * c_solid * (-48°C)

c_solid = -4009 J / (90.0 g * -48°C)

c_solid = 1.02 J/g°C

Therefore, the specific heat of the unknown solid is 1.02 J/g°C.

The solubility of NH₃ in water at 90°C is approximately 0.03 g per 100 g of water.

The solubility can be determined from a solubility table or by using the appropriate equilibrium constant.

According to a solubility table, the solubility of ammonia in water at 90°C is approximately 88 g per 100 g of water.

Alternatively, the equilibrium constant for the dissolution of ammonia in water at 90°C can be used to calculate the solubility.

The equilibrium constant (K) for the reaction:

NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH- (aq)

is approximately 1.76 x 10⁻⁵ at 90°C.

Using the equilibrium constant expression:

K = [NH4+][OH-]/[NH3][H2O]

Assuming that the concentration of water remains constant at 100 g per 100 g of solution, and that the concentration of NH4+ and OH- are negligible compared to that of NH3, the solubility of NH3 can be calculated as:

[NH3] = K[H2O] = 1.76 x 10⁻⁵ x 100 = 1.76 x 10⁻³ mol/L

Converting to grams per 100 g of water:

1.76 x 10⁻³ mol/L x 17.03 g/mol = 0.03 g/100 g of water

Learn more about solubility here: https://brainly.com/question/23946616

#SPJ1

The complete question is below:

determine the solubility of NH₃ in water at 90° C​

The mass of hydrogen produced in the reaction is 2g.

The mole is an amount unit similar to familiar units like pair, dozen, gross, etc. It provides a specific measure of the number of atoms or molecules in a bulk sample of matter.

A mole is defined as the amount of substance containing the same number of atoms, molecules, ions, etc. as the number of atoms in a sample of pure 12C weighing exactly 12 g.

Given,

Mass of Zn = 65g

Mass of HCl = 72g

Moles of Zn = mass / molar mass

= 65 / 65 = 1 mole

Moles of HCl = 72 / 36.5

= 1.97 moles

Since moles of Zn is lesser, therefore it is the limiting reagent.

From the reaction, 1 mole of Zn gives 1 mole of hydrogen

Moles of hydrogen = 1 mole

mass of hydrogen = moles × molar mass

= 1 × 2 = 2g

Therefore, the mass of hydrogen produced in the reaction is 2g.

Learn more about Moles, here:

https://brainly.com/question/31597231

#SPJ2

Interpreting Data:

Predicting:

Joshua's brother has a 50% chance of being a carrier for cystic fibrosis (Nn) and a 50% chance of having the normal genotype (NN). This is because Joshua's parents are both carriers, so each of their children has a 50% chance of inheriting the recessive allele.

Communicating:

As a genetic counselor, information about many generations of a family is needed to draw conclusions about a hereditary condition because traits are passed down from generation to generation. By studying the family history, we can identify patterns of inheritance and determine the likelihood that a person has inherited a certain trait. This information can help us make informed decisions about genetic testing and treatment options.

Additionally, knowing the family history can help us determine the risk of passing on a genetic condition to future generations.

Find out more on pedigree here: https://brainly.com/question/14525981

#SPJ1

Image transcribed and complete question:

Family Puzzle

Problem

A husband and wife want to understand the probability that their children might inherit cystic fibrosis. How can you use the information in the labeled Case Study to predict the probability?

Skills Focus

interpreting data, predicting

Materials

12 index cards

scissors marker

Procedure

1. Read the Case Study. In your notebook, draw a pedigree that shows all the family members. Use circles to represent the females, and squares to represent the males. Shade in the circles or squares representing the individuals who have cystic fibrosis.

2. You know that cystic fibrosis is controlled by a recessive allele. To help you figure out Joshua and Bella's family pattern, create a set of cards to represent the alleles. Cut each of six index cards into four smaller cards. On 12 of the small cards, write N to represent the dominant normal allele. On the other 12 small cards, write n for the recessive allele.

Case Study:

Joshua and Bella

• Joshua and Bella have a son named lan. lan has been diagnosed with cystic fibrosis.

⚫ Joshua and Bella are both healthy.

• Bella's parents are both healthy.

• Joshua's parents are both healthy. • Joshua's sister, Sara, has cystic fibrosis.

Analyze and Conclude

Write your answers in the spaces provided.

1. Interpreting Data What were the genotypes of Joshua's parents? What were the genotypes of Bella's parents?

2. Predicting Joshua also has a brother. What is the probability that he has cystic fibrosis? Explain.

3. Communicating Imagine that you are a genetic counselor. A couple asks why you need information about many generations of their families to draw conclusions about a hereditary condition. Write an explanation you can give to them.

More to Explore

Review the pedigree that you just studied. What data suggest that the traits are not sex-linked? Explain.

Answer:

When the gas is compressed, its molecules come closer and internal energy of gas is increased and the number of collisions will also increase. As the gas is compressed, the work done on it shows up as increased internal energy, which must be transferred to the surroundings to keep the temperature constant.

To answer these questions, we need to know what substance you are referring to, as well as the data from the experiment.

1. After a certain number of time intervals (shakes), one-half of your atoms (candies) would decay. This number would depend on the specific substance and its half-life.
2. The half-life of a substance is the time it takes for half of its atoms to decay.
3. If the half-life model decayed perfectly, the number of remaining atoms after 12 seconds would depend on the initial number of atoms and the half-life of the substance.
4. If you increased the initial number of atoms (candies) to 300, the overall shape of the graph would not be altered. This is because the half-life decay is a percentage-based process, meaning it would still follow an exponential decay pattern.
5. To calculate the percentage of decay for each three-second interval, you would divide the number of candies decayed by the number previously remaining and multiply by 100. This would show the percentage of decay for each interval.
6. This activity may not perfectly model the concept of half-life, but it can provide a close approximation. Any discrepancies may be due to experimental errors or limitations.
7. To compare how well this activity modeled the half-life of a radioactive element, you would need to analyze the decay percentages over time. If there are differences in the effectiveness of the half-life model, it could be due to the limitations of the experimental setup, such as using candies as a representation of atoms.

For more question on substance

https://brainly.com/question/24647756

#SPJ11

The correct ratio of components is:  For every 3 moles of carbon dioxide produced, 5 moles of oxygen react.

This ratio can be derived directly from the balanced chemical equation:

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

The balanced equation shows that for every 3 moles of carbon dioxide produced, 5 moles of oxygen are required. This means that if we have a certain amount of propane, we need to use this ratio to determine the amount of oxygen needed for the reaction. Similarly, if we have a certain amount of oxygen, we can use this ratio to calculate the amount of carbon dioxide that will be produced.

It is important to note that the other ratios provided in the question are incorrect because they do not match the coefficients in the balanced chemical equation.

Therefore, the correct option is: for every 3 moles of carbon dioxide produced, 5 moles of oxygen react.

To learn more about balanced equation here

https://brainly.com/question/31242898

#SPJ1

The total volume of the solution is 300 mL.

To calculate the total volume of the solution, we simply add the volumes of the ethanol and water together:

The total volume of solution = volume of ethanol + volume of water

= 100 mL + 200 mL

= 300 mL

Therefore, the total volume of the solution is 300 mL.

When two or more compounds are combined to form a solution, the substance present in the smallest amount is known as the solute, and the material present in the largest amount and which dissolves is known as the solvent.

The solute, which can be a solid, liquid, or gas, dissolves in the solvent, which is often a liquid.

In this scenario, 100 mL of ethanol and 200 mL of water are combined to make the solution. The solute in this solution is ethanol, a colorless liquid. Water is a polar solvent that can dissolve a wide range of compounds, including ethanol. When ethanol and water are combined, they dissolve and form a homogeneous mixture.

learn more about ethanol here

https://brainly.com/question/20814130

#SPJ1

(a) The formal charge of Cl in the hypochlorite ion (ClO-) is +1.

(b) The formal charge of Cl in the perchlorate ion (ClO4-) with single bonds is +3.

For chlorine (Cl):

Valence electrons: 7

Non-bonding electrons: 6 (3 lone pairs)

Bonding electrons: 2 (1 single bond with oxygen)

Formal charge of Cl = 7 - 6 - (1/2 * 2) = 7 - 6 - 1 = +1

Hence, the formal charge of Cl in the hypochlorite ion is +1.

(c) The oxidation number of Cl in the hypochlorite ion is +1.

(d) The oxidation number of Cl in the perchlorate ion with single bonds is +7.

(e) In a redox reaction, the hypochlorite ion (ClO-) would be more easily reduced because it has a lower oxidation number (+1) compared to the perchlorate ion (+7).

Read more about oxidation number here:

https://brainly.com/question/27239694

#SPJ1

C. It is absorbed and emitted in discrete chunks.

The energy in light is carried by particles called photons, which behave both like waves and like particles. According to the theory of quantum mechanics, photons can only be absorbed or emitted in discrete amounts of energy, known as quanta. This means that the energy in light is not continuous, but rather comes in specific packets or chunks. This phenomenon is known as quantization, and it has important implications for many areas of physics, including atomic and molecular physics, as well as the study of electromagnetic radiation.

Answer: C it is absorbed and emitted in descrete chunks.

Explanation:

photons of light are emitted or absorbed as electrons change energy levels

The hydrocarbon's molecular structure is [tex]C_9H_20[/tex].The hydrocarbon's empirical formula is [tex]C_9[/tex]/4H5.

To solve this problem, we need to use stoichiometry to relate the amount of [tex]CO__2[/tex] and [tex]H_2O[/tex] produced to the amount of [tex]CxHy[/tex] burned.

(a) To find the molecular formula of the hydrocarbon, we need to first calculate the number of moles of [tex]CO__2[/tex] and [tex]H_2O[/tex] produced. From the ideal gas law, we know that 1 mole of gas at STP (standard temperature and pressure) occupies 22.4 L. Therefore, 4.032 L of [tex]CO__2[/tex] at STP corresponds to:

4.032 L / 22.4 L/mol = 0.180 mol [tex]CO__2[/tex]

Similarly, the mass of H2O produced corresponds to:
3.602 g / 18.02 g/mol = 0.200 mol [tex]H_2O[/tex]

Since the hydrocarbon undergoes complete combustion, it reacts with oxygen to form [tex]CO__2[/tex] and [tex]H_2O[/tex] according to the balanced chemical equation:

[tex]CxHy[/tex] + (x + (y/4))O2 → [tex]CO__2[/tex] + (y/2)[tex]H_2O[/tex]
where x and y are the coefficients of the balanced equation. We can use the stoichiometric ratios to set up two equations:

0.180 mol [tex]CO__2[/tex] = x mol [tex]CxHy[/tex] → x = 0.180 mol / 0.0200 mol = 9
0.200 mol [tex]H_2O[/tex] = (y/2) mol [tex]CxHy[/tex] → y = 0.400 mol / 0.0200 mol = 20

Therefore, the molecular formula of the hydrocarbon is [tex]C_9H_20[/tex].
(b) To find the empirical formula of the hydrocarbon, we need to divide the subscripts by their greatest common factor. In this case, both subscripts are divisible by 4, so we get:

[tex]C_9H_20[/tex] → C9/4H5
Therefore, the empirical formula of the hydrocarbon is C9/4H5.

For more question on molecular

https://brainly.com/question/24191825

#SPJ11

The mass of the silver block, given that it was initially at 55.1 °C  and is submerged into 100.0 g of water at 25.0°C is 189.8 g

We'll begin our calculation by obtaining the heat absorbed by the water. Details below:

Q = MCΔT

Q = 100 × 4.184 × 2.9

Q = 1213.36 J

Finally, we shall determine the mass of the silver block. Details below:

Q = MCΔT

-1213.36 = M × 0.235 × -27.2

-1213.36 = M × -6.392

Divide both sides by -6.392

M = -1213.36 / -6.392

M = 189.8 g

Thus, we can conclude that the mass of the silver block is 189.8 g

Learn more about mass:

https://brainly.com/question/1674804

#SPJ1

Complete question:

A silver block, initially at 55.1∘C, is submerged into 100.0 g of water at 25.0∘C in an insulated container. The final temperature of the mixture upon reaching thermal equilibrium is 27.9∘C. The specific heat capacities for water and silver are Cs,water = 4.18J/(g⋅∘C) and Cs, silver = 0.235J/(g⋅∘C). What is the mass of the silver block?

Answer:

9.98%

Explanation:

To find the percent of NaCl in the mixture, we need to divide the mass of NaCl by the total mass of the mixture, and then multiply by 100 to express it as a percentage.

Step 1: Find the total mass of the mixture

total mass = mass of NaCl + mass of water

total mass = 23.5 g + 212 g

total mass = 235.5 g

Step 2: Calculate the percent of NaCl

% NaCl = (mass of NaCl / total mass) x 100

% NaCl = (23.5 g / 235.5 g) x 100

% NaCl = 0.0997876857 x 100

% NaCl = 9.978768677%

% NaCl = 9.98%

Therefore, the percent of NaCl in the mixture is 9.98%.

The given answer statement  "there is no aluminum left" and " limiting reactants is aluminum" are correct.

In the analysis of Trial 2, it was found that there was no aluminum left after the reaction had taken place. This indicates that all of the aluminum had reacted with the copper (II) chloride and that it was the limiting reactant in the reaction.

To confirm this, the mass of each reactant was converted to moles using their respective molar masses. It was found that the aluminum had a smaller number of moles than the copper (II) chloride, indicating that it would be used up first and thus be the limiting reactant.

Therefore, the limiting reactant in Trial 2 was aluminum.

To learn more about limiting reactants  here

https://brainly.com/question/14225536

#SPJ1

Since the ΔH for the given reaction has negative value, the reaction is exothermic reaction.

A reaction that is exothermic is one in which power is given off as heat or light. In contrast to an endothermic process, which draws energy from its surroundings, an exothermic reaction transfers energy into the environment. The alteration in enthalpy (H) during an exothermic reaction will be negative. Since the ΔH for the given reaction has negative value, the reaction is exothermic reaction.

To know more about exothermic reaction, here:

https://brainly.com/question/10373907

#SPJ1

The solution has a total volume of 300 mL and is composed of 100 mL of ethanol (the solute) and 200 mL of water (the solvent).

Less than 100 ml will result from mixing 50 ml each of ethanol and water in an equal ratio. This happens because ethanol molecules, which are smaller than those of water, may fit inside big water molecules. As a result, the alcohol content in a 250 mL mix of water and alcohol is 60%.

The combined volumes of the ethanol and water make up the total volume of the solution, which is:

Total volume = 100 mL + 200 mL = 300 mL

Therefore, the solution is made up of 100 mL of ethanol (the solute) and 200 mL of water (the solvent), with a total volume of 300 mL.

To know more about solution visit:-

https://brainly.com/question/30665317

#SPJ1

3.09 g is the theoretical mass of AlBr₃(s) produced.

The following dimensional analysis setup could be used to determine the theoretical mass of AlBr₃(s) (molecular mass = 266.69 g/mol) produced based on reacting 84.2 g of a 0.005 mol/L solution of Br₂(l) (density=1019 g/L) with excess Al(s) as described in the following equation:

3Br₂(l) + 2Al(s) → 2AIBr₃(s)

The dimensional analysis setup to calculate the mass of AlBr₃(s) produced is as follows:

84.2 g Br₂ (l) × (1 L solution / 1019 g Br₂(l)) × (0.005 mol Br₂(l) / 1 L solution) × (2 mol AlBr₃(s) / 3 mol Br₂(l)) × (266.60 g AlBr₃(s) / 1 mol AlBr₃(s)) = 3.09 g AlBr₃(s)

Therefore, the theoretical mass of AlBr₃(s) produced is 3.09 g.

Find out more on dimensional analysis here: https://brainly.com/question/24514347

#SPJ1

Answer:

Na < Al < Mg < S < Cl

Explanation:

Sodium has the smallest ionization energy because it wants to lose an electron as an alkali metal.

Aluminum has the second smallest because losing an electron would leave it with just a full s orbital.

Magnesium has the third smallest because although it's removing an electron from a full s orbital, it has less protons than sulfur and chlorine to keep the electron in the shell.

Sulfur has the second largest because it has more protons to pull at the electrons.

Chlorine has the largest ionization energy because it really wants an electron to fill the p orbital. Due to its number of protons, the element is also very small and it will be difficult to remove an electron.

b. To determine the number of joules of energy for the slice of cake, we need to convert the calories to joules using the conversion factor 1 calorie = 4.184 joules:

Number of joules = 560 calories * 4.184 joules/calorie = 2343.04 joules

Therefore, the slice of cake contains 2343.04 joules of energy.

c. To determine the number of kilojoules of energy for the slice of cake, we can divide the number of joules by 1000:

Number of kilojoules = 2343.04 joules / 1000 = 2.34304 kilojoules

Therefore, the slice of cake contains 2.34304 kilojoules of energy.

To determine the number of calories in 1.5 kilojoules of energy, we need to convert kilojoules to calories using the conversion factor 1 kilojoule = 1000 calories:

Number of calories = 1.5 kilojoules * 1000 calories/kilojoule = 1500 calories

Therefore, 1.5 kilojoules of energy contains 1500 calories.

Explanation:

Answer:

2. a. 560 Calories, b. 2343.04 J, c. 2.34304 kJ

3. 358.508604 Cal

Explanation:

2.

a. The number of calories found in the slice of chocolate cake is 56012.

b. To determine the number of joules of energy for the slice of cake, we can use the conversion factor that 1 calorie is equal to 4.184 joules3. Therefore, the number of joules in the slice of cake is:

560 Cal ⋅ 4.184 J/ 1 Cal = 2343.04J

c. To determine the number of kilojoules of energy for the slice of cake, we can use the conversion factor that 1 kilojoule is equal to 1000 joules4. Therefore, the number of kilojoules in the slice of cake is:

2343.04 J ⋅ 1 kJ/1000 J = 2.34304 kJ

3. To determine the number of calories in 1.5 kilojoules of energy, we can use the conversion factor that 1 kilojoule is equal to 239.005736 calories1. Therefore, the number of calories in 1.5 kilojoules of energy is:

1.5 kJ ⋅ 239.005736 Cal / 1 kJ = 358.508604 Cal

Answer:

a. Cl2 (g) + 2NaI (aq) → 2NaCl (aq) + I2 (s)

b. 2NaClO3 (s) → 2NaCl (s) + 3O2 (g)

c. 2K (s) + 2H2O (l) → 2KOH (aq) + H2 (g)

Explanation: