Explanation:
Just like an independent variable, a dependent variable is exactly what it sounds like. It is something that depends on other factors. For example, a test score could be a dependent variable because it could change depending on several factors such as how much you studied, how much sleep you got the night before you took the test, or even how hungry you were when you took it. Usually when you are looking for a relationship between two things you are trying to find out what makes the dependent variable change the way it does.
Calculate the pH after 20.0% (by moles) of the benzoic acid is converted to benzoate anion by addition of a strong base. Use the dissociation equilibrium to calculate the pH. pH = ________
Answer:
pH = 4.79
Explanation:
The equilibrium of benzoic acid, BH, is:
BH ⇄ B⁻ + H⁺
Where B⁻ is benzoate anion
Where the dissociation equilibrium, Ka, is:
Ka = 6.46x10⁻⁵ = [B⁻] [H⁺] / [BH]
If 20.0% is B⁻, 80.0% is BH, replacing:
6.46x10⁻⁵ = [20.0%] [H⁺] / [80.0%]
1.615x10⁻⁵ = [H⁺]
As pH = -log [H⁺]
pH = 4.79When a sample of liquid is heated, its thermal energy _______.
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.
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Write the balanced chemical equation for the following reaction. Phases are optional. Solid iron(I) oxide reacts with hydrogen gas to form solid iron and liquid water. 2Fe+3H,Ol Fe,O,+ 3H2 â 2Fe+ 3H2O(I)
Answer:
[tex]Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(l)[/tex]
Explanation:
Hello!
In this case, when writing chemical reactions from the given names we must make sure we know the proper formula for each reacted and produced species; thus, since solid iron (III) oxide is [tex]Fe_2O_3[/tex], hydrogen gas is [tex]H_2[/tex], solid iron is Fe and liquid water is just [tex]H_2O[/tex], we can write:
[tex]Fe_2O_3(s)+H_2(g)\rightarrow Fe(s)+H_2O(l)[/tex]
However, since different amount of atoms of iron, hydrogen and oxygen are present at each side of the equation, we balance it by adding the following coefficients to each molecule:
[tex]Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(l)[/tex]
And now it is balanced with two iron atoms, three oxygen atoms and six hydrogen atoms at both reactants and products.
Best regards!
what is the atomic number of oxygen
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.
What is the charge on an atom after it gains two electrons during the formation of a bond?
One positive charge
Two positive charges
Two negative charges
One negative charge
Answer:
Two Negative Charges
Explanation:
C. Two negative charges
If an atom has an equal number of protons and electrons, its net charge is 0. If it gains an extra electron, it becomes negatively charged and is known as an anion. If it loses an electron, it becomes positively charged and is known as a cation.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.
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Describe the role of chloroplasts in photosynthesis. (ASAP)
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:
4)
Fluorine and element Z have similar chemical properties. Element Z could have an electron
configuration of
A)
2-2
B)
2-8-1
C)
2-8-8
D)
2-8-18-7
Answer:
D) 2.8.18.7
Explanation:
because it has 7 valence electron that occupied by shells
Select the correct answer. The perimeter of a rectangle is 42 inches. If the width of the rectangle is 6 inches, what is the length? A. 12 inches B. 15 inches C. 21 inches D. 40 inches
Answer:
15
I hope this helps
Which shows three human body parts in order from the simplest level of organization to the most complex?
red blood cell → nervous system → bone tissue
nervous system → bone tissue → red blood cell
red blood cell → heart tissue → circulatory system
bone tissue → red blood cell → nervous system
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.
What is heart?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.
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The energy of a pendulum is recorded at different positions in the table below. Use the data in the table to determine the amount of kinetic energy the pendulum had at Position 2. Record your answer below.
Please help me I just want to get this test over with
Answer:
so i got 34.5
Explanation:
Convert 98.5 Pa into mm Hg. (133.32 Pa = 1.00 mm Hg)
A 1.50 mol sample of He occupies a volume of 2.50 L at a pressure of 14.7 atm. What will be the pressure of a 1.50 mol sample of H2 gas under the same conditions? a 7.33atm b 14.7atm c 29.4 atm d 1.00 atm
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
An organic chemist is planning to extract 1.00 g of an organic compound dissolved in 200.0 mL of water into a diethyl ether solvent. The partition coefficient for this system is 9.5, favoring the diethyl ether solvent. What percentage of the organic compound remains in the aqueous solvent if you perform three successive extractions with 50.0 mL of diethyl ether for each extraction?(a) 29.63% (b) 2.60% (c) 0.00169%
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 =
(b) 2.60%A mixture of Xe, Kr and Ar has a total pressure of 6.70 atm. What is the mole fraction of Kr if the partial pressure of Xe is 1.60 atm and that of Ar is 2.80 atm.
Answer:
0.343
Explanation:
Step 1: Given data
Total pressure of the gaseous mixture (P): 6.70 atmPartial pressure of Xe (pXe): 1.60 atmPartial pressure of Ar (pAr): 2.80 atmStep 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:
Total pressure= 6.70 atm. Partial pressure of Xe is 1.60 atm. Partial pressure of Ar is 2.80 atm.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.
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brainly.com/question/14239096?referrer=searchResults brainly.com/question/25181467?referrer=searchResults brainly.com/question/14119417How many grams of N2 are required to react with 2.30 moles of Mg in the following process? 3 Mg + N2 → Mg3N2? (Mg = 24.3 g/mol, N = 14.0 g/mol)
Answer: 10.73 g
Explanation:
2.3 mol Mg * (1 mol N2 / 3 mol Mg) * (14 g Mg / 1 mol g) = 10.73
How does one determine a percent composition from an empirical
formula?
A. Divide the atomic mass of the element by its subscript and
multiply by 100%
O B. Divide the mass of the compound by the atomic mass of
the element and multiply by 100%
O C. Divide the subscript of the element by the mass of the
element and multiply by 100%
O D. Divide the total mass of each element by the mass of the
compound and multiply by 100%
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%.
What is empirical formula?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%.
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A gas has a volume of 6.00 liters at a temperature of 27° C and a pressure of 1,00 atm. What is the volume of the gas, in liters, at a temperature of 327°C and a
pressure of 3.00 atm?
We are given:
P1 = 1 atm P2 = 3 atm
T1 = 300 K T2 = 600 K
V1 = 6 L V2 = v L
Finding the final Volume:
From the ideal gas equation:
PV = nRT
since in the given scenario, the universal gas constant (R) and number of moles(n) are constant
So, for both the cases, the value of n*R will be a constant k
Hence, we can write that:
PV / T = k [where k is a constant]
Since the constant 'k' is the same for both the cases, we can write that:
P1V1 / T1 = P2V2 / T2
replacing the variables
1 * 6 / 300 = 3 * v / 600
1/50 = v / 200
v = 200/50
v = 4 L
Therefore, the volume of the gas at 600K and 3 atm will have a volume of 4 L
describe, in terms of the motion of particles in an object, how heat conduction transfers energy between objects or from one part of an object to another part at a lower temperature.
Answer:
Molecular movement
Explanation:
When an object gets hotter, its molecules gain more kinetic energy and then move faster. Therefore, the fast-moving molecules will cause those around them to move faster as well, and the colder (or more slow-moving molecule object) object or part is heated up.
PLS GIVE BRAINLIEST
Calculate the density of the rock if its mass is 360 g.
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
In the reaction of aluminum metal and oxygen to make aluminum oxide, how many grams of oxygen gas will react with 2.2 moles aluminum metal?
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.
Which is a chemical property of soda ash?
Explanation:
A chemical property of soda ash is, it is a alkaline compound
5.75 x 1021 molecules of oxygen is the equivalent of how many
moles?
765.75
................................
What is the definition of an Isomer?
Answer:
Each of two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties.
Explanation:
Density equals _____.
volume divided by mass
mass divided by volume
weight divided by area
weight divided by volume
Which statement is incorrect?
Acids produce H+ ions when ionized.
B. Bases produce OH^ lons when lonized.
C. Bases are found in the pH range of 1-7 on the pH
scale.
Distilled water has a neutral pH of 7.0.
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!
Please help me please i will mark you brainliest. In the nucleus of an atom, there are 17 protons and 18 neutrons. What is the atomic number? What is the atomic mass? How many electrons are there? Be sure to answer all 3 questions.
Answer:
i can only help with 2 :( atimic mass is: 35.453 and number of electrons is:17
Explanation:
Why is the following electron configuration not possible?
1-9-1
Answer: because its noy
Explanation:
100. g of ice at 0 is added to 300.0 g of water at 60C. Assuming no transfer of heat to
the surroundings, what is the temperature of the liquid water after all the ice has
melted?
The final temperature of the liquid water after all the ice has melted is equal to 25°C.
What is the specific heat capacity?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
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what step of the scientific method do we decide whether our hypothesis was correct or not
List what you are thankful for! (It's Thanksgiving! Answer if you bake! Or if you like cakes pies cookies and treats!!! )
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.