Write the balanced equation for each of the following changes and identify whether heat is a product or needed to start the reaction (do not include 'heat' in your balanced equation, simply identify whether it is a product or reactant):
(a) the sublimation of dry ice [conversion of CO2(s) directly to CO2(g)] Heat is a product and is given off by the reaction. Heat is a reactant and is needed to start the reaction.
(b) the reaction of 1 mol of sulfur dioxide with oxygen. Heat is a reactant and is needed to start the reaction. Heat is a product and is given off by the reaction.

Answer:

C.) protons and neutrons

Explanation:

Most atoms contain proton(s), neutron(s), and electron(s). Within the nucleus of an atom, there are protons and neutrons. Electrons are located outside of the nucleus.

Answer:

A.) If the temperature increases, then crickets will chirp more.

Explanation:

The hypothesis is a testable statement that can be supported or disproved through experimentation.

A.) is correct. This statement clearly identifies what will (supposedly) happen when a variable is manipulated. Once an experiment is carried out, this hypothesis can be supported or negated.

B.) is incorrect. This is an opinion, not an objective statement. This statement is subjective and cannot be backed by evidence.

C.) is incorrect. Hypotheses are not questions. This statement also does not state how temperature could affect a cricket's chirp. However, questions can often lead to the formation of a hypothesis.

D.) is incorrect. The first part of the statement is an observation, and the second part is an assumption. Like in answer C, this information can be used as the basis in making a hypothesis.

Answer:

72.521%

Explanation:

The mass percent of barium in barium cyanide is 72.1%

Mass per cent is a way of expressing a concentration or describing the component in a particular mixture.

The solution composition can be described in mass percentage which shows the mass of solute present in a given mass of solution

The Mass percent formula is expressed as solving for the molar mass also for the mass of every element in 1 mole of the compound.

Given,

Molecular mass of Ba(CN)₂ = 190

Atomic mass of Ba = 137

mass percent = (mass of Ba ÷ molecular mass of compound) × 100

                    = (137 ÷ 190) × 100

                     = 72.1 %

Therefore,  the mass percent of barium in barium cyanide is 72.1%

Learn more about Mass percent, here:

https://brainly.com/question/5394922

#SPJ2

Answer:

E = 5.69x10⁻²⁸m

Explanation:

To solve this question we neeed to convert the wavelength in meters to energy in joules using the equation:

E = hc / λ

Where E is energy in joules, h is Planck's constant = 6.626x10⁻³⁴Js

c is light constant = 3.0x10⁸m/s

And λ is wavelength in meters = 349m

Replacing:

E = 6.626x10⁻³⁴Js*3.0x10⁸m/s / 349m

E = 5.69x10⁻²⁸m

The energy of the wavelength at which the local AM radio station is broadcasting is: A. \(5.69 \times 10^{-19}\;J\)

Given the following data:

Scientific data:

To calculate the energy of the wavelength at which the local AM radio station is broadcasting, we would apply Einstein's equation for photon energy:

Mathematically, Einstein's equation for photon energy is given by the formula:

\(E=\frac{hv}{\lambda}\)

Where:

Substituting the given parameters into the formula, we have;

\(E=\frac{6.626 \times 10^{-34}\times 3 \times 10^8}{3.49 \times 10^{-7}}\\\\E=\frac{1.99 \times 10^{-25}}{3.49 \times 10^{-7}} \\\\E=5.69 \times 10^{-19}\;Joules\)

Read more on wavelength here: https://brainly.com/question/14593563

Answer:

When HCl (hydrochloric acid) and KOH (potassium hydroxide) are neutralized, they react to form water (H2O) and a salt (KCl). The balanced equation is:

HCl + KOH → KCl + H2O

In this reaction, one mole of HCl reacts with one mole of KOH to form one mole of water and one mole of KCl.

During titration of HCl with KOH, the point at which the reaction is complete is called the equivalence point. At the equivalence point, the moles of H+ ions and OH- ions are equal in the titration mixture.

Since one mole of HCl reacts with one mole of KOH, and H+ ions are present in HCl and OH- ions are present in KOH, the number of moles of H+ ions will be equal to the number of moles of OH- ions at the equivalence point.

Therefore, at the equivalence point, the number of moles of H+ ions will be equal to the number of moles of OH- ions in the titration mixture when HCl is exactly neutralized by KOH.

When the HCl is neutralized by KOH, the equivalence point is reached. During titration, the amount of HCl is determined using a basic solution of known concentration.

It is possible to calculate the amount of KOH required for complete neutralization if the initial concentration of the HCl solution is known. The balanced chemical equation for the reaction between HCl and KOH is:HCl + KOH → KCl + H2OThe stoichiometry of the reaction indicates that one mole of HCl reacts with one mole of KOH to produce one mole of H2O. Thus, the number of moles of H+ ions is equal to the number of moles of OH- ions when the equivalence point is reached.In an acid-base reaction, the number of moles of hydrogen ions (H+) produced by the acid is equal to the number of moles of hydroxide ions (OH-) produced by the base. When the HCl is exactly neutralized by the KOH, the number of moles of H+ ions is equal to the number of moles of OH- ions in the titration mixture.

This is due to the balanced chemical equation for the reaction, which shows that one mole of HCl reacts with one mole of KOH to produce one mole of water (H2O).Thus, at the equivalence point, the number of moles of H+ ions is equal to the number of moles of OH- ions. This is the point at which all of the HCl has reacted with the KOH. After the equivalence point, the excess KOH will react with the H2O to produce OH- ions, resulting in a basic solution.

for such more questions on solution

https://brainly.com/question/25326161

#SPJ8

The concentration of the solution in molarity, given that 6.802×10²⁰ particles were dissolved in 0.38 L of water is 3.0×10⁻³ M (option B)

First, we shall determine the number of mole that contains 6.802×10²⁰ particles of Mn(NO₃)₃. Details below:

From Avogadro's hypothesis,

6.022×10²³ particles = 1 mole of Mn(NO₃)₃

Therefore, we can say that

6.802×10²⁰ particles = 6.802×10²⁰ / 6.022×10²³

6.802×10²⁰ particles = 0.001 mole of Mn(NO₃)₃

Finally, we shall obtain the molarity of the solution. Details below:

Molarity of solution = mole / volume

Molarity of solution = 0.001 / 0.38

Molarity of solution = 3.0×10⁻³ M (option B)

Learn more about molarity:

https://brainly.com/question/16073358

#SPJ1

Answer: KE = 8.6917248 J

I'm not for sure but I am pretty positive this is the answer

Answer:

Velocity

Explanation:

it is the rate of displacement over time in a SPECIFIED DIRECTION i.e it has both magnitude and direction

\(p = 10 \frac{a - b}{(c + t)} \)

Vapor Pressure of Water calculator Formula:

\(p = 10 \frac{a - b}{(c + t)} \)

The molar mass we calculated, 17.92 g/mol, is much lower than the molar mass of CO2, so it is unlikely that the gas is CO2.

Rate of effusion is the measure of the speed at which a gas escapes through a tiny opening, such as a small hole or a porous barrier, into a vacuum or another region of lower pressure. The rate of effusion is determined by the average speed of the gas particles and the size of the opening through which they pass. The rate of effusion of a gas is inversely related to the square root of its molar mass, according to Graham's law of effusion.

The square root of a gas's molar mass has an inverse relationship with the rate of effusion of that gas. The rate of effusion is expressed as follows:

rate1/rate2 = sqrt(MM2/MM1)

where rate1 and rate2 are the rates of effusion of the two gases and MM1 and MM2 are their molar masses.

Using the given data, we can write:

rate1/rate2 = sqrt(MM2/MM1)

1/15 = sqrt(MM2/MMglucose)

1/12 = sqrt(MM2/MMN2)

Dividing these two equations, we get:

1/15 ÷ 1/12 = sqrt((MM2/MMglucose)/(MM2/MMN2))

4/5 = sqrt(MMglucose/MMN2)

Squaring both sides, we get:

16/25 = MMglucose/MMN2

MMglucose = (16/25) x 28 = 17.92 g/mol

The molar mass of glucose is 180 g/mol. The gas evolved from the fermentation of glucose is mainly carbon dioxide (CO2), so the molar mass of the gas is close to the molar mass of CO2, which is 44 g/mol. The molar mass we calculated, 17.92 g/mol, is much lower than the molar mass of CO2, so it is unlikely that the gas is CO2.

A possible gas that could be produced from the fermentation of glucose is methane (CH4). The molar mass of methane is 16 g/mol, which is closer to the molar mass we calculated. Therefore, the gas evolved from the fermentation of glucose could be methane.

To know more about Graham's law of effusion, visit:

https://brainly.com/question/22359712

#SPJ1

Answer:

B. po

Explanation:

sana po makatulong

Answer:

The Bohr model show the protons in a carbon atom using the model;  "Electrons move in fixed orbits around a nucleus of protons and neutrons."

According to Bohr's model of the atoms, the Rutherford model is basically correct. This implies that Bohr model accepts the idea of a nucleus containing nucleons(protons and neutrons).

In addition, the model also postulates that electrons are found in fixed orbits. These fixed orbits are called energy levels or shells.

A graphic description of this is shown in the image attached to this answer.

Learn more: brainly.com/question/3964366

Explanation:

Because there are two mutually connected nuclei in aromatic ring of phenacetin that are not related to other protons and whose shift differences are equal to coupling constant, ring displays AB pattern.

The ring protons in benzene experience deshielding because their chemical shift is 7.3 parts per million (ppm) as opposed to 5.6 for the vinylic proton in cyclohexene, and because the induced magnetic field outside the ring has the same direction as the external field.

Around 6–8 ppm of benzene contains protons. Due to the deshielding action of the aromatic ring, this is higher than the protons in other hydrocarbons like alkanes and alkenes.

To learn more about NMR spectrum visit:

brainly.com/question/29775399

#SPJ4

Answer:Due to the presence of two mutually connected nuclei and a shift difference equal to the coupling constant, the aromatic ring of phenacetin exhibits the AB pattern.

Explanation:

The Statement 3 (the products have more potential energy than the reactants in an exothermic reaction) is partially correct because the products do have lower potential energy than the reactants in an exothermic reaction.

The correct statement regarding endothermic and exothermic reactions is:

Energy is absorbed in an endothermic reaction.

In an endothermic reaction, energy is taken in from the surroundings, usually in the form of heat. The reactants have a lower energy level than the products, so energy must be absorbed to reach the higher energy state of the products. This energy absorption causes a decrease in the temperature of the surroundings, making the reaction feel cold.

On the other hand, in an exothermic reaction, energy is released. The reactants have a higher energy level than the products, so energy is released during the reaction, usually in the form of heat. This energy release causes an increase in the temperature of the surroundings, making the reaction feel warm or hot.

Therefore, statement 2 (energy is released in an endothermic reaction) and statement 4 (the products have more potential energy than the reactant in an endothermic reaction) are incorrect.

For more such questions on energy

https://brainly.com/question/5650115

#SPJ8

Answer: 8 valence electrons

Explanation:

Answer:

plastic

........................

Answer:

No, We cannot change a gravitational field directly. Gravity is due or caused by the energy in objects with mass. ... Either way, once a particle, it is an object thus a source of gravitational potential.

Hope it helps,

Please mark me as the brainliest

Thank you

there are no current practical outer space applications of artificial gravity for humans due to concerns about the size and cost of a spacecraft necessary to produce a useful centripetal force comparable to the gravitational field strength on Earth.

Answer:

Explanation:Because of the delocalised electrons exposed above and below the plane of the rest of the molecule, benzene is obviously going to be highly attractive to electrophiles - species which seek after electron rich areas in other molecules.

Answer:

Benzene has a pi electron system that is electron rich.

Electrophiles are molecules that are attracted to electron rich molecules as they are electron deficient in order to form a more stable complex.

Hence, as benzene is electron rich, electrophiles will be attracted to it.

Answer: is the benefit worth the cost?

Explanation: for those on edge :)

Answer:

Is The Benefit Worth The Cost?

Explanation:

Explanation:

To calculate the heat gained by nickel, we can use the formula:

q = m * c * ΔT

where q is the heat gained, m is the mass of the nickel, c is the specific heat of nickel, and ΔT is the change in temperature.

Given:

- Mass of nickel, m = 31.4 g

- Specific heat of nickel, c = 0.443 J/g · °C

- Change in temperature, ΔT = 64.2 °C - 27.2 °C = 37.0 °C

Substituting the values into the formula, we get:

q = (31.4 g) * (0.443 J/g · °C) * (37.0 °C)

Simplifying the calculation, we get:

q = 584 J

Therefore, the heat gained by nickel when 31.4 g of nickel is warmed from 27.2 °C to 64.2 °C is 584 J.

Answer: K is bigger in atomic size. The metallic character increases as the size increases.

Explanation:

Reactivity of a metal is defined as the tendency of an element to lose electrons. The metallic character increases as we move down a group and it decreases as we move across a period.

When the size of an element increases, the valence electrons gets away from the nucleus and the tendency of an element to loose electrons increases.

In a group, the size of an element increases because there is an addition of new shell and electron is added in that shell.

Thus for alkali metals, the metallic character increases from Lithium to sodium to potassium and so on.

The concentration of the solution reduces and the number of moles of solute isn't affected.

Data;

1. When the solution is diluted, the concentration changes and this time, the concentration reduces.

Using dilution formula

\(c_1 v_1 = c_2 v_2\\12 * 50 = c_2 * 200\\c_2 = \frac{600}{200} \\c_2 = 3M\)

The concentration of the solution reduces.

2. The number of moles remains the same.

When a solution is diluted, the number of moles remains the same because there's no change in the mass of the solute.

Learn more on concentration of a solution here;

https://brainly.com/question/2201903

Atom 1,2,6 and 7 are coplanar with the two carbons in the double bond.

In the structure below, the two carbons in the double bond are labeled as 1 and 2. To determine which of the labeled atoms are coplanar with the two carbons in the double bond, it is necessary to examine the arrangement of the atoms in space.

The atoms that are coplanar with the two carbons in the double bond are likely to be the atoms bonded directly to the double-bonded carbons, such as atoms 3, 4, 5, and 6 in the structure. These atoms are all located in the same plane as the double-bonded carbons, as indicated by their shared electrons in the covalent bonds. Atom 7, on the other hand, is not coplanar with the double-bonded carbons because it is not directly bonded to either carbon.

It is worth noting that molecular structures can be represented in different ways, and the 2D representation in the structure above may not accurately depict the true 3D arrangement of the atoms. Nevertheless, the principle of determining coplanarity based on bonding relationships remains the same.

Learn more about carbons:

brainly.com/question/22530423

#SPJ4

Answer:

\(m_{H_2}=12.6gH_2\)

Explanation:

Hello there!

In this case, given the reaction:

\(3 H_2+ N_2 \rightarrow 2NH_3\)

It is possible to compute the necessary grams of hydrogen which produce 71.1 g of ammonia, given the 3:2 mole ratio and their molar mass as shown below:

\(m_{H_2}=71.1gNH_3*\frac{1molNH_3}{17.04gNH_3}*\frac{3molH_2}{2molNH_3} *\frac{2.02gH_2}{1molH_2}\\\\m_{H_2}=12.6gH_2\)

Best regards!

Charles's law of gases states that the density of an ideal gas is inversely proportional to its temperature at constant pressure.

The equation is as follows;

Va/Ta = Vb/Tb

Where;

0.67/362 = 1.12/Tb

0.00185Tb = 1.12

Tb = 605.41K

This temperature in °C is 605.41 - 273 = 332°C

Learn more about Charles's law at: https://brainly.com/question/16927784

#SPJ1

Answer:

157.2 mL

Explanation:

The following data were obtained from the question:

Density (D) of liquid = 0.878 g/mL

Mass (m) of liquid = 138 g

Volume (V) of liquid =.?

Density of a substance is simply defined as the mass of the substance per unit volume of the substance. Mathematically, it is expressed as:

Density (D) = mass /volume

D = m/V

With the above formula, we can obtain the volume of the liquid as follow:

Density (D) of liquid = 0.878 g/mL

Mass (m) of liquid = 138 g

Volume (V) of liquid =.?

D = m/V

0.878 = 138/V

Cross multiply

0.878 × V = 138

Divide both side by 0.878

V = 138/0.878

V = 157.2 mL

Therefore, 157.2 mL of the liquid must be provided.

Answer:

0.273 mol H₂O

General Formulas and Concepts:

Chemistry - Atomic Structure

Explanation:

Step 1: Define

4.92 g H₂O

Step 2: Identify Conversions

Molar Mass of H - 1.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol

Step 3: Convert

\(4.92 \ g \ H_2O(\frac{1 \ mol \ H_2O}{18.02 \ g \ H_2O} )\) = 0.27303 mol H₂O

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

0.27303 mol H₂O ≈ 0.273 mol H₂O

Answer:

Covalent bond or common bond is one of the types of chemical bonds. This connection arises from electronic participation. In fact, atoms that need to receive electrons to achieve stable electron arrangement (noble gas electron arrangement or octagonal arrangement) share electrons in their valence layer with other atoms. In this case, the transfer of electrons from one atom to another does not take place, but only a pair of electrons, called a bonded or shared electron pair, belongs to the nucleus of two atoms.

Exothermic refers to chemical interactions that aerobic respiration. Combustion reactions release higher energy. Endothermic refers to atoms and molecules that either use or absorb reactive power.

A chemical process known as an endothermic releases energy as heat or light. It is an endothermic reaction's opposite. Chemical equation expressed as reactants + products + energy. An reaction mechanism is one in which electricity is given off as light or warmth.

A response is deemed to be exothermic if it produces heat while also undergoing a net decrease in basic enthalpy change. Samples include those type of combustion, iron rust, including water froze. Exothermic processes are those that discharge heat and energy into the surroundings.

To know more about exothermic visit:

https://brainly.com/question/13243759

#SPJ1