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Answer: The electronic configuration of selenium is [tex]1s^22s^22p^63s^23p^64s^23d^{10}4p^4[/tex]

Explanation:

The atomic number is defined as the number of protons or number of electrons present in a neutral atom.

Number of electrons will be equal to the atomic number of an atom.

Electronic configuration is defined as the representation of electrons in an atom.

Selenium is the 34th element of the periodic table.

The electronic configuration of Selenium is [tex]1s^22s^22p^63s^23p^64s^23d^{10}4p^4[/tex]

It has 6 electrons that are present in the outermost shell.

Answer:

I hope that's what u were lookong for :))

Explanation:

Answer: The statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.

Explanation:

When particles or atoms of a substance are able to move rapidly from one place to another then it is called diffusion.

During diffusion, particles tend to move apart from each other.

For example, spreading of dye molecules into water.

Thus, we can conclude that the statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.

Answer:

Explanation:

Lead Monoxide: PbO

Nitric Acid: HNO3

PbO + 2 HNO3 ---> Pb(NO3)2 + H2O

Answer:

Explanation:

mono mean single so lead monoxide is PbO

nitric acid is HNO3

both Pb n O are double-charged while H n NO3 are single

so balanced eqn is:

PbO + 2HNO3 -> Pb(NO3)2 + H2O

Answer:

the moving of something form it's places or position

Answer:

See explanation

Explanation:

First we must obtain the limiting reactant. The equation of the reaction is;

CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (g)

Number of moles of CH4= 28.6 g/16g/mol = 1.8 moles

Since the reaction is 1:1, 1.8 moles of CO2 was produced

Number of moles of O2 = 57.6 g/32 g/mol = 1.8 moles

2 moles of O2 produced 1 mole of CO2

1.8 moles of O2 produced 1.8 × 1/2 = 0.9 moles of CO2

Hence O2 is the limiting reactant

Mass of CO2 produced = 0.9 moles × 44 g/mol = 39.6 g

%yield = 32.1g/39.6 g × 100

%yield = 81.1%

According to the reaction equation;

2moles of O2 reacts with 1 mole of CH4

1.8 moles of O2 reacts with 1.8 × 1/2 =0.9 moles of CH4

Number of moles of CH4 left = 1.8 moles - 0.9 moles

Number of moles of CH4 left = 0.9 moles

Answer: Decomposition is the answer

Explanation: why because aluminium hydroxide would decomposes in the presence of heat and would form an oxide which is aluminium oxide and would also form water as a product.

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Answer:

The kinetic energy of the electron just before the collision is 9.3 eV.

Explanation:

We can find the kinetic energy of the electron before the collision can be found by energy conservation:

[tex] E_{i} = E_{f} [/tex]

[tex] K_{a_{i}} + K_{e_{i}} = K_{a_{f}} + K_{e_{f}} [/tex]   (1)

Where:

[tex]K_{a_{i}}[/tex]: is the initial kinetic energy of the atom

[tex]K_{a_{f}}[/tex]: is the final kinetic energy of the atom = 6.1 eV + [tex]K_{a_{i}}[/tex]

[tex]K_{e_{i}}[/tex]: is the initial kinetic energy of the electron =?

[tex]K_{e_{f}}[/tex]: is the final kinetic energy of the electron = 3.2 eV

By solving equation (1) for [tex]K_{e_{i}}[/tex] we have:

[tex]K_{a_{i}} + K_{e_{i}} = (6.1 eV + K_{a_{i}}) + 3.2 eV[/tex]

[tex] K_{e_{i}} = 6.1 eV + 3.2 eV = 9.3 eV [/tex]

Therefore, the kinetic energy of the electron just before the collision is 9.3 eV.

I hope it helps you!

Answer:

A

Explanation:

I think that is the ans but am not sure

Answer:

2-methylpropan-1-ol.

Explanation:

[tex]{ \tt{CH _{3}CH(CH _{3})CH _{2}OH}}[/tex]

Answer:

D. Burning a peice of wood

Explanation:

Because when you burn wood a chemical reaction happenes between the flames and the wood making the wood into ashes.

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The dissolving salt in water is an an example of a chemical change. The correct option is A.

A chemical change, also known as a chemical reaction, is the production of new substances with changing chemical compositions and characteristics.

In water, sodium chloride dissociates into Na+ ions and Cl- ions, which may be described as a chemical process.

The ionic connections between the atoms are broken as salt dissolves. Because the reactant (sodium chloride or NaCl) varies from the products (sodium and chloride ions), a chemical reaction takes place.

Thus, the correct option is A.

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Answer:

He blasted alpha rays at the gold foils. The Alpha rays are charged positive. When he blasted them the protons deflected and changed the course of them and the electrons surrounding the atom let them through. In the plum pudding model they were supposed to be sprinkled on which was clearly wrong according to that experiment.

Explanation:

Answer:

In after fasting test, Person 2 has slightly higher blood glucose level than person 1.

In after drinking glucose test, Person 3 has much high glucose level than person 1.

Explanation:

Blood sugar test determines the level of glucose present in body. The test can be taken after intake of food / glucose or after fasting for 12 hours. Results of both tests are compared to identify level of glucose present in human body. In after fasting test person has higher glucose and in another test person 3 has higher glucose level.

Answer:

it is option (d)

it has more mass than any of the other planets of the inner solar system

Answer:

27.9 g

Explanation:

CsF + XeF₆ → CsXeF₇

First we convert 73.1 g of cesium xenon heptafluoride (CsXeF₇) into moles, using its molar mass:

As 1 mol of cesium fluoride (CsF) produces 1 mol of CsXeF₇, in order to produce 0.184 moles of CsXeF₇ we would need 0.184 moles of CsF.

Now we convert 0.184 moles of CsF to moles, using the molar mass of CsF:

Answer:

P2 = 900 mmHg.

Explanation:

Given the following data;

Initial pressure = 450 mmHg

Initial temperature = 100°C

Final temperature = 200°C

To find the final pressure, we would use Gay Lussac's law;

Gay Lussac states that when the volume of an ideal gas is kept constant, the pressure of the gas is directly proportional to the absolute temperature of the gas.

Mathematically, Gay Lussac's law is given by;

[tex] PT = K[/tex]

[tex] \frac{P1}{T1} = \frac{P2}{T2}[/tex]

Making P2 as the subject formula, we have;

[tex] P_{2}= \frac{P1}{T1} * T_{2}[/tex]

[tex] P_{2}= \frac{450}{100} * 200 [/tex]

[tex] P_{2}= 4.5 * 200 [/tex]

Final pressure, P2 = 900 mmHg.

Answer:

Inference

Explanation:

I mean, it's not difficult.

A theory is an unproven explanation.

An inference is a guess/educated guess where you don't have all the facts.

For example, if "Bob" is caught in the kitchen with a ketchup stain on his shirt, you are inferencing that he used the ketchup.

However, if you see a ketchup bottle nearby or saw it earlier, then it is not, because you already have the facts that ketchup was used.

Cu(s) + Ni(NO3)2(aq) ⇒Ni(s) + Cu(NO3)2(aq)

The answer is option B.

Electrochemical or hobby series when the electrodes (metals and non-metals) in touch with their ions are organized on the idea of the values of their preferred discount potentials or standard oxidation potentials, the resulting series is called the electrochemical.

The electrochemical series is built up by means of arranging various redox equilibria so as of their fashionable electrode potentials (redox potentials). The maximum poor E° values are placed at the pinnacle of the electrochemical series, and the maximum wonderful at the lowest.

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Answer: Different forms of chlorophyll

Explanation:

Depending on the significance the of the chlorophyll it’s function is to absorb light, which excites electrons in the chlorophyll.

Answer:

Plant cells have an organelle called chloroplast in them. Chloroplast contains a green pigment called chlorophyll which gives plants it's green color.

Chlorophyll is important in plants as it helps the plant in producing food with the process of photosynthesis.

Answer:

hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water (Kw). The concentrations of these ions in a solution are often critical determinants of the solution’s properties and the chemical behaviors of its other solutes, and specific vocabulary has been developed to describe these concentrations in relative terms. A solution is neutral if it contains equal concentrations of hydronium and hydroxide ions; acidic if it contains a greater concentration of hydronium ions than hydroxide ions; and basic if it contains a lesser concentration of hydronium ions than hydroxide ions.

Answer:

hydronium and hydroxide ions are present both in pure water and in all aqueous solutions, and their concentrations are inversely proportional as determined by the ion product of water

Explanation:

Not my work! I hope this helps!  

Answer:

2.2 × 10⁻³ mol

Explanation:

Step 1: Calculate the number of equivalents in 0.50 L of blood

The blood calcium level of 8.8 meq/L.

0.50 L Blood × 8.8 meq/L = 4.4 meq = 4.4 × 10⁻³ eq

Step 2: Calculate the number of moles of calcium

Calcium has a charge of 2. Thus, it has 2 equivalents per mole.

4.4 × 10⁻³ eq × 1 mol/2 eq = 2.2 × 10⁻³ mol

Answer:

O A. AB + CD + AC + BD

explanation:

Explanation:

A.ab+cd+ac+bd is your answer

Answer:

C = m/V

Explanation:

In order to calculate the concentration of a mixture you would need to use the formula for concentration, which is the following...

C = m/V

In this formula C is the concentration, m is the mass of the compound that is being added and mixed into the solution, and V is the total volume of the mixture. The mass of m is in terms of number of moles. Therefore, we would need more information in order to calculate the actual concentration of the mixture that you are trying to find in this scenario. Using the formula above should be enough using the values that you have in your actual workbook.

Answer: The heat energy produced is 53831.25KJ

Explanation:

METHANE is the main component of natural gas. It can undergo combustion reaction in air with a bright blue flame to produce carbondioxide and water. The heat of reaction (enthalpy) is negative because heat is absorbed during the chemical reaction. To calculate the heat energy produced by the combustion of one kilogram (1 kg) of methane the following steps are taken:

Molecular mass of methane =16 gm/mol.

So moles of 1 kg methane =

Given mass of methane ÷ molecular weight of methane

But the given mass = 1kg = 1000g

Therefore,

moles of 1000g methane = 1000÷16

= 62.5 moles

Hence, energy evolved = (moles of methane) × (heat of combustion)

Therefore,

heat energy produced= 62.5 × (-861.3kj)

= -53831.25kj

​

The heat energy produced by the combustion of one kilogram of methane is –53831.25 KJ

We'll begin by calculating the number of mole in 1 Kg of CH₄

Mass of CH₄ = 1 kg = 1000 g

Molar mass of CH₄ = 12 + (4×1) = 16 g/mol

Mole = mass /molar mass

Mole of CH₄ = 1000 / 16

CH₄ + 2O₂ —> CO₂ + 2H₂O ΔH = –861.3 KJ

From the balanced equation above,

1 mole of CH₄ reacted to produce –861.3 KJ.

Therefore,

62.5 moles of CH₄ will react to produce = 62.5 × –861.3 = –53831.25 KJ

Thus, –53831.25 KJ of heat energy is produced.

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Answer: so in this question are reactants are calcium hydroxide and ammonium chloride

Explanation: first of all know that a salt would be formed so here the salts present are calcium and chloride so they would react to form the salt calcium chloride, then since ammonium ions are present ammonia gas would be formed then, hydroxide ions (OH) are also present so water would be formed so our final products would be calcium chloride , ammonia and water .

WORD EQUATION

calcium hydroxide+ ammonium chloride⇒ calcium chloride+ ammonia+ water

CHEMICAL EQUATION

CA(OH)2+2NH4CL⇒ CACL2+2NH3+2H2O

Answer:

i hope it will help you

Explanation:

To find the formula of an ionic compound, first identify the cation and write down its symbol and charge. Then, identify the anion and write down its symbol and charge. Finally, combine the two ions to form an electrically neutral compound.