Explain why a buffer can be prepared from a mixture of NH4CL and NaOH but not from NH3 and NaOH .​

Answer:

Chemical change

Explanation: Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.

Answer:

It's A: Weak & Vulnerable

Answer:

Ernest Rutherford found that the atom is mostly empty space, with nearly all of its mass concentrated in a tiny central nucleus. The nucleus is positively charged and surrounded at a great distance by the negatively charged electrons.

Explanation:

Rutherford's atomic model became known as the nuclear model. In the nuclear atom, the protons and neutrons, which comprise nearly all of the mass of the atom, are located in the nucleus at the center of the atom.

Answer:

B. It undergoes a physical change.

Explanation:

Hello there!

In this case, since we know that chemical changes lead to the formation of new atoms and/or compounds due to the bonds rearrangement of the initial substances and the physical changes occur without changing the composition of the initial substances, we can infer that, since melting is a process that changes the phase of matter from solid to liquid without changing the identity of the initial substance, the answer to this question would be B. It undergoes a physical change. because the other options describe chemical changes.

Best regards!

Answer:

B. It undergoes a physical change.

Explanation:

At room temperature, the iron atoms are in an unusual loosely packed open arrangement; as iron is heated past 912 degrees Celsius, the atoms become more closely packed before loosening again at 1,394 degrees Celsius and ultimately melting at 1,538 degrees Celsius.

Answer:

A physical property is a characteristic of matter that is not associated with a change in its chemical composition. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity.

Explanation:

Conductivity is an example of a physical property. Physical properties are characteristics of a substance that can be observed or measured without changing the substance's chemical composition.

Conductivity specifically refers to a material's ability to conduct electricity or heat. Materials with high electrical conductivity allow electricity to flow easily through them, while materials with high thermal conductivity conduct heat efficiently.

Examples of conductive materials include metals like copper and aluminium, which are widely used in electrical wiring and heat transfer applications due to their excellent conductivity properties.

Learn more about Conductivity, here:

https://brainly.com/question/33823148

#SPJ6

Answer:

Given the reaction:

Fe+H

2

O→Fe

3

O

4

+H

2

If the number of electrons lost or gained during the changes is x. Then, the value of x is 8.

The balanced chemical equation is as follows:

3Fe+4H

2

O→Fe

3

O

4

+4H

2

The oxidation number of hydrogen changes from +1 (in water) to 0 (in hydrogen molecule).

Thus, net change in the oxidation number of hydrogen per atom is 1.

There are 8 H atoms.

Hence, the total change in the oxidation number of 8 hydrogen atoms is 8.

Hence, 8 electrons are involved in the redox reaction.

Hence, x=8.

Answer:

im absoulutely positive it is C

The society with the least negative effects on the environment is probably the one with a small population, traditional farming methods, no access to contemporary technology, and self-sufficient food production.

This is due to the fact that their way of living is less dependent on modern infrastructure and technology, both of which have a negative impact on the environment. Additionally, their agricultural methods are probably more environmentally friendly and sustainable.

The environmental effects of the other societies on the list would all be greater. Because of the use of fossil fuels and the production of products that require a lot of resources, a big, industrialized society with high levels of consumption would have a significant carbon footprint.

It would still take a lot of resources to maintain its infrastructure and create products in a less populous, highly industrialized society with moderate consumption levels, which would have a negative effect on the environment.

Given that the size of the population alone would necessitate significant resource consumption and infrastructure development, a big population with moderate industrialization and consumption levels would also have a big effect on the environment.

learn more about the population here

https://brainly.com/question/29885712

#SPJ1

Answer:

Its D

Explanation:

Answer:C

Explanation:

Answer:

A hypothesis is a testable statement that is proposed to explain an observation/theory. In this case, one hypothesis that could be used is: Taller people have longer arms than smaller people. You could also say: As the height of an individual increases, the length of their arms also increases.

Independent variables are the variable that is manipulated. In this case, the independent variable is the height of the individual.

Dependent variables are those that change in response to the independent variable. In this case, the dependent variable is arm length.

Group 8 elements are also known as the noble gasses. These elements already have a full valence shell with 8 valence electrons. This leaves the elements non-reactive as they are already stable and in a low energy state.

The false statement regarding polar molecules is option B: "Their electrons are evenly distributed."

Polar molecules are characterized by an uneven distribution of electron density within the molecule. This means that the electrons are not evenly distributed, resulting in a partial positive charge in one part of the molecule and a partial negative charge in another part. This uneven distribution occurs due to differences in electronegativity .

Options A, C, and D are true statements. Option A states that they are asymmetric, meaning their shape is not symmetrical. Option C states that polar molecules can attract other polar molecules. Option D states that polar molecules generally have a high specific heat, which means they require a significant amount of energy to change their temperature.

learn more about polar molecules :

https://brainly.com/question/4494385

Answer:

The ratio of the mass of an adult rhino to the mass of a small egret is

(1400 kg)/(0.76 kg) = 1842.11

The ratio of the mass of a proton to the mass of an electron is

1836.15

The two ratios are very similar, the ratio of the masses of the proton to the electron being slightly smaller.

Ammonia chemical formula : NH3

Ammonia molar mass : 14 + (1×3) = 17

Mass = Mol × mm

= 3.5mol × 17 = 59.5g

See pic for formula

nvm i think your question is incomplete. pls report my answer i thought u are asking the mass of ammonia

Answer:

0.00916432 km/s

21648 inches/minute

Explanation:

1 kilometre / second =

2236.936 miles per hour

20.5/2236.9=0.00916432km/s

1 mile per hour =

1056 inches / minute

20.5×1056=21648 inches/minute

The pH of the solution made by dissolving 135 g of sulphuryl chloride in water to make 1 dm^3 of solution will be acidic.

To calculate the pH of the solution made by dissolving 135 g of sulphuryl chloride (SOCl2) in water to make 1 dm^3 of solution, we need to consider the hydrolysis reaction of sulphuryl chloride with water:

SOCl2 + 2H2O → H2SO4 + 2HCl

In this reaction, sulphuryl chloride reacts with water to form sulphuric acid (H2SO4) and hydrochloric acid (HCl).

First, we need to determine the number of moles of sulphuryl chloride in the solution. To do this, we divide the given mass of sulphuryl chloride by its molar mass:

Molar mass of SOCl2 = 32.5 g/mol + 2 × 35.5 g/mol = 118.5 g/mol

Number of moles of SOCl2 = Mass / Molar mass = 135 g / 118.5 g/mol = 1.14 mol

Since we are dissolving 1.14 mol of sulphuryl chloride in 1 dm^3 of solution, the concentration of sulphuryl chloride is 1.14 M.

Now, we can consider the hydrolysis reaction. The hydrolysis of sulphuryl chloride produces hydrochloric acid, which is a strong acid. When a strong acid is completely dissociated in water, it results in a solution with a low pH. Therefore, the pH of the solution will be acidic.

For more such questions on pH visit:

https://brainly.com/question/12609985

#SPJ8

Answer:

It has reaced thermal equlibrum

The partial charges on each fluorine atom are negative. Option B) The central O atom is the correct answer. Option B

The partial charges in a molecule are determined by the electronegativity values of the atoms involved. Electronegativity is the ability of an atom to attract electrons towards itself in a chemical bond. In the case of \(F_2O\), fluorine (F) is more electronegative than oxygen.

Fluorine is the most electronegative element on the periodic table, meaning it has a high ability to attract electrons. Oxygen is also relatively electronegative but less so than fluorine. When fluorine atoms bond with oxygen, the shared electrons will be pulled more towards the fluorine atoms, creating a polar covalent bond.

In \(F_2O\), each fluorine atom will pull the shared electrons towards itself, resulting in a higher electron density around the fluorine atoms. This creates a region of partial negative charge around the fluorine atoms.

Conversely, the oxygen atom will have a region of lower electron density and, therefore, a partial positive charge. This is because the shared electrons spend more time around the fluorine atoms due to their higher electronegativity.

Option B

For more such question on partial charges visit:

https://brainly.com/question/29974793

#SPJ8

Answer:

68.1% is percent yield of the reaction

Explanation:

The reaction of methane with oxygen is:

CH₄ + 2O₂ → CO₂ + 2H₂O

Where 2 moles of oxygen react per mole of CH₄

Percent yield is:

Actual yield (28.2g CO₂) / Theoretical yield * 100

To solve this question we need to find theoretical yield finding limiting reactant :

Moles CH₄:

15.1g CH₄ * (1mol / 16.04g) = 0.9414 moles

Moles O₂:

81.2g * (1mol / 32g) = 2.54 moles

For a complete reaction of 0.9414 moles of CH₄ are needed:

0.9414 moles CH₄ * (2 mol O₂ / 1mol CH₄) = 1.88 moles of O₂. As there are 2.54 moles, O₂ is in excess and CH₄ is limiting reactant

In theoretical yield, the moles of methane added = Moles of CO₂ produced. That is 0.9414 moles CO₂. In grams = Theoretical yield:

0.9414 moles CO₂ * (44.01g / mol) = 41.43g CO₂

Percent yield: 28.2g CO₂ / 41.43g CO₂ * 100=

Answer:

Explanation:

10L

Taking into accoun the ideal gas law, The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.

An ideal gas is a theoretical gas that is considered to be composed of point particles that move randomly and do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:  

P×V = n×R×T

where P is the gas pressure, V is the volume that occupies, T is its temperature, R is the ideal gas constant, and n is the number of moles of the gas. The universal constant of ideal gases R has the same value for all gaseous substances.

In this case, you know:

Replacing in the ideal gas law:

0.884 atm×V= 0.857 moles× 0.082\(\frac{atmL}{molK}\) ×328 K

Solving:

\(V=\frac{0.857 molesx 0.082 \frac{atmL}{molK}x328 K}{0.884 atm}\)

V= 26.07 L

The volume of a container that contains 24.0 grams of N2 gas at 328K and 0.884 atm is 26.07 L.

Learn more:

Answer:

The temperature of the iron block is 68.5°C.

Explanation:

The heat released during condensation of water is used to warm the iron block:

q = m_H2O * ΔH_vap = m_fe * c_fe * ΔT

where q is the heat released, m_H2O is the mass of water condensed, ΔH_vap is the enthalpy of vaporization for water, m_fe is the mass of iron, c_fe is the specific heat capacity of iron, and ΔT is the change in temperature of the iron block.

Rearranging the equation gives:

ΔT = (m_H2O * ΔH_vap) / (m_fe * c_fe)

Substituting the given values gives:

ΔT = (0.95 g * 44.0 kJ/mol) / (75.0 g * 0.449 J/(g°C))

ΔT = 46.5°C

Therefore, the final temperature of the iron block is:

T_f = T_i + ΔT = 22°C + 46.5°C = 68.5°C.

The final temperature of the iron block is 68.5°C.

An indicator usually signals the endpoint of a neutralization reaction by undergoing a color change. They aid in discovering the point of equivalence of a titration.

The kind of indicator used depends on the nature of acid/base reacted.

In the case of  CH3NH2 with HBr which  strong acid and weak base titration, suitable indicators include; bromophenol blue, methyl  orange, methyl red, and chlorophenol blue.

In the case of HNO3 with NaOH, this is a strong acid, strong base titration hence phenolphthalein, methyl red, chlorophenol, and bromothymol blue cresol red blue are suitable indicators.

In the case of  HNO2 with KOH, this a weak acid, strong base titration and the suitable indicators are cresol red and  phenolphthalein.  

For more information on titration see

https://brainly.com/question/22536636

The growth of the new plant depicts the asexual reproduction characteristic. The characteristic that describes the growth of the new plant in Stephan's mother cutting a twig from a rose bush and planting it in the soil is asexual reproduction.

Asexual reproduction is the mode of reproduction by which organisms generate offspring that are identical to the parent's without the fusion of gametes. Asexual reproduction is a type of reproduction in which the offspring is produced from a single parent.

The offspring created are clones of the parent plant, meaning they are identical to the parent.The new plant in Stephan’s mother cutting a twig from a rose bush and planting it in the soil depicts the process of asexual reproduction, which is the ability of a plant to reproduce without seeds. In asexual reproduction, plants can reproduce vegetatively by cloning themselves using their roots, bulbs, or stems.

Know more about    characteristic  here:

https://brainly.com/question/28790299

#SPJ8

A chiral catalyst controls the production of a chiral molecule in asymmetric catalysis so that the formation of a certain stereoisomer is encouraged.

The stabilization of the transition state (ensemble) remains the main challenge in enzyme catalysis. The modification of the transition state is the source of the catalytic power. However, rather than merely a single clearly defined structure, the transition state is defined by us as the full transition-state surface.

Molecule parameters like molecular geometry, heat of formation, strain energy, dipole moment, and vibrational frequencies may be calculated empirically using molecular mechanics approach.

To know more about asymmetric catalysis, refer

https://brainly.com/question/12507566

#SPJ4

Answer:

To determine the change in mass of A over the given time period, we need to find the difference between the initial mass of A and the final mass of A.

From the given table, we can see that the initial mass of A at t = 0 (start time) is 12.4 g and the final mass of A at t = 60 minutes (end time) is 6.2 g.

Therefore, the change in mass of A over 60 minutes is:

Final mass of A - Initial mass of A

= 6.2 g - 12.4 g

= -6.2 g

The negative sign indicates that the mass of A decreased over time, which means that A underwent some kind of reaction or process that caused it to lose mass.

The change in mass of A over 60 minutes is -6.2 grams.

To determine the change in mass of A over 60 minutes, we need to compare the initial mass to the final mass.

From the given information, we can see that the mass of A decreases over time.

Let's calculate the change in mass.

Initial Mass of A: 12.4 g

Final Mass of A: 6.2 g

Change in Mass of A = Final Mass of A - Initial Mass of A

= 6.2 g - 12.4 g

= -6.2 g

The change in mass of A over 60 minutes is -6.2 grams.

Note that the negative sign indicates a decrease in mass.

For such more questions on mass

https://brainly.com/question/1838164

#SPJ8

Based on the specific heat of water, the final temperature of the liquid that is formed when 50 grams of ice and 500 g of water are mixed together is 23.3 °C.

The final temperature of the liquid that is formed when 50 grams of ice and 500 g of water are mixed together is determined as follows:

Heat change = mc(T_f - Ti)

The heat of fusion = mL

where;

Heat lost water = mc(T_f - Ti)

c for water = 4.19 J/J/(g°C)

Heat lost water = 500 * 4.18 * (T_f - 20)

Heat lost water = 2090T_f - 41800

Heat gained by ice = mc(T_f - Ti) + mL + mc(T_f - Ti)

c for ice = 2.03 J/J/(g°C)

Heat gained by ice = 50 * 2.03 * {0 - (-20)} + 50 * 0.334 + 50 * 4.18 * (T_f - 0)

Heat gained by ice = 2046.7 + 209T_f

From heat gained = heat lost;

2046.7 + 209T_f = 2090T_f - 41800

2090T_f - 209T_f = 2046.7 + 41800

1881T_f = 43846.7

T_f = 23.3 °C

Learn more about specific heat at: https://brainly.com/question/21406849

#SPJ1

Answer:

i like butting hole

Explanation:

mkrkr

Answer: Other nonmetal elements are oxygen, neon, fluorine, nitrogen, carbon, boron, chlorine, argon, and hydrogen.

Explanation:

If you look at the periodic table the elements are grouped together. For example the metals are in the middle, the nonmetals are on either sides (noble gases, earth alkaline, reactive nonmetals, and etc.)

The weather condition is NOT associated with warm fronts is: "warm fronts typically produce more violent weather than cold front" (Option A)

This is because, quite to the contrary, warm fronts are less likely to create violent weather than cold fronts. Warm fronts are connected with gradual ascension zones (i.e. stratiform clouds and precipitation).

Clouds and precipitation are common ahead of the warm front. Warm fronts travel far more slowly than cold fronts.

Weather fronts frequently indicate the type of weather that is on its way: Cold fronts, for example, provide heavier, denser air that pushes beneath the lighter warm front.

Winds grow gusty as the cold front passes. There is a sharp drop in temperature, as well as heavy rain, occasionally accompanied by hail, thunder, and lighting.

Cold fronts produce the most common type of cloud, cumulus clouds. They frequently develop into cumulonimbus clouds, which cause thunderstorms. Nimbostratus, stratocumulus, and stratus clouds can also be produced by cold fronts.

Learn more about Cold Fronts:

https://brainly.com/question/12375861
#SPJ1