Today's lunch is related to your overall diet in the same way that today's weather is related to ______________.
A. Precipitation

B. Climate

C. The atmosphere

D. The water cycle

Answer:

i would say deposition

Answer: -345.2 KJ

Explanation: As we know that ,dG=dH-TdS

T=25+273=298 K

dG= -356 x1000-298(-36)= -356000+10728

=-345272 j

= -345.2 KJ

Answer:

Volume of the gas under STP is 84.7 mL.

Assumption: the gas is ideal.

Explanation:

How many moles of particles in this gas?

Convert all units to SI units before applying the ideal gas law.

The ideal gas constant: [tex]R \approx \rm 8.314\;Pa\cdot m^{3}\cdot K^{-1}\cdot mol^{-1}[/tex].

The ideal gas law:

[tex]P \cdot V = n \cdot R\cdot T[/tex]

Rearrange the ideal gas law to find the number of moles of particles [tex]n[/tex] in this gas:

[tex]\displaystyle n = \frac{P\cdot V}{R\cdot T} = \frac{5.39\times 10^{4}\times 1.80\times 10^{-4}}{8.314\times 308.65} = \rm 3.78081\times 10^{-3}\;mol[/tex].

The volume of one mole of an ideal gas under STP is 22.4 liters. The volume of [tex]\rm 3.78081\times 10^{-3}\;mol[/tex] of gas will be:

[tex]\rm 3.78081\times 10^{-3}\;mol\times 22.4\;L\cdot mol^{-1} = 0.0846901\;L = 84.7\; mL[/tex].

All three values in the question come with three significant figures. Keep more significant figures than that in calculations and round the final answer to three significant figures. Hence the answer: 84.7 mL.

Answer:

The answer to this question is heptane.

Explanation:

The name of the molecule will be 6-ethyl octan-2-ene.

6-ethyl octan-2-ene is kind of organic molecule in which 8 carbon atom is exit. At C-6 carbon ethyl group is attached.

A molecule would be a collection of two and more components bound atoms, whether they are from an identical element or another.

It can be seen that the longest chain of the molecule is C-8 and at C-2 carbon atom double bond is present . So it can be named as octan-2-ene . Due to the attachment of ethyl group with C-6 carbon atom it will be name as 6-ethyl octan-2-ene

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Answer:

= 0.00325 moles of beryllium

Explanation:

Molarity or concentration is given by the formula;

Molarity = Number of moles/Volume in L

Therefore, to get the number of moles

Moles = Molarity × Volume

           = 0.025 M × 0.13 L

           = 0.00325 moles of beryllium

Answer:

d) non-renewable resources

Explanation:

A natural resource such as coal, gas, or oil that, once consumed, cannot be replaced. Most energy resources currently in use are non-renewable while the renewable ones (such as wind and solar power) are not well developed. Also called depletable resource.

Answer: Non renewable resources.

Explanation: The non renewable resources can be defined as the resources that once used cannot be replenished. The resources like oil and copper takes very long time to form and this makes it non-renewable.

The natural resources like oil takes a long time to form inside the ocean and its extraction is also done after long time because its formation takes time.

Answer:

0.16 rounded

Explanation:

I used a calculator to get this answer, one that compared grams and mol.

The mass of 0.000142 mole of vitamin C is approximately 0.025 grams. This is derived by multiplying the number of moles by the molar mass of vitamin C, which is 176.124 g/mol.

The mass in grams of 0.000142 mole of vitamin C can be calculated by using the formula:

Mass (grams) = number of moles x molar mass (g/mol)

Calculating the Mass of Vitamin C

We have 0.000142 mole of vitamin C, and the molar mass of vitamin C (ascorbic acid) is 176.124 g/mol. By multiplying these values, we get:

Mass = 0.000142 moles x  176.124 g/mol = 0.025010168 grams

Therefore, the mass of the recommended daily dietary allowance of vitamin C for children aged 4-8 years is approximately 0.025 grams.

Answer:

[tex]\boxed{\text{9.170 m}}[/tex]

Explanation:

The pressure p exerted by a column of liquid is given by the formula  

p = hρg

where

h = height of column

ρ = density of liquid

g = acceleration due to gravity

Data:

p = 1 bar = 100 kPa = 10⁵ N·m⁻² = 10⁵ kg·m⁻¹s⁻²

ρ = 1.112 g·cm⁻³ = 1112 kg·m⁻³

g = 9.807 m·s⁻²

Calculation:

10⁵ = h × 1112 × 9.807

10⁵ = 1.091 × 10⁴ h

h = 9.170 m

[tex]\text{The height of a column of ethylene glycol that would be supported by an}\\\\\text{atmospheric pressure of 1 bar is }\boxed{\textbf{9.170 m}}[/tex]

Answer:

A large plateau forms in the interior of a continental plate when a large section of the plate rises evenly due to an even expansion of the underlying mantle. B.

Answer: Option (A) and (D)

Explanation: Epeirogenic process refers to the uplifting and sinking of the continental crust. It is the vertical movement of the crust due to certain mechanisms. Divergent movement of the plates leads to the thinning of the crust and in the convergent plate boundary between a continent and oceanic plate, creates an accretionary wedge that increases the vertical height of the crust. It is not related to the continental collision and plateaus are the stable part of the continent where there is not much change in the thickness of the crust.

Thus the correct answers are (A) and (D)

Answer:

4.5 L.

Explanation:

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R  is the general gas constant,

T is the temperature of the gas in K.

(P₁V₁) = (P₂V₂)

P₁ = 3.0 atm, V₁ = 1.5 L,

P₂ = 1.0 atm, V₂ = ??? L.

(P₁V₁) = (P₂V₂)

∴ V₂ = (P₁V₁)/P₂ = (1.5 L)(3.0 atm)/(1.0 atm) = 4.5 L.

So, the right choice is: 4.5 L.

Answer:

4.5 L.

Explanation:

Answer:  

--Acid is the substance when dissolved in water, increases the concentration of H+ ions.

--Such compound whose chemical formula begins with H, for example HCl (Hydrochloric acid), H3BO3 (Boric acid), CH2O3 (Carbonic

acid). Although CH3COOH (Acetic acid) is an exception.

--Its less than 7.

--Bases are the proton acceptor.

--Such compounds whose chemical formula ends with OH, for example KOH (Potassium hydroxide), NaOH (Sodium hydroxide).

--Its greater than 7.

Explanation:

One can distinguish between a strong acid and a strong base by using pH paper or a pH meter, observing the reaction in a neutralization process with known substances, and testing the conductivity of the solutions.

To distinguish between a strong acid and a strong base, one can use the following three safe methods:

It's important to handle all strong acids and bases with proper safety equipment and procedures due to their corrosive nature.

Answer:

A.

Explanation:

if it's the same element the protons will always be the same, but have different neutrons, and neutrons is made up of protons and atomic mass, which atomic mass numbers can be calculated different where in return gives different numbers of neutrons.

EX: say the element is carbon, carbon has 6 protons and that won't change, but carbon can have an atomic mass of 12, 13, or 14, etc. so when you make up the neutrons you add protons and atomic mass, 6 + 12 = 18 N

6 + 13 = 19 N

6 + 14 = 20 N

Isotopes of a given element have the same number of protons but vary in the number of neutrons. Therefore, option A: protons; neutrons is correct.

If two atoms are isotopes of the same element, they will have the same number of protons, but will have different numbers of neutrons. This is because all isotopes of an element will contain the same number of protons, which determines the atomic number and thus the identity of the element. However, isotopes differ in the number of neutrons in their atomic nuclei, which leads to differing atomic masses. Hence, the correct choice is A: protons; neutrons.

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Answer:

B) There is more water in the air because the rate of evaporation increases

Explanation:

As the temperatures rise across the globe, the rate of evaporation also increases, resulting in more water in the air. The reason for the increased evaporation is that the ice sheets and glaciers are melting, thus there's more liquid water. The more liquid water there is, the more evaporation there will be. As the evaporation increases, there will be an increase in the formation of clouds, thus there will be more precipitation around the world, gradually leading to warmer and wetter climate.

Answer:

An Arrhenius Base

Explanation:

The definition of this is a base that is a hydroxide ion donor.

A base is a substance that produces hydroxide ions in solutions.

A base that produces hydroxide ions in aqueous solution is also known as:  A. Arrhenius bases

An Arrhenius base is a compound that increases the OH− ion concentration in aqueous solution. The reaction between an Arrhenius acid and an Arrhenius base is called neutralization and results in the formation of water and a salt.

An Arrhenius base is a substrate that increases the concentration of hydroxide ions in the aqueous solution. The example for Arrhenius base is highly soluble sodium hydroxide compound in water, which dissociates to give sodium ion and hydroxide ion.

Other examples of Arrhenius acids include sulfuric acid (H2SO4), hydrobromic acid (HBr), and nitric acid (HNO3). Examples of Arrhenius bases include sodium hydroxide (NaOH) and potassium hydroxide (KOH).

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Answer:

a. 74.55 g/mol.

b. 91.70 g.

c. 8.40%.

d. 1.23 mol/L.

Explanation:

a. Calculate the formula weight of KCl.

∵ Formula weight of KCl = atomic weight of K + atomic weight of Cl

atomic weight of K = 39.098 g/mol, atomic weight of Cl = 35.45 g/mol.

∴ Formula weight of KCl = atomic weight of K + atomic weight of Cl = 39.098 g/mol + 35.45 g/mol = 74.548 g/mol ≅ 74.55 g/mol.

b. Calculate the mass of KCl in grams.

no. of moles (n) = mass/molar mass.

∴ mass of KCl = n*molar mass = (1.23 mol)*(74.55 g/mol) = 91.69 g ≅ 91.70 g.

c. Calculate the percent by mass of KCl in this solution.

The mass % of KCl = (mass of KCl/mass of the solution) * 100.

mass of KCl = 91.70 g,

mass of the solution = 1000.0 g of water + 91.70 g of KCl = 1091.70 g.

∴ The mass % of KCl = (91.70 g/1091.70 g)*100 = 8.399% ≅ 8.40%.

d. Calculate the molarity of the solution.

Molarity is the no. of moles of solute per 1.0 L of the solution.

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

no. of moles of KCl = 1.23 mol,

Volume of the solution = mass of water / density of water = (1000.0 g)/(1.00 g/mL) = 1000.0 mL = 1.0 L.

M = (1.23 mol)/(1.0 L) = 1.23 mol/L.

a. The formula weight of KCl is 74.55 g/mol. b. The mass of KCl in grams is 91.39 g. c. The percent by mass of KCl in the solution is 9.14%. d. The molarity of the solution is 1.23 M.

a. The formula weight of KCl (potassium chloride) can be calculated by summing the atomic masses of potassium (K) and chlorine (Cl). The atomic mass of K is 39.10 g/mol and the atomic mass of Cl is 35.45 g/mol. Therefore, the formula weight of KCl is 39.10 g/mol + 35.45 g/mol = 74.55 g/mol.

b. To calculate the mass of KCl in the solution, we need to convert the given amount of KCl in moles to grams. Since 1 mole of KCl has a mass of 74.55 g (as calculated in part a), 1.23 mol of KCl will have a mass of 1.23 mol x 74.55 g/mol = 91.39 g.

c. The percent by mass of KCl in the solution can be calculated by dividing the mass of KCl (91.39 g, as calculated in part b) by the mass of the solution and multiplying by 100%. The mass of the solution is given as 1000.0 g. Therefore, the percent by mass of KCl in the solution is (91.39 g / 1000.0 g) x 100% = 9.14%.

d. The molarity of the solution can be calculated by dividing the number of moles of KCl by the volume of the solution in liters. The number of moles of KCl is given as 1.23 mol and the volume of the solution is 1000.0 g of water, which is equivalent to 1000.0 mL or 1.0000 L. Therefore, the molarity of the solution is 1.23 mol / 1.0000 L = 1.23 M.

Answer:

108.9 L.

Explanation:

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

(P₁V₁) = (P₂V₂).

P₁ = 125 mm Hg, V₁ = 136.5 mL,

P₂ = 156.7 mm Hg, ​V₂ = ??? mL.

∴ V₂ = (P₁V₁)/(P₂) = (125 mm Hg)(136.5 mL)/(156.7 mm Hg) = 108.9 L.

Answer:

37.25 grams/L.

Explanation:

M = (no. of moles of KCl)/(volume of the solution (L))

∵ no. of moles of KCl = (mass of KCl)/(molar mass of KCl)

∴ M = [(mass of KCl)/(molar mass of KCl)]/(volume of the solution (L))

∴ (mass of KCl)/(volume of the solution (L)) = (M)*(molar mass of KCl) = (0.5 M)*(74.5 g/mol) = 37.25 g/L.

So, the grams/L of KCl = 37.25 grams/L.

In a 0.5 M KCl solution, there are 0.5 moles of KCl per liter. Given the molecular weight of KCl is 74.5 g/mol, this would translate to 37.25 grams of KCl per liter.

If you have a 0.5 M KCl solution, this means that the concentration of KCl in the solution is 0.5 moles per liter. To find the amount of solute in moles, you would simply use the concentration of the solution and the volume of the solution. In this case, if you have a 1-liter solution, you will have 0.5 moles of KCl, since the concentration is 0.5 M.

To convert this amount in moles to grams, you will need to use the molecular weight of KCl, which is given as 74.5 g/mol. By multiplying the number of moles by the molecular weight, you get the grams of the solute:

0.5 moles × 74.5 g/mol = 37.25 grams of KCl

Therefore, in a 1-liter solution of 0.5 M KCl, you would have 37.25 grams of KCl.

Hello There!

The Answer Is In Image Provided.

Your Unit Is Still Kilometers

Answer:

The right choice is "burning gas → pan → water → eggs"

Explanation:

Heat will flow from the body of higher temperature to the cooler body.

So, heat will firstly flow from burning gas to pan by conduction then to the water in contact with pan then to the egg present inside the water.

So, the right choice is :

"burning gas → pan → water → eggs"

Answer: Option (c) is the correct answer.

Explanation:

When two objects of different temperature come in contact with each other then heat will flow from hot object to cold object. This process of transfer of heat is known as conduction.

For example, a pan of boiling  eggs on a gas burner will have transfer of heat from gas burner to the pan and then heat will flow from water to the eggs.

This process is also a conduction process.

Thus, we can conclude that the path of heat  flow will be as follows.

        [tex]\text{burning gas} \rightarrow \text{pan} \rightarrow \text{water} \rightarrow \text{eggs}[/tex]

Answer:

0.7692 M ≅ 0.77 M.

Explanation:

(MV) before dilution = (MV) after dilution.

M before dilution = 2.0 M, V before dilution = 0.25 L.

M after dilution = ??? M, V after dilution = 0.25 L + 0.40 L = 0.65 L.

∴ M after dilution = (MV) before dilution/(V) after dilution = (2.0 M)(0.25 L)/(0.65 L) = 0.7692 M ≅ 0.77 M.

Answer:

nano3 is a solid so its not that one it has to be NH3

Explanation:

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Final answer:

The substance among the given options that is a gas is NH3 or ammonia, as indicated by (g) for gaseous state in the provided reference list.

Explanation:

Among the substances listed — NaNO3, KL, KCL, and NH3 — the one that is a gas is NH3, also known as ammonia. From the reference information provided, NH3 is indicated as NH3(g), where (g) denotes that it is in the gaseous state at standard temperature and pressure. The other substances NaNO3, KL (which seems to be a typo and should likely be KI), and KCL (KCl) are solids as indicated by the (s) in the reference list provided.

NH3 is a common gas known for its pungent odor and is used in various applications, including household cleaning products and fertilizers.

Hopefully this is close to what you looking for

One way :

-Dawn soap

-some water

-Salt crystals

-Put in freezer for a few hours

-StarGaze

(if this doesn't work comment)

I suggest using a little bit first, to see if it works for you.

At the melting point. Draw a line up from 0 degrees and a line to the right from 1 atm. They meet at the line between solid and liquid... the melting point

Answer: it's boiling point!

Explanation:

Answer:

I believe two correct statements are;

The vapor pressure is produced by water molecules that have evaporated.

The vapor pressure increases as the Sun heats the water in the pot.

Explanation:

When an uncovered pot of water lies out in the sun then the vapor pressure is produced by water molecules that have evaporated and increases as the Sun heats.

Vapor pressure is a property of the substance which may change into gaseous state.

When an uncovered pot of water lies out in the sun, then the vapor pressure is produced by the water molecules of the surface phase and they get evaporated. And due to heat transfer by the sun in the form of sunlight vapor pressure of water also increases, which results into more evaporation.

Hence, option (2) and (3) is correct it means vapor pressure increases as the sun heats the water in the pot and they get evaporated.

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Answer:

0.218 mol.

Explanation:

CH₄ + 2O₂ → CO₂ + 2H₂O,

It is clear that 1 mol of CH₄ reacts with 2 mol of O₂ to produce 1 mol of CO₂ and 2 mol of H₂O.

n = mass/molar mass = (7.84 g)/(18.0 g/mol) = 0.436 mol.

Using cross multiplication:

1 mol of CH₄ is needed to produce → 2 mol of H₂O, from stichiometry.

??? mol of CH₄ is needed to produce → 0.436 mol of H₂O.

∴ The no. of moles of CH₄ = (1 mol)(0.435 mol)/(2 mol) = 0.218 mol.

Answer:

[tex]\boxed{\text{25 da}}[/tex]

Explanation:

Step 1. Convert pounds to milligrams

(a) Pounds to grams

[tex]\text{Mass} = \text{2 lb} \times \dfrac{\text{454 g}}{\text{1 lb}} = \text{910 g}[/tex]

(b) Grams to milligrams

[tex]\text{Mass} = \text{910 g} \times \dfrac{\text{1000 mg}}{\text{1 g}} = \text{910 000 mg}[/tex]

Step 2. Calculate the time

(a) Milligrams to minutes

[tex]t = \text{910 000 mg}} \times \dfrac{\text{20 min}}{\text{500 mg}} = \text{36 000 min}[/tex]

(b) Minutes to hours

[tex]t = \text{36 000 min} \times \dfrac{\text{1 h}}{\text{60 min}} = \text{610 h}[/tex]

(c) Hours to days

[tex]t = \text{ 610 h} \times \dfrac{\text{1 da}}{\text{24 h}} = \text{25 da}[/tex]

It will take [tex]\boxed{\textbf{25 da}}[/tex]to dissolve the iron oxide.

Answer : The time taken for the reaction is 36363.64 minutes.

Explanation :

First we have to convert the mass of iron oxide from milligram to pounds (lbs).

[tex]1\text{ lbs}=453592mg[/tex]

or,

[tex]1mg=\frac{1}{453592}\text{ lbs}[/tex]

As, [tex]1mg=\frac{1}{453592}\text{ lbs}[/tex]

So, [tex]500mg=\frac{500mg}{1mg}\times \frac{1}{453592}\text{ lbs}=0.0011\text{ lbs}[/tex]

Now we have to calculate the time taken for the reaction.

As, [tex]0.0011\text{ lbs}[/tex] of iron oxide take time = 20 minutes

As, [tex]2\text{ lbs}[/tex] of iron oxide take time = [tex]\frac{2\text{ lbs}}{0.0011\text{ lbs}}\times 20\text{ minutes}=36363.64\text{ minutes}[/tex]

Therefore, the time taken for the reaction is 36363.64 minutes.

Answer:

2,700 mmHg.

Explanation:

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

P₁V₁T₂ = P₂V₂T₁

P₁ = 760 mmHg, V₁ = 0.50 m³, T₁ = 33°C + 273 = 306.0 K.

P₂ = ??? mmHg, V₂ = 0.10 m³, T₂ = - 55°C + 273 = 218.0 K.

∴ P₂ = P₁V₁T₂/V₂T₁ = (760 mmHg)(0.50 m³)(218.0 K)/(0.10 m³)(306.0 K) = 2707.0 mmHg ≅  2,700 mmHg.

Answer:

2,700 mmHg.

Explanation:

Answer:

7366.328 kPa.

Explanation:

1.0 atm = 101.325 kPa.

The conversion factor = (101.325 kPa/1.0 atm)

∴ The critical pressure of carbon dioxide (in kPa) = (72.7 atm)(101.325 kPa/1.0 atm) = 7366.328 kPa.

Answer:

= 7366.328 kPa.

Explanation:

(72.7 atm)(101.325 kPa/1.0 atm)

= 7366.328 kPa.

The

balanced reaction is:

2LiOH + CO2 = Li2CO3 + H2O

We

are given the amount of the reactants to be reacted. This will be the starting point of our

calculations. To determine the limiting reactant, we convert the amounts from grams to moles.

1.000 × 10^3 g LiOH  (1 mol / 25.95 g) = 38.54 mol LiOH

8.80 × 10^2 g CO2 ( 1mol / 44.01 g) = 20.00 mol CO2

From the balanced reaction, the molar ratio of the reactants is 2:1. This means that every two mole of lithium hydroxide, 1 mole of carbon dioxide is needed. It is clear that, from the given amounts, CO2 is the limiting reactant.

Answer: The limiting reagent is carbon dioxide and theoretical yield of the reaction is 360 g.

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]      .....(1)

Given mass of LiOH = [tex]1.00\times 10^3g[/tex]

Molar mass of LiOH = 23.95 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of LiOH}=\frac{1.00\times 10^3g}{23.95g/mol}=41.75mol[/tex]

Given mass of carbon dioxide = [tex]8.8\times 10^2g[/tex]

Molar mass of carbon dioxide = 44 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of carbon dioxide}=\frac{8.8\times 10^2g}{44g/mol}=20mol[/tex]

[tex]2LiOH(s)+CO_2(g)\rightarrow Li_2CO_3(s)+H_2O(l)[/tex]

By Stoichiometry of the reaction:

1 moles of carbon dioxide reacts with 2 moles of lithium hydroxide.

So, 20 moles of carbon dioxide will react with = [tex]\frac{2}{1}\times 20=40mol[/tex] of lithium hydroxide.

As, given amount of lithium hydroxide is more than the required amount. So, it is considered as an excess reagent.

Thus, carbon dioxide is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

1 mole of carbon dioxide produces 1 mole of water

So, 20 moles of carbon dioxide will produce = [tex]\frac{1}{1}\times 20=20moles[/tex] of water

Molar mass of water = 18 g/mol

Moles of water = 20 moles

Putting values in equation 1, we get:

[tex]20mol=\frac{\text{Mass of water}}{18g/mol}\\\\\text{Mass of water}=360g[/tex]

Hence, the limiting reagent is carbon dioxide and theoretical yield of the reaction is 360 g.

Answer:

The second and third option are isotopes of Bromine

Z=  35 A = 79

A = 79  N= 44

Explanation:

Step 1: What are isotopes ?

⇒ Elements  with same atomic number (Z) ( this means the same number of electrons and protons) but a different number of neutrons (N)

The atomic number (visible on the periodic table) is the number of protons.

The atomic mass is  the sum of the protons (Z) and neutrons (N), and is showed as 'A'. So A = Z+N

If we look at the periodic table, we can see that the atomic number of bromine (Z) = 35. This means the amount of protons = 35. Since isotopes have the same amount of protons, all isotopes of bromine, have 35 protons.

1) Z = 79, A = 196

Z = protons = electrons .So this element has 79 protons, as well as 79 electrons.

196 = 79 + N ⇒ N = 196 - 79 = 117 neutrons

⇒Since it doesn't have 35 protons, it isn't an isotope of Bromine, but of Gold (Au): 196Au

2) Z = 35 , A = 79

Z = protons = electrons .So this element has 35 protons, as well as 35 electrons.

79 =35 + N ⇒ N = 79 - 35= 44 neutrons

⇒Since it does have 35 protons, it is an isotope of Bromine. This isotope has 44 neutrons

⇒ This is 79Br, which is a stable isotope of Bromine.

3) A=79, N = 44

Z = A - N ⇒ Z = 79 - 44 = 35

Z = protons = electrons .So this element has 35 protons, as well as 35 electrons. It also has 44 neutrons.

⇒Since it does have 35 protons, it is an isotope of Bromine, with 44 neutrons: 79Br

4) Z = 44, N = 44

Z = protons = electrons .So this element has 44 protons, as well as 44 electrons.

A = 44 + 44 ⇒ A = 88  

⇒Since it doesn't have 35 protons, it isn't an isotope of Bromine, but of Ruthenium (Ru) : 88Ru

⇔So the second and third option are isotopes of Bromine