Why do some transition metals have multiple oxidation states?
Transition metals have multiple oxidation states because of their
sublevel.

Answer:

0.343

Explanation:

Step 1: Given data

Step 2: Calculate the partial pressure of Kr

The total pressure of the mixture is equal to the sum of the partial pressures of the individual gases.

P = pXe + pAr + pKr

pKr = P - pXe - pAr

pKr = 6.70 atm - 1.60 atm - 2.80 atm

pKr = 2.30 atm

Step 3: Calculate the mole fraction of Kr

We will use the following expression.

X(Kr) = pKr/P

X(Kr) = 2.30 atm/6.70 atm

X(Kr) = 0.343

Considering the Dalton's partial pressure, the mole fraction of Kr is 0.34.

The pressure exerted by a particular gas in a mixture is known as its partial pressure.

So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:

[tex]P_{T} =P_{1} +P_{2} +...+P_{n}[/tex] where n is the number of gases.

This relationship is due to the assumption that there are no attractive forces between the gases.

Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture.

So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:

[tex]P_{A} =x_{A} P_{T}[/tex]

In this case, you know:

So, replacing in the Dalton's partial pressure law:

[tex]P_{T} =P_{Xe} +P_{Ar} +P_{Kr}[/tex]

6.70 atm= 1.60 atm + 2.80 atm + [tex]P_{Kr}[/tex]

6.70 atm- 1.60 atm- 2.80 atm= [tex]P_{Kr}[/tex]

2.30 atm=[tex]P_{Kr}[/tex]

Then: [tex]P_{Kr} =x_{Kr} P_{T}[/tex]

2.30 atm= [tex]x_{Kr}[/tex] 6.70 atm

[tex]x_{Kr}[/tex] =2.30 atm ÷6.70 atm

[tex]x_{Kr}[/tex] = 0.34  

In summary, the mole fraction of Kr is 0.34.

Learn more:  

Answer:

12.0 g/mL

Explanation:

From the question given above, the following data were obtained:

Mass of Rock = 360 g

Volume of water = 150 mL

Volume of water + Rock = 180 mL

Density of Rock =?

Next, we shall determine the volume of the rock. This can be obtained as follow:

Volume of water = 150 mL

Volume of water + Rock = 180 mL

Volume of Rock =?

Volume of Rock = (Volume of water + Rock) – (Volume of water)

Volume of Rock = 180 – 150

Volume of Rock = 30 mL

Finally, we shall determine the density of the rock as illustrated below:

Mass of Rock = 360 g

Volume of Rock = 30 mL

Density of Rock =?

Density = mass /volume

Density of Rock = 360 / 30

Density of Rock = 12.0 g/mL

Thus, the density of the rock is 12.0 g/mL

Answer:

I do not bake but my mom is a professional baker.  

Explanation:

A roof over my head and a warm home.

Plenty of drinkable water.

I don't have to go hungry.

I can enjoy the small and free pleasures of life.

Access to the internet.

My friends and family.

My health.

The kindness of people I have never met before.

Answer:  The atomic number of oxygen is "O" .

Explanation:

Because Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds.

The way one determines a percent composition from an empirical formula is to divide the total mass of each element by the mass of the compound and multiply by 100%.

Empirical formula is a notation that indicates the ratios of the various elements present in a compound, without regard to the actual numbers.

The empirical formula of a compound is the simplest ratio that can exist between the constituent elements of a compound.

However, the percent composition of a compound can be determined by dividing the total mass of each element by the mass of the compound and multiply by 100%.

Learn more about empirical formula at: https://brainly.com/question/14044066

#SPJ2

Answer:

red blood cell → heart tissue → circulatory system

Explanation:

The levels of organization from the simplest level of organization to the most complex is cell, tissue, organ, organ, organ system, and organism. Red blood cells are cells, heart tissue is tissue in the heart and the circulatory system is an organ system that ensures blood, oxygen, and nutrients are flowing through the body.

Red blood cell → heart tissue → circulatory system shows the  three human body parts in order from the simplest level of organization to the most complex.

Heart is a muscular organ which is present in most of the animals , it is responsible for pumping blood via the blood vessels to the entire body.The blood which is pumped carries oxygen and nutrients along with it.Along with it on it's way back to heart it carries carbon dioxide to the lungs.

Heart has an approximate size of a closed fist and is present between the lungs in the middle compartment of the chest. It is divided in to for chambers , the upper chambers called atria and lower ones called ventricles.

The wall of the heart is made up of three layers : epicardium,myocardium and endocardium. It pumps blood with a rhythm which is determined by a group of cells which are called the pacemaker cells present in the sinoatrial node.

Learn more about heart,here:

https://brainly.com/question/16566688

#SPJ6

Answer: because its noy

Explanation:

Answer:

Two Negative Charges

Explanation:

C. Two negative charges

Given condition: An atom gains two electrons during the formation of a bond.

As we know gaining an electron results in a negative charge and here two electrons being gained.

Therefore, the charge on it after gaining two electrons will be two negative charges.

Thus, the correct option is option C.

Learn more:

brainly.com/question/7722404

Answer:

Entropy.

Explanation:

I really hope this is right! sorry if its wrong

When a sample of liquid is heated, its thermal energy: increases.

Thermal energy can be defined as the energy possessed by an object due to the movement of its particles.

Basically, the temperature of an object or system is highly dependent on thermal energy.

Hence, temperature is directly proportional to thermal energy.

Additionally, as the temperature of an object increases due to the application of heat, the thermal energy of the object increases.

In conclusion, thermal energy increases when a sample of liquid is heated.

Read more: https://brainly.com/question/22077574

Answer:

(b) 2.60%

Explanation:

Partition coefficient of the organic compound in ether is:

9.5 = Concentration in ether / Concentration in water

In the first extraction, X is the amount of organic compound extracted:

9.5 = X/50mL / (1-X)/200mL

9.5 = 200X / (50-50X)

475 - 475X = 200X

475 = 675X

X = 0.7037g are extracted.

Remains = 1g - 0.7037g = 0.2963g

Second extraction:

9.5 = X/50mL / (0.2963-X)/200mL

9.5 = 200X / (14.815-50X)

140.74 - 475X = 200X

140.74 = 675X

X = 0.2085g are extracted.

Remains = 0.2963g - 0.2085g = 0.0878g

Third extraction:

9.5 = X/50mL / (0.0878g-X)/200mL

9.5 = 200X / (4.3899-50X)

41.70 - 475X = 200X

41.70 = 675X

X = 0.2085g are extracted.

Remains = 0.0878g - 0.0618g = 0.026g remains

Percentage: 0.026g / 1g * 100 =

Answer:

Each of two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties.

Explanation:

Answer:

450 grams of Na2SO4

Explanation:

hope that helps

Answer:

Chloroplasts absorb sunlight and use it in conjunction with water and carbon dioxide gas to produce food for the plant. Chloroplasts capture light energy from the sun to produce the free energy stored in ATP and NADPH through a process called photosynthesis.

Explanation:

Answer:

The classical cell theory was proposed by Theodor Schwann in 1839. There are three parts to this theory.

Explanation:

Answer:

D) 2.8.18.7

Explanation:

because it has 7 valence electron that occupied by shells

Answer: 10.73 g

Explanation:

2.3 mol Mg * (1 mol N2 / 3 mol Mg) * (14 g Mg / 1 mol g) = 10.73

Answer:

52.8 g of O2.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

4Al + 3O2 —> 2Al2O3

From the balanced equation above,

4 moles of Al reacted with 3 moles of O2 to produce 2 moles of Al2O3

Next, we shall determine the number of mole of O2 needed to react with 2.2 moles of Al. This can be obtained as follow:

From the balanced equation above,

4 moles of Al reacted with 3 moles of O2.

Therefore, 2.2 moles of Al will react with = (2.2 × 3)/4 = 1.65 moles of O2.

Thus, 1.65 moles of O2 is needed for the reaction.

Finally, we shall determine the mass of O2 needed as shown below:

Mole of O2 = 1.65 moles

Molar mass of O2 = 2 × 16= 32 g/mol

Mass of O2 =?

Mole = mass/Molar mass

1.65 = mass of O2 /32

Cross multiply

Mass of O2 = 1.65 × 32

Mass of O2 = 52.8 g

Therefore, 52.8 g of O2 is needed for the reaction.

Answer:

so i got 34.5

Explanation:

Answer:

15

I hope this helps

Answer:

C. Bases are found in the pH range of 1-7 on the pH scale.

Explanation:

Acids are less than 7 on the pH scale, so 1-7. Bases are more than 7 on the pH scale, so 7-14. That's why C is incorrect, hope this helps!

Answer:

A cold front is moving to the north and west before a warm front moves through.

Explanation:

The blue line indicated a cold front and the red line indicates a warm front. Both lines are moving up (north) and to the left (west) on the globe. Key words are north and west, which indicates the direction of which the fronts are moving even if it is unclear of which front is before the other.

765.75

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

How do the products of chemical reactions compare to their reactants?

Answer:

The products often have completely different properties than the reactants.

The correct answer to the question is: The products often have completely different properties than the reactants.

In a chemical reaction, the reactants and products of the reaction have different properties because during the reaction, bonds were broken and new bonds were formed which generate a new substance called the product.

However, chemical equations must be balanced in order to conform to the law of conservation of matter which states that matter can neither be created nor destroyed  during a chemical reaction but can be transferred from one form to the other.    

For example, the reaction of Hydrogen gas (H₂) and oxygen gas (O₂) to produce water (H₂O)

From the equation, we can see that the reactants are gases but the product is a liquid which has a different properties from the gaseous reactants.

Therefore, the correct answer to the question is:  The products often have completely different properties than the reactants.

Learn more: https://brainly.com/question/6686296

Answer:

el n = M/m. El nº de moles = m/M

Se utiliza la fórmula general de los gases: P*V = n*R*T

P = 760/760 = 1 atm

V = 0,5 L

n = masa de Cl2/masa molecular = masa de Cl2/70

R = 0,082

T = 273 + 20º C = 293 K

1*0,5 = masa de Cl2/70*0,082*293

0,5/0,082*293 = masa de Cl2/70

0,0208 = masa de Cl2/70

masa de Cl2 = 70*0,0208 = 1,46 g

epilacion:

Suerte

The final temperature of the liquid water after all the ice has melted is equal to 25°C.

The specific heat capacity can be described as the quantity of heat needed to raise the temperature in one unit (1kg) of substance by one-degree Celcius.

The formula to show the relationship between the specific heat capacity and heat absorbed or lost is:

Q = mCΔT

Given, the amount of ice, m = 100g

The amount of water, M = 300g

The specific heat capacity of the water, C = 1 cal /g°C

The heat of fusion of ice, C = 80 cal/g

Heat given by water = Heat taken by ice + Heat taken by water formed from ice

300 × 1 ×(60 - T) = 100 × 80  + 100 × 1 ×T

18000 - 300 T = 8000 + 100 T

400 T = 10000

T = 25°C

Learn more about specific heat capacity, here:

brainly.com/question/28302909

#SPJ2

Answer:

32.5

Explanation:

2C⁴H¹⁰ needs 13 O²

5 C⁴H¹⁰ needs (13/2 × 5) O² = 32.5 O²

The answer is D, 32.5

(I took the test)