If the caffeine concentration in a particular brand of soda is 3.55 mg/oz, drinking how many cans of soda would be lethal? Assume that 10.0 g of caffeine is a lethal dose, and there are 12 oz in a can.

Answer:

B is a precipitation reaction.

Explanation:

This is because a precipitation reaction is when a solid is made from the combination of cations and anions in a solution to create a solid.

[tex]\rm 2 NaI(aq) + Hg_2(NO_3)_2(aq) \rightarrow Hg_2I_2(s) + 2 NaNO_3(aq)[/tex] is a precipitation reaction. Therefore, the correct option is option B.

When two soluble compounds are combined, a precipitation reaction occurs, which is a sort of chemical reaction that creates an insoluble solid known as a precipitate. When two compounds mix to generate an insoluble compound that separates out as a solid from the solution, a precipitation reaction takes place.

The reactants in a precipitation reaction are typically ionic compound-containing aqueous solutions. The ions from the various chemicals may combine in these solutions to generate a complex that is only partially soluble. As a result, a solid precipitate that settles out of the solution is created. [tex]\rm 2 NaI(aq) + Hg_2(NO_3)_2(aq) \rightarrow Hg_2I_2(s) + 2 NaNO_3(aq)[/tex] is a precipitation reaction.

Therefore, the correct option is option B.

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Answer:

The answer to your question is: 303g of CO2

Explanation:

Data

mass CO2 = ?

mass C4H10 = 100 g

MW C4H10 = 58.12 g

MW CO2 = 44.01 g

Solve this problem using rules of three

Reaction

                    2 C4H10 (g) + 13 O2 (g) → 8 CO2 (g) + 10 H20 (l)

                    2(58.12)      ------------------ 8(44.01)

                    100g          -------------------    x

mass of CO2 produced = x = (100)(8)(44.01) / (2)(58.12)

                                          x = 35208 / 116.24

                                          x = 302.9 g ≈ 303 g of CO2

Answer:

C

Explanation:

Attached is the structure of a hydronium ion.

A is not the answer since evaporation is a phase change, not a structural change.  We are looking for a structural change since we are trying to form a hydronium ion.

B is not the answer since two water molecules bonded together would not produce the attached structure. It would produce a structure with two oxygens and four hydrogens.

C is the answer since water bonding to another hydrogen produces a hydronium ion.

D is not the answer since this combination would produce water.

E is not that answer since splitting a water molecule in half would take from the structure when you are actually supposed to add to it.

Answer:

Explanation:

To neutralize a chemical to a pH of 7 before discarding, one would require a significant amount of acids or bases. Our best guess is that the solution in itself is either an acid or a base. Neutralization with the right amount of a proper reagent can bring the pH of the solution to a neutral 7.

If the solution has a pH originally greater than 7, add a corresponding amount of acid to it. This will reduce the concentration and bring it to a neutral point. Provided one is dealing with a solution of pH less than 7, simply add a base to to bring the solution to neutrality.

Remember, the term pH (or pH value) is a standard measure of the level of acidity/basicity of a chemical solution. The pH value typically ranges from 0 to 14, where a solution with pH 7 is referred to as being neutral. While chemical solutions with pH values greater than 7 are base, meanwhile those lower than 7 indicate acidity.

In this instance, we want the chemical solution to become neutral (ie. to a have pH of 7). Logically this implies that this chemical solution should either be an acid or a base, but not neutral.

Scenario 1:

the chemical solution is a base, i.e it has pH values greater than 7: adding the right amounts of acid to the base should cause a reaction that would make the chemical solution neutral.

Scenario 2:

the chemical solution is an acid, i.e it has a pH lower than 7. In this case, adding the right amounts of a base solution to the acid should make neutrality.

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Answer:

6

Explanation:

The maximum number of electrons in the orbitals of sub-levels are given as:

   for s-sublevel we have two electrons and one orbital

        p-sublevel we have six electrons and three orbitals

        d-sublevel we have ten electrons and five orbitals

       f- sublevel we have fourteen electrons and seven orbitals

The second energy level is represented by the p-sub-level and it will accommodate 6 electrons.

Answer:

The correct answer for this one, is e. because CH2O is a chemical compound of the aldehyde type and the aldehydes are only at the monosaccharides (carbohydrates)

Explanation:

As you should know, amino acid contains a carboxyl group and an amino group, DNA it is compounded by  a pentose, nitrogen base and a phosphate group, the triglyreceride are  long chain fatty acid compounds, so much of CH2O. The proteins are very complex structures to have only those elements.

Answer:

E. monosaccharide

Explanation:

monosaccharides have this chemical formula: (CH2O)

This means 1 carbon, 2 hydrogen and 1 oxygen

The difference between measuring a foot as 27 centimeters and 27.00 centimeters is in the precision of the measurements. The first suggests an estimated measurement likely made with a standard ruler without fine markings, while the second implies a more exact measurement, possibly with a tool that includes millimeter markings.

The difference between the two measurements of a student's foot being 27 centimeters and 27.00 centimeters lies in the precision of the measuring instruments used. In the first measurement with 27 centimeters, only the whole numbers are reported, which suggests that the instrument used could have been a standard ruler that does not have detailed millimeter markings. Because of this, only the length in whole centimeters is certain, while the tenths place is estimated. In the second measurement of 27.00 centimeters, the inclusion of two decimal places indicates that a more precise measuring tool was used, likely one with millimeter (which are tenths of a centimeter) markings. This allowed the student to report the measurement with greater specificity, showing that the length is not just 27 centimeters, but 27.00 centimeters, where the trailing zeros indicate confidence in the measurement up to the hundredths place.

It is important to select the appropriate measuring tool for the precision required. For everyday measurements, a standard ruler might suffice, but for more precise measurements, a tool that provides readings in millimeters or even smaller units would be necessary.

Answer:

The answer to your question is: A. Has few interaction with water

Explanation:

As you can read in the question and see in the picture, phospholipid is formed by to parts:

A head that is polar, that means it prefer to interact with polar substances like water.

A tail: that is non polar, that means it doesn't interact with polar substances, then, they only interact with non polar substances.

In the cell membrane, the heads of the phospholipids are in the borders and the tails are inside. Membrane is like a sandwich where the breads would be the heads and the content (ham, etc) would be the tails.

The hydrophobic portion of a phospholipid has few interactions with water. Correct option is A.

The hydrophobic portion of a phospholipid refers to the nonpolar tail that is repelled by water and is therefore hydrophobic. This means that it has few interactions with water and prefers to be in a non-aqueous environment.

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Answer:

It is a law because it is a statement of fact that does not need any more experimental support.

Explanation:

A hypothesis is an acceptable assumption that is formulated through the collection of information and data and that attempts to explain some phenomenon. In other words, a hypothesis is a conjecture with which one tries to explain an observed fact. The formulation of a hypothesis can be derived in two different ways: by generalization, from a certain number of cases or observed phenomena; and, by analogies observed in the occurrence of different phenomena.

A theory is something that attempts to explain some phenomenon and that is accepted as true by the scientific community. In other words, a theory is a set of rules that describe the behavior of a particular system.

A law is a statement that expresses the constant relationships between phenomena of nature, society or the mind. Scientific law can be defined as an invariable relationship of terms. In other words, a law is what is scientifically proven to be true, it is universally applicable.

So scientific theories and scientific laws are based on hypotheses. But a theory is the explanation of an observed phenomenon, while a scientific law is the description of an observed phenomenon.

The movements of bodies in space are governed by Newton's Laws. These are laws why they are demonstrated by mathematical formulas and Universal application.

Then, the correct option is "It is a law because it is a statement of fact that does not need any more experimental support."

Answer:

D

Explanation:

I took a quiz

Answer:

The last reaction is an oxidation:

[tex]Cr_(_s_)~->~Cr^+3_(_a_q_)~+~3e^-[/tex]

Explanation:

For the first half-reaction, we have a strange reduction the charge is not balanced so, it is not a possible reaction. In the second half-reaction we will have a reduction process as such, we have 2 negative charges in both sides and the electrons are placed on the reactive side. For the third half-reaction, we will have strange oxidation because the charge is not balanced, we have a charge of +1 in the left and a charge of -1 in the right, so this is not a possible reaction. For the last half-reaction, we have the production of electrons and the charge is equal on both sides, which is zero.  

Finally to remember, Oxidation=production of electrons, Reduction=Consumtion of electrons.

Answer:

The answer to your question is: 24.31 amu

Explanation:

Magnesium isotopes      1  mass 23.99 abundance 78.99%

                                         2 mass 24.99    abundance    10.00%

                                        3  mass 25.98    abundance    11.01 %

Atomic mass of magnesium = ((23.99x0.7899) + (24.99 x 0.10) + (25.98x0.1101)

Atomic mass of magnesium = 18.95 + 2.5 + 2.86

Atomic mass of magnesium = 24.31 amu

The atomic mass of the magnesium atom can be calculated by adding the masses of isotopes. The atomic mass of magnesium element is 24.31 atomic mass units.

Atomic mass is the estimation of the number of neutrons and protons that can also be given as the average atomic mass that is given by the mass and the relative abundance of the isotopes.

Given,

Mass of Mg isotope 1 (M₁) = 23.99

Mass of Mg isotope 2 (M₂) = 24.99

Mass of Mg isotope 3 (M₃ ) = 25.98

Natural abundances of Mg isotope 1 (A) = 78.99%

Natural abundances of Mg isotope 2 (B) = 10.00%

Natural abundances of Mg isotope 2 (C) = 11.01%

The atomic mass of Mg is calculated as:

= (M₁ × A) + (M₂ × B) + (M₃ × C)

= ((23.99 × 0.7899) + (24.99 × 0.10) + (25.98 × 0.1101)

= 18.95 + 2.5 + 2.86

= 24.31 amu

Therefore, 24.31 amu is the atomic mass of magnesium.

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Answer:

C

Explanation:

The dependent variable is the variable that you measure and in this experiment, the amount of NaCl dissolved is what is being measured.

The correct answer is C. The amount of NaCl dissolved

Explanation:

In an experiment, you can identify the dependent variable because this is the factor tested or studied. Also, this variable is affected by the independent variable or factor manipulated by the scientists. This means, in the experiment presented, the independent variable is the temperature as this is manipulated, and therefore the dependent variable is the amount of NaCl dissolved because this depends on the independent variable and it is the main factor that is being tested.

Answer:

We also need the nitrogen intake

Explanation:

The nitrogen balance is the difference between the nitrogen intake and nitrogen excreted. If this calculation is positive, the body grow; if it is negative, the body is decreased.

Answer: The freezing point of a 0.765 m solution of nitrobenzene in naphthalene is [tex]74.6^0C[/tex]

Explanation:

Depression in freezing point is given by:

[tex]\Delta T_f=i\times K_f\times m[/tex]

[tex]\Delta T_f=T_f^0-T_f=(80.3-T_f)^0C[/tex] = Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte such as nitrobenzene)

[tex]K_f[/tex] = freezing point constant = [tex]7.45^0C/m[/tex]

m= molality  = 0.765

[tex](80.3-T_f)^0C=1\times 7.45\times 0.765[/tex]

[tex]T_f=74.6^0C[/tex]

Thus the freezing point of a 0.765 m solution of nitrobenzene in naphthalene is [tex]74.6^0C[/tex]

The freezing point of a 0.765 m solution of nitrobenzene in naphthalene is calculated using the freezing point depression constant (Kf) and the molality of the solution. The change in freezing point is found to be 5.69925° C, which is subtracted from the pure freezing point of naphthalene to obtain 74.6° C as the final freezing point of the solution.

To determine the freezing point of a solution, you can use the formula for the freezing point depression (ΔTf), which states that ΔTf = Kf * m, where Kf is the freezing point depression constant for the solvent and m is the molality of the solution. In this case, the given Kf for naphthalene is 7.45° C kg/mol, and the molality (m) of the nitrobenzene solution is 0.765 m (which means 0.765 moles of nitrobenzene per kilogram of naphthalene).

The change in freezing point can be calculated as:

ΔTf = Kf * m

ΔTf = 7.45° C kg/mol * 0.765 mol/kg

ΔTf = 5.69925° C

After calculating the change in freezing point, subtract this value from the pure freezing point of naphthalene (Pure freezing point = 80.3° C) to find the freezing point of the solution:

Freezing point of the solution = Pure freezing point - ΔTf
Freezing point of the solution = 80.3° C - 5.69925° C
Freezing point of the solution = 74.60075° C (rounded to 74.6° C)

Answer:

The answer is B, HNO3 solution of 0.000015 M yields a pH of 4.8.

Explanation:

The equation to find the pH of a solution is the following:

[tex]ph = - log( {h}^{ + } ) [/tex]

Since HNO3 is a strong acid, it almost 100% dissociates according to a 1:1 molar ratio, into hydrogen cations and nitrate anions, meaning the concentration of hydrogen ions is nearly the same as the concentration of the acid sollution.

[tex]ph = - log(0.000015) = 4.8239...[/tex]

We can round that up to 4.8, meaning we have our answer, 0.000015 M.

Ethan can defend his conclusion by stating that the change he observed, from a brown solid to a black powder, is a chemical change. He can refer to the definition of chemical properties and cite examples of other chemical changes to support his argument.

Ethan can defend his conclusion by stating that the change he observed, from a brown solid to a black powder, is a chemical change. Chemical changes involve the production of a different kind of matter from the original matter. In this case, the substance changed its color and composition when heated, indicating that a chemical reaction occurred.

Ethan can also refer to the definition of chemical properties, which are behaviors that are related to the change of one kind of matter into another kind of matter, further supporting his conclusion.

Furthermore, Ethan can cite examples of other chemical changes, such as rusting or food being cooked, digested, or rotting, to strengthen his argument that the observed change is a chemical change.

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Ethan can strengthen his conclusion about the chemical change by citing the color and state change, potential heat exchange, and could use Hess's Law to calculate the heat involved in this chemical change.

Ethan can defend his conclusion that the substance has undergone a chemical change by referring to the observed change in color and state from a brown solid to a black powder. This change in appearance is a strong indicator of a chemical change, as it suggests that a new kind of matter has been produced. Chemical changes are often accompanied by other types of observable changes such as the release or absorption of heat, which is an exothermic or endothermic process.

For example, a combustion reaction is an exothermic process that releases energy in the form of light and heat, like a burning oxyacetylene torch. On the other hand, an endothermic process absorbs heat, such as a cold pack used to treat muscle strains.

So, in his research, Ethan needs to further record if there's any heat exchange observed during this process. If there's a heat release or absorption, it gives more weight to his conclusion of this being a chemical change. Moreover, he could refer to Hess's Law to measure or calculate the heat involved in the chemical change for more concrete evidence.

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The average atomic mass of strontium is calculated by multiplying the mass of each isotope by its fractional abundance and summing these products. For strontium, this results in an average atomic mass of 87.712 amu.

To calculate the relative average atomic mass of strontium (Sr), we need to use the masses and percent abundances of its isotopes. The formula for this calculation is:

average atomic mass = (fractional abundance of isotope 1 × isotopic mass 1) + (fractional abundance of isotope 2 × isotopic mass 2) + ...

For strontium isotopes:

Adding these values together gives:

average atomic mass of Sr = 0.42 amu + 8.514 amu + 6.09 amu + 72.688 amu = 87.712 amu

Answer:

The atomic mass of lead is: 207.216 u

Explanation:

data                 Isotopes                     mass                      percent

                             1                      203.97302                      1.4

                             2                     205.974444                    24.1

                            3                      206.97587                       22.1

                            4                      207.97663                       52.4

atomic mass = (203.97302x 0.014) + (205.974444 x 0.241) +

                        (206.97587 x 0.221) + (207.97663 x 0.524)

atomic mass = 2.856 +49.639 + 45.742 + 108.979

atomic mass = 207.216 u

The atomic mass of the lead (Pb) would be 207.2168 atomic mass units.

It is the sum of the mass of all the protons as well as the neutrons that are present inside the nucleus.

As given in the problem element lead (Pb) consists of four naturally occurring isotopes with masses of 203.97302, 205.97444, 206.97587, and 207.97663 atomic mass units. The relative abundances of these four isotopes are 1.4, 24.1, 22.1, and 52.4%,

The atomic mass of the lead = .014×203.97302 + 0.241×205.97444  +0.221× 206.97587+ 0.524×207.97663

                                              =207.2168 atomic mass unit

Thus the atomic mass of the lead (Pb) would be 207.2168 atomic mass units.

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Answer:

dG will be the same -20 kcal/mol

Explanation:

The dG can be expressed in terms of the G(products) - G(reactants). If the amount of enzyme is doubled the Gibbs energy of the reactants and products will be the same, so the substraction dG has the same value

Answer:

Abundance of Ga 70.925 is 0.399 and percentage abundance of Ga 39.9%

Abundance of Ga 68.926 is 0.601 and percentage abundance is 60.1 %.

Explanation:

we know there are two naturally occurring isotopes of gallium Ga 68.926 and Ga 70.925.

First of all we will set the fraction for both isotopes

X for the isotopes having mass 70.925

1-x for isotopes having mass 68.926

The average atomic mass of Ga is 69.72.

we will use the following equation,

70.925 x + 68.926 (1-x) = 69.72

70.925 x + 68.926 - 68.926x = 69.72

70.925x- 68.926x = 69.72 - 68.926

1.99 x = 0.794

x= 0.794/ 1.99

x= 0.399

abundance of Ga 70.925 is 0.399, because we solve the fraction x.

0.399 × 100 = 39.9 %

39.9 % is percentage abundance of Ga 70.925

now we will calculate the abundance of Ga 68.926.

(1-x)

1 - 0.399 = 0.601

abundance of Ga 68.926 is 0.601 and percentage abundance is

0.601 × 100= 60.1 %

Answer:

The answer to your question is letter B, 2-methylhexane.

Explanation:

Remember that for naming organic compounds first, we need to look for the largest chain of carbons.

In your example, the largest chain is horizontal and has 6 carbons.

Later, we need to circle all the branches, in your example there is only one branch located close to the left side

After that, we number the carbons of the main chain, starting in the corner with more branches, in your example we start from the first carbon on the left.

Finally, start naming the number of the carbon branch, later hte name of the branch and finally the name of the main chain.

Answer: [tex]N_2[/tex]

Explanation:

Element is a pure substance which is composed of atoms of similar elements.

It can not be decomposed into simpler constituents using chemical reactions.Example: Nitrogen [tex](N_2)[/tex]

Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.

It can be decomposed into simpler constituents using chemical reactions. Example: carbon dioxide [tex](CO_2)[/tex] , water [tex](H_2O)[/tex], carbon monoxide [tex](CO)[/tex]

The chemical symbol which represents an element is N₂

An Element is defined as a pure substance which is composed of atoms of similar elements. It can not be further decomposed into simpler constituents by using chemical reactions. for Example: Nitrogen gas , N₂

On the other hand, a Compound is a pure substance which is made from the  atoms of different elements which are combined together in a fixed ratio by mass. They can be decomposed into simpler constituents by using chemical reactions. for example: carbon dioxide  , water , carbon monoxide etc.

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Answer:

A

Explanation:

Each 12 oz of latte contains 8 oz of milk, as the group of people ordered 12 lattles we need

12 x 8 = 96 oz of milk

As 33.8 oz is a litre

33.8 oz - 1 L

96 oz - x

x = [tex]\frac{96}{33.8}[/tex] = 2.84 L

As Brandon have 2.5 L of milk

2.84 L - 2.5 L = 0.34 L

He will be short 0.34 L

He will need 2.84 L, so he is short 0.34 L. Option A

Each latte contains 8 oz of milk, and you have 12 lattes.

Total milk needed = 8 oz/latte * 12 lattes = 96 oz

We convert ounces to liters using the conversion factor provided (1 L = 33.8 oz):

Total milk needed = 96 oz / 33.8 oz/L = 2.84 L

Then;

He has 2.5 liters of milk left.

Comparing what he needs to what he has:

He needs 2.84 liters

He has  2.5 liters

Looking at what we have done we can see that he will need 2.84 L, so he is short 0.34 L.

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Answer:

c. reducing oxygen level on hemoglobin.

Explanation:

Carbon monoxide, whose chemical formula is CO, is an odorless, colorless, flammable and highly toxic gas. It can cause death when breathing at difficult levels. It occurs when combustible materials such as gas, gasoline, kerosene, coal, oil, tobacco or wood are burned in low oxygen environments. Fireplaces, boilers, water heaters and household appliances that burn fuel, such as stoves, can also produce it if they are not working properly. Vehicles stopped with the engine running also fire him.

Carbon monoxide modifies the amount of oxygen available to cells, which hinders cellular function.

Carbon monoxide binds tightly to hemoglobin preventing the red blood cell from carrying adequate oxygen, leading to hypoxic injury. Other chemicals such as carbon tetrachloride promote free radicals, which injure cells and destroy cellular membranes.

Answer:

b

Explanation:

Answer:

The answer to your question is: 5 neutrons

Explanation:

Beryllium has 4 protons

# of neutrons in beryllium-9

Atomic number (Z) = 4 (number of protons)

Mass  number (A) = 9 (number of protons + neutrons)

                          Mass number = number of protons + number of neutrons

                          9   = 4 + number of neutrons

                          neutrons = 9 - 4

                          neutrons = 5

Beryllium has 4 protons in its nucleus, so the atomic number is 4. Beryllium-9 mass number will be 9 which is equal to neutrons added to protons. So, the correct answer is 5.

Atomic number is defined as the charged number of an atomic nucleus. It is equal to number of protons present in the nucleus. The number of protons define the identity of an element , for example if an element has 5 protons it is Boron (B), no matter how many neutrons are present in it.

In the periodic table, Atomic number is written at the upper left corner which is equal to the number of protons.

The atomic number is indicated as a left subscript representing a particular atomic species in the symbol. An atom or a nucleus pf Carbon (Chemical symbol C), it may be written as [tex]_6C[/tex].

Atomic number is important as we can easily identity the element of an atom and periodic table is arranged according to increased atomic number.

Thus, Beryllium has 4 protons in its nucleus, so the atomic number is 4. Beryllium-9 mass number will be 9 which is equal to neutrons added to protons. So, the correct answer is 5.

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Answer:

orbital

Explanation:

electrons are found in an orbital

Answer:

The weaker interaction in between acetone and chloroform.

Explanation:

The interactions among acetone and acetone or chloroform with chloroform are stronger because both substances are non polar, they are attracted by the interactions called dipole - dipole. This kind of joints use some hydrogen bridge to join the two compounds.

In the case of the interaction acetone  chloroform, they are similar but not the same substance, the acetone is less polar than the chloroform, so is necessary to induce a dipole, and this joint is less strong than the normal dipole - dipole.  

Chloroform-acetone interactions are stronger than acetone-acetone and chloroform-chloroform interactions.

The relative strength of chloroform-acetone interactions compared to acetone-acetone and chloroform-chloroform interactions depends on the polarities of the molecules involved. Chloroform, CHCl3, is more polar than acetone, CH3COCH3. The presence of the more polar chloroform molecule leads to stronger dipole-dipole interactions with acetone compared to the acetone-acetone and chloroform-chloroform interactions, making the chloroform-acetone interactions stronger than the other two.

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Answer:

0.09 moles of Br₂

Explanation:

Bromine liquid it refers at Br₂ molecule which is liquid at room temperature.

Now to calculate the number of moles we use the following formula:

number of moles = mass (g) / molecular mass (g/mol)

For Br₂ molecule we have:

number of moles = 14.4 / 160 = 0.09 moles of Br₂

Answer:

The number of moles of bromine liquid produced is 0.09.

Explanation:

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

Mass of bromine liquid = 14.4 g

Molecular mass of bromine liquid [tex]Br_2[/tex]= 160 g/mol

Moles of bromine liquid = [tex]\frac{14.4 g}{160 g/mol}=0.09 mol[/tex]

The number of moles of bromine liquid produced is 0.09.

Answer:

higher, left

Explanation:

Given that the reaction consumes 462 kJ of energy. It means that the reaction is a endothermic reaction.

In the energy profile of the endothermic diagrams, The reactants are at a very low level as compared to the products and hence, energy is supplied to overcome this difference.

Hence, The energy levels of products are higher than the energy level of reactant.

Hence, already stated, heat is required by the reaction and thus heat is written to the reactant side which is to the left side of the equation.