An atom of nitrogen has seven electrons. Which diagram correctly represents the arrangement of these electrons?
ОА.
OB
1112
1s 11:28 1111
2p
1s 12
2p
1s 12
12s 2p
OD. 1111s 112s
112p
Ос.

Answer:

A few of the positive particles aimed at a gold foil seemed to bounce back.

Explanation:

Rutherford's experiment took the search for the structure of the atom a step further. In this experiment, a narrow beam of alpha particles emitted from a source was used to bombard a thin gold foil.

The scattering of the alpha particles was detected by a movable ZnS screen. It was found that most of the alpha particles followed a straight path through the gold foil but some were scattered through large angles and some even scattered backwards.

Following this experiment, Rutherford decided on his planetary model of the atom in which the nucleus is at the core of the atom with electrons moving round the nucleus in orbits. Rutherford was awarded a Nobel prize for this work.

Answer:

a

Explanation:

edge 2020

Answer:

C

Explanation:

The ions are first accelerated electrically, and then bended magnetically to sort them and record them.

Answer:

occur if two of the ions form an insoluble ionic compound, which precipitates out of solution

Explanation:

When two ionic compounds are dissolved in water, a double replacement reaction takes place if two of the ions form an insoluble ionic compound, which precipitates out of solution. In double displacement reaction ions switch partners. And hence, produce an insoluble precipitate.

Answer:

The answer would be C.

Explanation:

I took a test with the same question.

The activation energy is very high. Hence, option C is correct.

Activation energy is the sufficient amount of energy necessary to initiate a chemical reaction.

When sodium hydroxide (NaOH) dissolves in water, it is distributed into positively-charged sodium ions and negatively - charged hydroxide ions.

These cations and anions move around in the water, free and independent of each other, though cations tend to be surrounded more closely by anions and vice versa.

Hence, when sodium hydroxide and water will react at room temperature, the activation energy is very high.

Learn more about activation energy here:

https://brainly.com/question/2410158

#SPJ5

Answer:

Explanation:

To solve the question above we must first find the pH of the solution using the formula

pH + pOH = 14

pOH = 3.1

So we have

pH + 3.1 = 14

pH = 14 - 3.1

pH = 10.9

Since it's pH is 10.9 the solution is a basic solution since it's pH lies in the basic region.

Hope this helps you

Answer:

Lavoiser proposed a theory in charge of writing the combustion correctly, denying the phlogiston.

Lavoiser said that combustion is carried out in a medium where there is oxygen, giving as a product water and carbon dioxide.

This combustion results in the decrease in the volume of the material that burns.

Furthermore lavoiser discovered the importance of oxygen in animal respiration.

Explanation:

Lavoisier argued that if or if the presence of oxygen must be present, it is an irreversible and spontaneous process.

Answer: just trust me its c

Explanation: i dont cap

Answer:

The correct option is;

a. Delocalised electrons

Explanation:

The particles that enable electrical conductivity are the delocalised electrons

The metallic structure consists of identically shaped elements having positive ions that have a resultant alignment, surrounded by a vast array of deloclised electrons, which move freely in the metallic structure such that a metallic part usually has a high electrical conductivity.

Therefore, the freely moving delocalised electron in a metal give them the property of good conductors of electricity.

Answer:

a-Interatomic bonds

Explanation:

First of all, it is not a force. Let alone be molecular force.

Respuesta:

21.8 L

Explicación:

Paso 1: Escribir la reacción balanceada

CaCO₃ ⇒ CaO + CO₂

Paso 2: Convertir 450 g de CaCO₃ a moles

La masa molar de CaCO₃ es 100.09 g.

450 g × (1 mol/100.09 g) = 4.50 mol

Paso 3: Calcular los moles de CO₂ que se forman a partir de 4.50 moles de CaCO₃

La relación molar de CaCO₃ a CO₂ es 1:1. Los moles de CO₂ formados son 1/1 × 4.50 mol = 4.50 mol.

Paso 4: Convertir la temperatura a Kelvin

Usaremos la siguiente expresión.

K = °C + 273.15 = 200°C + 273.15 = 473 K

Paso 5: Calcular el volumen de CO₂

Usaremos la ecuación del gas ideal.

P × V = n × R × T

V = n × R × T / P

V = 4.50 mol × (0.082 atm.L/mol.K) × 473 K / 8 atm

V = 21.8 L

Answer:

29

Explanation:

Copper is a chemical element with the symbol Cu and atomic number is 29

Explanation:

Answer:

The correct answer is 15.54 kJ per degree C.

Explanation:

The enthalpy change for one mole of a substance, which combines or burns with the oxygen under the standard conditions, that is, at 25 degree C and 1 bar pressure is known as the standard molar enthalpy of combustion. The amount of heat transferred can be calculated by using the formula, q = mcΔT -------------(i)

Here q is the amount of heat transferred, c is the specific heat, ΔT is the change in temperature, and m is the mass of the substance. As in case of bomb calorimeter, mass if considered constant, thus, for calorimeter the equation mentioned will become, q = cΔT ---- (ii)

The standard molar enthalpy of combustion for carbon is -393.5 kJ/mol, that is, -393.5 kJ per mole of heat is generated by burning one mole of carbon. The molecular mass of carbon is 12 gram per mole.  

Thus, the number of moles of carbon equivalent to 0.562 grams of carbon can be determined as,  

Number of moles of carbon = mass / molecular mas

= 0.562 grams / 12 gram per mole

= 0.047 mol

The heat generated by burning 0.562 grams or 0.047 mole will be,  

q = ΔH° × number of moles

= (-393.51 kJ/mol) × 0.047 mol

= -18.49 kJ, the negative sign shows that the heat is produced.  

To find heat capacity of calorimeter, put the value of q as -18.49 kJ, for ΔT as (27.93 °C - 26.74 °C) in the equation (ii)

18.49 kJ = c × (27.93 - 26.74)

c = 18.49 kJ/1.19 °C

c = 15.54 kJ/°C

Answer:On a hot dry day humidity will be less.when humidity decreases rate of evaporation increases

Answer:

The water that evaporates from a desert cooler takes in energy from the environment for filling up for the loss of energy during EVAPORATION making the environment cold.

Therefore, on a hot dry day, the Evaporation is more which means the environment will be colder.

Explanation:

I hope it is okay.

I learnt it last year, so I went back to my book and explained it better in my own way.

Thanks.

Answer:

1a) .68 moles 1b)4.1E-23 molecules.

2a) .37 moles 2b) 2.27E-23 molecules

Explanation:

1a) CO2 is equal to 44 grams (C→12 grams,O→16 grams[·2]) .30g/44g is .68 moles.

1b) multiply 1A by advogadros number (6.022E-23)

2a) NaCl is 58 grams. 22/58 is .37 moles.

2b) multiply 2A by advogadros number.

you'd answer #3 the same way #1 and #2

The branch of science that deals with chemicals and bonds are called chemistry. The moles are units to calculate the quantity required to use the element.

The correct answer is mentioned below.

According to the question, the moles to the option is as follows:-

[tex]n =\frac{M}{M.M}\\ \\\frac{30}{44} \\\\=0.681\\\\[/tex]

The number of molecules is [tex]0.68 *6022*10^{23} =4.09496*10^{23[/tex].

2. moles of 22 grams of NaCl is

[tex]\frac{22}{44}\\ \\=0.5\\\\[/tex]

Molecules will be [tex]0.5*6.022*10^{23} = 3.011*10^{23}[/tex]

3. moles of 50-gram ammonia

[tex]\frac{50}{17} \\\\2.94\\[/tex]

The number of molecules is [tex]2.94*6.022*10^{23} = 1770*10^{23[/tex]

For more information about the moles, refer to the link:-

https://brainly.com/question/15209553

Answer:D. Oxygen gas

Explanation: because the experiment showed

Answer:

The correct option is;

The gas particles move faster, have the same molecular composition, and have weaker attractions between them than the liquid particles

Explanation:

The properties of the gas molecules in comparison to liquids are

1) The gas molecules are widely spread out

2) After evaporation and while in conditions favorable to the gaseous state, the kinetic energy of a gas is larger than the inter molecular attractive forces

3) A gas fills the container in which it is placed

For liquids

1) There are strong intermolecular forces holding the molecules together in a liquid

2) Liquid attractive forces in a liquid are strong enough to hold neighboring molecules

3) The volume of a liquid is definite.

Answer:

Photometer

Explanation:

A photometer (photo comes from the Greek for light) measures the light coming from 140,000 stars in Kepler's stationary field of view. If a planet transits (passes in front of) any star the amount of light from the star is reduced enough so that the photometer senses it and relays the information back to the Kepler team.

Scientific instruments are tools used for researching the universe and natural sciences. A Photometer is sensitive enough to detect a planet transiting a star. Thus, option D is correct.

A Photometer is a device that converts light energy into electrical voltage by the photoelectric effect given by Einstein. It uses Quantum mechanics to convert the energy possessed by the photons and electrons. It follows Ohm's law to convert energy.

It is used to detect the planets transiting stars as they can detect the light energy as it uses the electromagnetic radiation of various wavelengths to convert them by the photodiode, resistor, and a multiplier.

Therefore, option D. a photometer is used to detect the planets in the universe transiting stars.

Learn more about photometers, here:

https://brainly.com/question/15586577

#SPJ2

Your question is incomplete, but most probably your full question was, What scientific instrument is sensitive enough to detect a planet transiting a star?

Answer:

[tex]\large \boxed{\text{a)188.4 g; b) 98.67 $\, \%$}}[/tex]

Explanation:

We will need a balanced chemical equation with masses and molar masses, so, let's gather all the information in one place.

Mᵣ:                      98.08           392.18

             2Cr + 3H₂SO₄ ⟶ Cr₂(SO₄)₃ + 3H₂

To solve the stoichiometry problem, you must

a) Mass of Cr₂(SO₄)₃

(i) Mass of pure H₂SO₄

[tex]\text{Mass of pure} = \text{165 g impure} \times \dfrac{\text{85.67 g pure} }{\text{100 g impure}} = \text{141.36 g pure}[/tex]

(ii) Moles of H₂SO₄

[tex]\text{Moles of H$_{2}$SO}_{4} = \text{141.36 g H$_{2}$SO}_{4} \times \dfrac{\text{1 mol H$_{2}$SO}_{4}}{\text{98.08 g H$_{2}$SO}_{4}} = \text{1.441 mol H$_{2}$SO}_{4}[/tex]

(iii) Moles of Cr₂(SO₄)₃

The molar ratio is 1 mol Cr₂(SO₄)₃:3 mol H₂SO₄ [tex]\text{Moles of Cr$_{2}$(SO$_{4}$)}_{3} = \text{1.441 mol H$_{2}$SO}_{4} \times \dfrac{\text{1 mol Cr$_{2}$(SO$_{4}$)}_{3}}{\text{3 mol H$_{2}$SO}_{4}} = \text{0.4804 mol Cr$_{2}$(SO$_{4}$)}_{3}[/tex]

(iv) Mass of Cr₂(SO₄)₃ [tex]\text{Mass of Cr$_{2}$(SO$_{4}$)}_{3} = \text{0.4804 mol Cr$_{2}$(SO$_{4}$)}_{3} \times \dfrac{\text{392.18 g Cr$_{2}$(SO$_{4}$)}_{3}}{\text{1 mol Cr$_{2}$(SO$_{4}$)}_{3}} = \textbf{188.4 g Cr$_{2}$(SO$_{4}$)}_{3}\\\text{The mass of Cr$_{2}$(SO$_{4}$)$_{3}$ formed is $\large \boxed{\textbf{188.4 g}}$}[/tex]

b) Percentage yield

It is impossible to get a yield of 485.9 g. I will assume you meant 185.9 g.

[tex]\text{Percentage yield} = \dfrac{\text{Actual yield}}{\text{Theoretical yield}} \times 100 \, \% = \dfrac{\text{185.9 g}}{\text{188.4 g}} \times 100 \, \% = \mathbf{98.67 \, \%}\\\\\text{The percentage yield is $\large \boxed{\mathbf{98.67 \, \%}}$}[/tex]

Answer:

rabbit

Explanation:

Answer:

rabbit

Explanation:

the rabbit is the consumer because the sun "produces" the tree and mushroom, the rabbit comes along and eats the mushroom which was produced by the sun.

Answer:

The answer is "no changes in oxidation number "

Explanation:

Given equation:

[tex]3KOH + H_3PO_4 \longrightarrow K_3PO_4 + 3H_2O[/tex]

This question is incomplete, here´s the complete question.  

How does the percentage of monounsaturated and polyunsaturated fatty acids in olive oil compare to that of canola oil? Match the words in the left column to the appropriate blanks in the sentences on the right.

Olive oil has about ____ monounsaturated fats, while canola oil has about ___.

Olive oil has about ___ polyunsaturated fats, while canola oil has about ___.

6%

10%

30%

84%

5%

65%

Answer:

Olive oil has about 84% monounsaturated fats, while canola oil has about 65%.

Olive oil has about 5% polyunsaturated fats, while canola oil has about 30%.

Explanation:

Olive and canola oil are the major sources of monounsaturated fatty acids. Although vegetable oils usually have high concentrations of polyunsaturated fatty acids and less monounsaturated fats, olive and canola oils have comparatively less polyunsaturated fatty acids, and more monounsaturated fatty acids.

Answer:

Proteins

Explanation:

Amino acids act as monomers (a single unit used to form polymers) , the polymer will be a long chain of individual amino acids. An amino acid chain forms a protein. These proteins are also known as peptides.

Hope this helps and please mark as the brainliest.

you can determine this by

Answer:

603000 J

Explanation:

The following data were obtained from the question:

Energy required (Q) =...?

Mass (M) = 10000 g

Specific heat capacity (C) = 2.01 J/g°C

Overheating temperature (T2) = 121°C

Working temperature (T1) = 91°C

Change in temperature (ΔT) =.?

Change in temperature (ΔT) =T2 – T1

Change in temperature (ΔT) = 121 – 91

Change in temperature (ΔT) = 30°C

Finally, we shall determine the energe required to overheat the car as follow:

Q = MCΔT

Q = 10000 × 2.01 × 30

Q = 603000 J

Therefore, 603000 J of energy is required to overheat the car.

Answer:

0.35 g.

Explanation:

We'll begin by calculating the number of mole of Fe(NO3)3 in 35 mL of 0.250 M Fe(NO3)3 solution.

This is illustrated below:

Molarity of Fe(NO3)3 = 0.250 M

Volume = 35 mL = 35/1000 = 0.035 L

Mole of Fe(NO3)3 =?

Molarity = mole /Volume

0.250 = mole of Fe(NO3)3 / 0.035

Cross multiply

Mole of Fe(NO3)3 = 0.25 x 0.035

Mole of Fe(NO3)3 = 8.75×10¯³ mole

Next, we shall determine the number of mole of KOH in 55 mL of 0.180 M

KOH solution. This is illustrated below:

Molarity of KOH = 0.180 M

Volume = 55 mL = 55/1000 = 0.055 L

Mole of KOH =.?

Molarity = mole /Volume

0.180 = mole of KOH /0.055

Cross multiply

Mole of KOH = 0.180 x 0.055

Mole of KOH = 9.9×10¯³ mole.

Next, we shall write the balanced equation for the reaction. This is given below:

3KOH + Fe(NO3)3 —> Fe(OH)3 + 3KNO3

From the balanced equation above,

3 moles of KOH reacted with 1 mole of Fe(NO3)3 to produce 1 mole of Fe(OH)3.

Next, we shall determine the limiting reactant. This can be obtained as follow:

From the balanced equation above,

3 moles of KOH reacted with 1 mole of Fe(NO3)3.

Therefore, 9.9×10¯³ mole of KOH will react with = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(NO3)3.

From the above illustration, we can see that only 3.3×10¯³ mole out of 8.75×10¯³ mole of Fe(NO3)3 given is needed to react completely with 9.9×10¯³ mole of KOH.

Therefore, KOH is the limiting reactant and Fe(NO3)3 is the excess reactant.

Next, we shall determine the number of mole of Fe(OH)3 produced from the reaction.

In this case, we shall use the limiting reactant because it will give the maximum yield of Fe(OH)3 as all of it is consumed in the reaction.

The limiting reactant is KOH and the mole of Fe(OH)3 produce can be obtained as follow:

From the balanced equation above,

3 moles of KOH reacted to produce 1 mole of Fe(OH)3.

Therefore, 9.9×10¯³ mole of KOH will react to produce = (9.9×10¯³ x 1)/3 = 3.3×10¯³ mole of Fe(OH)3.

Finally, we shall convert 3.3×10¯³ mole of Fe(OH)3 to grams. This can be obtained as follow:

Molar mass of Fe(OH)3 = 56 + 3(16 + 1) = 56 + 3(17) = 107 g/mol

Mole of Fe(OH)3 = 3.3×10¯³ mole

Mass of Fe(OH)3 =?

Mole = mass /Molar mass

3.3×10¯³ = Mass of Fe(OH)3 / 107

Cross multiply

Mass of Fe(OH)3 = 3.3×10¯³ x 107

Mass of Fe(OH)3 = 0.3531 ≈ 0.35 g.

Therefore, 0.35 g of Fe(OH)3 was produced from the reaction.

Answer:

The evidence that demonstrated that the Chlorine in the stratosphere is believed to come primarily from CFCs ( Chlorofluorocarbons) rather than from natural sources such as volcanoes was due to the study conducted in which the amount of chlorine in the stratosphere over the past 20 years was measured and it was discovered that there was an increase over the years. This also corresponded with a rise in CFCs over the same period which shows that the chlorine in the stratosphere was from man made chemicals such as chlorofluorocarbons.

Chlorine in the stratosphere is primarily from man-made chemicals rather than from natural sources such as volcanoes is evident as follows;

Discussion;

Most of the chlorine in the stratosphere is there as a result of human activities, as the figure below illustrates.

Many compounds containing chlorine are released at the ground.

Volcanoes can emit large quantities of hydrogen chloride, but this gas is rapidly converted to hydrochloric acid, which dissolves in rain water, ice, and snow and does not reach the stratosphere.

Read more:

https://brainly.com/question/22776037

Answer:

Inverse proportion occurs when one value increases and the other decreases. For example, more workers on a job would reduce the time to complete the task. They are inversely proportional.

Answer:

A

Explanation: