I NEED HELP! CHEMISTRY! PLEASE HELP ME!

Procedures:
Measure the mass of 2.5 mL of Lye (or ½ teaspoon of powdered lye)
If your scale is not accurate you can find the mass of a larger volume such as 25 mL and divide by 10.
Add 100.0 mL (½ cup) of vinegar to the calorimeter.
Measure the temperature of the vinegar (initial temperature)
Add 2.5 mL of Lye to the vinegar and record the highest temperature reached (final temperature).
Calculate the heat of this reaction, ∆H, using q = mc∆T (use the calculation steps below). ∆H = q
Determine the ∆H/mole of NaOH.

Your observations include the pertinent data and calculations from your experiment.

Record your observations here:
Specific heat of vinegar (c): 4.1 J/g oC
Density of vinegar: 0.99 g/mL

Mass of 2.5 mL (or ½ teaspoon) of lye:
Volume of vinegar:
Initial temperature of vinegar:
Final temperature of vinegar:

Energy gained by the contents of the calorimeter (q) = heat of the reaction (∆H)
q = mc∆T

Mass of 100.0 mL of vinegar (multiply by density of vinegar):

Mass of contents (vinegar + lye); this is m in our equation:

Change in temperature (Final – Initial), this is ∆T in our equation:

Energy gained by the calorimeter contents (this is q):

Moles of NaOH (assumes all of the lye is NaOH):

Value of ∆H in J/mole ( q / moles of NaOH):

The mass, in grams, of SO₃ in 1.00 L of the air sample is 27.48 g.

To determine the mass of SO₃ in 1.00 L of an air sample, we need to use the ideal gas law:

PV = nRT

where P is the partial pressure of SO₃, V is the volume of the sample (1.00 L), n is the number of moles of SO₃, R is the gas constant, and T is the temperature in Kelvin (308 K)

n = PV/RT

n = (8.75 torr) × (1.00 L) ÷ (0.0821 L·atm/mol·K) × (308 K)

n = 0.343 mol

To convert this to mass, we need to use the molar mass of SO₃, which is 80.06 g/mol. Therefore, the mass of SO₃ in 1.00 L of the air sample is:

mass = n × molar mass

mass = 0.343 mol × 80.06 g/mol

mass = 27.48 g

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Using the Clausius-Clapeyron equation, we can see that the new boling point is  34.6 K.

To calculate the boiling point of argon at 1.2 atm, we can use the Clausius-Clapeyron equation, which relates the boiling point of a substance at one pressure to its boiling point at another pressure, along with the latent heat of vaporization.

The Clausius-Clapeyron equation is given as:

ln(P1/P2) = ΔHvap/R * (1/T1 - 1/T2)

where:

Given:

We can rearrange the Clausius-Clapeyron equation to solve for T2 (the boiling point at 1.2 atm):

ln(P1/P2) = ΔHvap/R * (1/T1 - 1/T2)

Rearranging further:

1/T2 = (ln(P1/P2) * R) / ΔHvap + 1/T1

Plugging in the given values:

1/T2 = (ln(1 atm / 1.2 atm) * (8.314 J/(mol*K))) / (1.57 * 10^3 J/mol) + 1/21.9 K

Simplifying:

1/T2 = -0.0624 + 0.0456 + 0.0457

1/T2 = 0.0289

T2 = 1 / 0.0289

T2 = 34.6 K

That is the new one.

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Answer:

Therefore, the volume required at 600 atm and 0 °C is 0.319 L.

Explanation:

We can use the ideal gas law to solve for the number of moles of methane present, assuming ideal gas behavior at both conditions:

PV = nRT

At 300 atm and 200 °C:

n = PV/RT = (300 atm * 0.138 L) / [(0.08206 L atm mol^-1 K^-1) * (200 + 273.15) K * 1.067]

n = 2.451 mol

At 600 atm and 0 °C:

n = PV/RT = (600 atm * V2) / [(0.08206 L atm mol^-1 K^-1) * (273.15 K) * 1.367]

n = 7.682 V2

Since the number of moles of methane must be the same at both conditions:

2.451 mol = 7.682 V2

Solving for V2:

V2 = 0.319 L

Therefore, the volume required at 600 atm and 0 °C is 0.319 L.

To convert torr to kilopascals, we can use the following conversion factors:

1 torr = 1/760 atm

1 atm = 101.325 kPa

So, we can write: 656 torr × (1/760 atm) × (101.325 kPa/atm) = 87.0 kPa

Therefore, the atmospheric pressure during hurricane Patricia was 87.0 kPa.

Certainly!

In this exercise, converting a pressure value from torr to kilopascals (kPa) is required. Torr is a common unit of pressure used in physics and chemistry, while kPa is a common unit of pressure used in engineering and other disciplines.

We may utilise a conversion factor that connects torr to kPa to carry out the conversion. We must employ the following conversion factor:

0.133322 kPa per torr

As a result, 0.133322 kPa is equal to 1 torr. A pressure value in torr may be converted to a pressure value in kPa by multiplying the torr value by the conversion factor. This enables us to eliminate the torr units and obtain a value in kPa.

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To convert micrometers cubed (μm^3) to cubic centimeters (cm^3), we need to divide by 10^12 (since there are 10^12 μm^3 in 1 cm^3).

So, to convert 231 μm^3 to cm^3, we can use the following formula:

231 μm^3 ÷ (10^12 μm^3/cm^3) = 2.31 x 10^-10 cm^3

Therefore, 231 μm^3 is equal to 2.31 x 10^-10 cm^3.

:)

To convert micrometers cubed (μm^3) to cubic centimeters (cm^3), we need to divide by 10^12 (since there are 10^12 μm^3 in 1 cm^3).

So, to convert 231 μm^3 to cm^3, we can use the following formula:

231 μm^3 ÷ (10^12 μm^3/cm^3) = 2.31 x 10^-10 cm^3

Therefore, 231 μm^3 is equal to 2.31 x 10^-10 cm^3.

:)

The first ionisation energy increases over time from left to right among the major group of elements. answer is option (a).

When an element loses its valence electron, its oxidation number increases (a process known as oxidation), and this energy loss is known as ionisation (Ei).

Earth alkaline metals, which are located immediately next to alkaline metals, have higher ionisation energies than alkaline metals because they have two valence electrons, while alkaline metals, which are located far left in the main group, have the lowest ionisation energies and are easiest to remove.

Because they contain a large number of valence electrons, nonmetals are far to the right in the main group and have the highest ionisation energy.

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The complete question is,

Among the elements of the main group, the first ionization energy increases

a. from left to right across a period.

b. from right to left across a period.

c. when the atomic radius increases.

d. down a group.

The mass of butane, C₄H₁₀ needed to produce 70.8 g of carbon dioxide, CO₂ is 23.3 g

First, we shall write the balanced equation for the reaction. Details below:

2C₄H₁₀ + 13O₂ -> 8CO₂ + 10H₂O

From the balanced equation above,

352 g of CO₂ were obtained from 1 16 g of C₄H₁₀

Finally, we shall determine the mass of butane, C₄H₁₀ neeeded to produce 70.8 g of carbon dioxide, CO₂. Details below:

From the balanced equation above,

352 g of CO₂ were obtained from 116 g of C₄H₁₀

Therefore,

70.8 g of CO₂ will be obtain from  = (70.8 × 116) / 352 = 23.3 g of C₄H₁₀

Thus, the mass of butane needed is 23.3 g

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Answer: The molarity of the solution is 0.11 M.

Explanation: You first need to convert 65g of KCl to moles of KCl. When you do that you will get 0.871898055 moles of KCl, round anykind of answers you get at the end.

The second step is to use the molarity formula to find the molarity of the solution. Molarity = moles/liters

Molarity = 0.871898055 moles of KCl / 8.3 Liters of solution

M = 0.11

Make sure that your answer always has the correct number of significant figures. In the question both numbers given to you have 2 sig figs, therefore your final answer also needs to have 2 sig figs.

Answer:

Gold is the most malleable and ductile metal. It is soft and usually alloyed to give it more stability as it is easily bent. It is a great conductor of heat and electricity, but its greatest strength comes from the fact that does not react with oxygen. It is found that gold is unaffected by air, water, bases and most acids.

Okay, let's solve this step-by-step:

1) The standard reduction potentials for Cu2+/Cu are: E°Cu2+/Cu = +0.34 V.

This is the reduction potential when [Cu2+] = 1 M and [Cu] = 1 M.

2) The actual reduction potential (Ered) depends on the concentrations of oxidized and reduced species.

Here,

[Cu2+] = 4.48 M on the right side.

[Cu2+] = 0.0032 M on the left side.

3) Ered = E° + 0.0591 log([oxidized]/[reduced]) (Nernst equation)

So for the right side:

Ered = +0.34 + 0.0591 log(4.48/1) = +0.34 + 0.186 = +0.526 V

And for the left side:

Ered = +0.34 + 0.0591 log(0.0032/1) = +0.34 - 0.093 = +0.247 V

4) The cell potential (Ecell) is the difference between the two half-cell potentials:

Ecell = +0.526 - 0.247 = +0.279 V

So the cell potential for the given reaction at 25°C is +0.279 V.

Let me know if you have any other questions!

The net cell reaction is described by the equation: Pb(s) + PbO2(s) + 4H2SO4(aq) 2PbSO4(s) + 2H2O(l). 2.14 V and -0.36 V, respectively, are the standard potentials for the oxidation and reduction half-reactions. The result is that cell = 2.50 V.

The computed value of rxn is 2.50 V, which is the difference between the two standard potentials. The computed cell potential with [H2SO4] = 10.0 M at 25 C is 2.50 V. Six lead-acid cells connected in series make up a 12 V automobile battery.

Six cells are required to obtain 12 V because each cell has a voltage of 2.0 V. Consequently, there are six lead-acid cells in a 12 V automobile battery.

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To calculate the molecular weight of a substance from its vapor density, we can use the following formula:

Molecular weight = (RT/P) x d

where:

R is the gas constant (0.0821 L atm/mol K)

T is the temperature in Kelvin

P is the pressure in atm

d is the vapor density (in g/L) of the substance

First, we need to calculate the vapor density of the substance using the given information. We can use the ideal gas law to find the number of moles of the substance in the flask:

PV = nRT

where:

P is the pressure (687 mmHg = 0.903 atm)

V is the volume (100 mL = 0.1 L)

n is the number of moles of gas

R is the gas constant (0.0821 L atm/mol K)

T is the temperature in Kelvin (45°C = 318 K)

Solving for n, we get:

n = PV/RT = (0.903 atm)(0.1 L)/(0.0821 L atm/mol K)(318 K) = 0.00372 mol

Next, we can use the mass and volume information to find the density of the substance:

density = mass/volume = 1.22 g/0.1 L = 12.2 g/L

Since the vapor density is half of the density of the substance in the liquid state, we can calculate the vapor density:

vapor density = density/2 = 6.1 g/L

Finally, we can use the formula above to find the molecular weight:

Molecular weight = (RT/P) x d

Molecular weight = (0.0821 L atm/mol K)(318 K)/(0.903 atm) x 6.1 g/L

Molecular weight = 92.2 g/mol

Therefore, the molecular weight of the substance is 92.2 g/mol.

Depending on the pH of the solution, the surface charge of each nanocrystal, and the mixing of these two types of nanocrystals, complicated interactions may occur.

Friction is the most significant characteristic of nano metals. One of the many characteristics that make nanomaterials special is their small size. Nanomaterials can have a size up to a thousand times smaller than a human hair. The ratio of a nanoparticle's surface area to volume is very high.

Because of their distinct surface charges, these two different kinds of nanocrystals may exhibit electrostatic attraction or repulsion when combined in different pH environments. Positively charged nanocrystals with carboxylic acid caps may draw negatively charged ones with amine caps when the pH is low. The carboxylic acid-capped nanocrystals have a greater negatively charged surface charge when the pH rises, which may cause them to reject one another. The amine-capped nanocrystals, on the other hand, have a higher positive change in surface charge, which could cause them to attract.

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Sublimation and the coma is the only part of the comet that exists when it is further than 5 A.U from the sun.

Generally by the time that the comet comes within about 5 AU of the Sun, sublimation has generally formed a noticeable atmosphere that can easily escape the comet's weak gravity. The coma basically forms as the escaping atmosphere which drags away dust particles that have been mixed with the sublimating ice.

Generally when a comet is at a great distance away from the Sun, it exists as a dirty snowball several kilmometers across. But when it comes closer to the Sun, the warming of its surface causes its materials to melt and vaporize which produces the comet's characteristic tail.

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Eruption triangulation is a method for locating an earthquake's epicenter.

The area right above the spot in the Earth's crust where an earthquake originates or begins is known as the epicenter. It marks the spot on the Earth's surface where the earthquake's seismic waves first touchdown.

The distance between the earthquake's epicenter and a number of seismograph stations is calculated using seismograms, which are records of the ground motion brought on by an earthquake.

The following are the steps to find an earthquake's epicenter:

A minimum of three separate seismograph stations should have data collected. The epicenter's distance from each station is determined by keeping track of the time the earthquake waves arrived at each station.

Map out the positions of each seismograph station.

Draw circles with an equal radius around each seismograph station using the distance information. Each circle's radius is equal to how far away the station is from the epicenter.

At the place where the circles converge, there is an epicenter.

It is crucial to keep in mind that determining the epicenter of an earthquake is not an exact science, and the precision of the position will vary depending on a number of variables, such as the caliber of the seismograms and the distance between the earthquake and the seismograph stations.

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hope it helps:)

[tex]a. \: Ca + Cl _{2} → CaCl _{2} \\

\\ b. \: Cl _{2}+H _{2} O+ NaOH → \\ NaCl+ H _{2}O \\ \\

c. \: \: \: H _{2} SO _{4} +CaCO _{3} → \\ CaSO _{4} +H _{2}O+CO _{2} \\ \\

d. \: \: Fe+Cu(NO _{3}) _{2} → \\ Fe(NO _{3} ) _{2}+Cu[/tex]

brainliest pls ｡◕‿◕｡

Answer: The mass in grams is 290g.

Explanation: In order to find the mass you need to multiply the number of moles given by the molar mass of the compound.

You find the molar mass by adding all the atomic masses of each atom in the compound.

Since 0.75 has 2 significant figures, your final answer also needs to have 2 sig figs.

Answer:

If a solution appears red, it is most likely that green light is being absorbed the strongest. When light passes through a solution, the solution absorbs certain colors of light while allowing others to pass through. The color that we see is the color that is not absorbed and is transmitted through the solution. In the case of a red solution, red light is transmitted while green light is absorbed. This selective absorption of light is due to the specific chemical composition of the solution.

Lavoisier has been considered by many scholars to be the father of chemistry. Chemists continued to discover new compounds in the 1800s. The science also began to develop a more theoretical foundation. It was in 1807, John Dalton put forth his atomic theory.

It was not until the era of the ancient Greeks that we have any record of how people explained the chemical changes they observed and used. At that time natural objects were thought to consist of only four basic elements like earth, air, fire and water.

It was in the fourth century BC, two Greek philosophers Democritus and Leucippus suggested that matter was not infinitely divisible into smaller particles but instead consists of the fundamental particles called the atoms. Chemistry took its present form in the 18th century.

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The temperature inside the freezer is approximately -164°C.

To solve this problem, we can use the combined gas law equation:

[tex](P1V1)/T1 = (P2V2)/T2[/tex]

where P is the pressure, V is the volume, and T is the temperature of the gas.

We know that the initial volume of the balloon is 145 mL and the final volume is 35 mL. We also know that the initial temperature is 25°C or 298 K, and we need to find the final temperature.

Assuming the pressure of the gas remains constant, we can rearrange the combined gas law equation to solve for the final temperature:

[tex]T2 = (P2V2/T1)(P1/V1)[/tex]

Plugging in the values we know, we get:

[tex]T2 = (1 atm * 35 mL/298 K)(1 atm/145 mL) = 0.0808 atm/mL[/tex]

Multiplying both sides by 298 K and dividing by 0.0808 atm/mL, we get:

T2 = 109.15 K or approximately -164°C

Therefore, the temperature inside the freezer is approximately -164°C.

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The reaction between N2O4 and is at equilibrium at this time.2 Given by K = 0.028 is NO2. The amount of NO2 in the sample is 0.042 M.

K = [NO2] is the equilibrium expression for the reaction.²/[N₂O₄] When K and [NO2] are substituted in the equilibrium expression, we obtain 0.028 = (0.042).²/[N₂O₄]

We get at [N2O4] = 0.028/0.0422 = 0.0075 M after solving for [N2O4].

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From the balanced chemical equation we can see tha the mass of water produced is 2.47 grams.

The balanced chemical equation for the reaction between hydrochloric acid (HCl) and magnesium hydroxide (Mg(OH)2) is:

2 HCl + Mg(OH)2 → MgCl2 + 2 H2O

From the equation, we can see that 2 moles of hydrochloric acid react with 1 mole of magnesium hydroxide to produce 2 moles of water. To calculate the mass of water produced, we need to determine the limiting reactant, which is the reactant that is completely consumed first and determines the amount of product formed.

First, let's calculate the number of moles of each reactant:

Mass of HCl = 5.0 g

Molar mass of HCl = 36.46 g/mol

Number of moles of HCl = 5.0 g / 36.46 g/mol = 0.137 mol

Mass of Mg(OH)2 = 24.0 g

Molar mass of Mg(OH)2 = 58.33 g/mol

Number of moles of Mg(OH)2 = 24.0 g / 58.33 g/mol = 0.411 mol

According to the balanced chemical equation, 2 moles of HCl react with 1 mole of Mg(OH)2 to produce 2 moles of water. Therefore, the stoichiometry of the reaction requires 2 moles of HCl for every 1 mole of Mg(OH)2. Since we have only 0.137 mol of HCl and 0.411 mol of Mg(OH)2, the HCl is the limiting reactant because it is completely consumed first.

The molar ratio of HCl to water is 2:2, which simplifies to 1:1. Therefore, the number of moles of water produced is also 0.137 mol.

Now, let's calculate the mass of water produced using the molar mass of water:

Molar mass of water (H2O) = 18.02 g/mol

Mass of water produced = 0.137 mol x 18.02 g/mol = 2.47 g

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The stoichiometric ratio of NaHCO₃ to CH₃COOH, which is determined by the balancing equation, is 1:1, meaning that 1 mole of NaHCO₃ reacts with 1 mole of CH₃COOH.

Acetic acid (CH₃COOH), a component of vinegar, interacts with sodium bicarbonate (NaHCO₃) in baking soda to produce water, carbon dioxide gas, and sodium acetate.

CO₂(g) + H₂O(l) + NaC₂H₃O₂ = NaHCO₃(aq) + HC₂H₃O₂(aq) when yellow bubbles appear, an acidic gas H₂CO₃ has generated as a result of the reaction between CO₂ and water. The salt in the solution (NaC₂H₃O₂) is basic since the solution is red in colour.

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when a sufficient [tex]FeBr_{2[/tex] solution is introduced to 58.9 mL of 0.505 M [tex]Pb(NO_3)_2[/tex] solution, 5.45 grammes of [tex]PbBr_2[/tex] will precipitate.

We can figure out the amount of lead(II) bromide (PbBr2) that will precipitate by using the stoichiometry of the reaction between lead(II) nitrate [tex]Pb(NO_3)_2[/tex] and iron(II) bromide [tex](FeBr_2).[/tex]

The reaction's chemically balanced equation is as follows:

[tex]PbBr_2(s) + 2 Fe(NO_2)2 = Pb(NO_2)2(aq) + 2 FeBr_2 (aq)(aq)[/tex]

According to the equation, two moles  [tex]FeBr_2[/tex] react with one mole of [tex]Pb(NO_3)_2[/tex] to create one mole [tex]FeBr_2[/tex]. The amount  [tex]PbBr_2[/tex] that will precipitate will therefore be equal to half of the amount of [tex]Pb(NO_3)_2[/tex] that is present in the solution.

We can use the following formula to get the amount of[tex]Pb(NO_3)_2[/tex] in moles:

moles = volume x concentration

where volume is given as 58.9 mL, which we will divide by 1000 to get litres, and concentration is given as 0.505 M:

[tex]moles of Pb(NO3)2 = 0.505 M x 0.0589 L = 0.0297 moles[/tex]

Therefore, the amount of PbBr2 that will precipitate is:

[tex]PbBr2 moles =0.0297 moles / 2 moles, or 0.01485 moles.[/tex]

Finally, using the molar mass of [tex]PbBr_2[/tex], which is 367.01 g/mol, we can convert the number of moles  [tex]PbBr_2[/tex] to grammes:

[tex]mass of PbBr2 = 0.01485 moles x 367.01 g/mol = 5.45 g[/tex]

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The cell potential (Ecell) at 25°C (298 K) for the given reaction is 1.065 V which means that the reaction is spontaneous because the calculated Ecell is positive

The cell potential (Ecell) for the given reaction can be calculated using the Nernst equation:

Ecell = E°cell - (RT ÷ nF) × ln(Q)

where E°cell = standard cell potential, R = gas constant, T = temperature in Kelvin, n = number of electrons transferred in the reaction, F = Faraday constant, and Q is the reaction quotient.

Since two electrons are transported in the half-reactions, n in this instance equals 2. With the help of the species concentrations, it is possible to determine the reaction quotient Q:

Q = [Fe2+] ÷ [Cu2+]

Q = 0.645 ÷ 0.064

Q = 10.078

Now, we can calculate the Ecell:

Ecell = E°cell - (RT ÷ nF) × ln(Q)

Ecell = (0.337 - (-0.440)) - (8.31 × 298 ÷ (2 × 96500)) × ln(10.078)

Ecell = 1.065 V

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Intermolecular force connects atoms in different molecules. Intermolecular forces determine physical qualities including boiling temperature, melting point, viscosity, and surface tension.

London dispersion, dipole-dipole, and hydrogen bonding are intermolecular forces. London dispersion forces, caused by electron movement-induced dipoles, are the smallest intermolecular interactions between all atoms and molecules.

Polar molecules have greater dipole-dipole interactions than London dispersion forces. Hydrogen bonding is a specific dipole-dipole interaction between a hydrogen atom bound to an electronegative atom (N, O, or F) in one molecule and an electronegative atom in another molecule.

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1) The last state of matter we will study is gases.

a) P for Pressure which is often measured in units of atmospheres (atm), milliamps (mm Hg), pounds per square inch (psi), pascals (Pa)

b) V for Volume which is often measured in units of liters (L), cubic meters (m3), cubic feet (ft3), cubic inches (in3)

c) T for Temperature which must be in units Kelvin (K) or Celsius (°C).

d) n for Number of moles , which is often found by converting from grams of a gas.

100 mL of 3 M HCl can be neutralized with exactly 200 mL of 1.5 M NaOH. If this reaction is done in a coffee cup calorimeter, temperature would increase.

A chemical reaction known as neutralisation occurs when an acid and a base quantitatively react with one another. Alternate spellings include Neutralisation. The pH in the neutralised solution is determined by the acidity of the reactant.

Have you ever overindulged in spicy food and felt your stomach start to burn? This results from the stomach producing acid. The use of an antacid, which counteracts the effects of acid, can solve this issue; this process is known as a neutralisation response. 100 mL of 3 M HCl can be neutralized with exactly 200 mL of 1.5 M NaOH. If this reaction is done in a coffee cup calorimeter, temperature would increase.

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Explanation:

Only protons and electrons contribute to the charge of an atom ...NEUTRons are NEUTRal...

Protons are    + charge  

Electrons are  - charge

21 negative charges added to 17 positive charges results in

   - 4  charge