The precipitate is collected, filtered, dried, and weighed.. The mass of the precipitate is 0.116 g.
What is dissolved?Dissolved refers to a solute that is completely dissolved in a solvent, resulting in a homogeneous mixture. When a solute, such as a salt, is dissolved in a solvent, such as water, the molecules of each component are dispersed evenly throughout the mixture. This process can be reversed by evaporating the solvent, leaving the solute behind. The amount of solute that can be dissolved in a particular solvent is known as its solubility.
Mass of Al2(SO4)3= Mass of sample- Mass of precipitate
Mass of Al2(SO4)3= 1.68-0.116=1.564 g
Percent of Al2(SO4)3= (1.564/1.68)*100= 93.45 %
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Are CO2 and O2 inversely related?
Yes carbon dioxide and oxygen are inversely related to each other.
Bohr effect is a result of the effect of carbon dioxide has on hemoglobin affinity for oxygen. Bohr's effect describes the hemoglobin's lower affinity for oxygen secondary to increases in the partial pressure of the carbon dioxide and decreases the pH of blood. This lower affinity, in turn, enhances the unloading of oxygen into the tissues to meet the oxygen demand of the tissue.
Thus, the relationship between CO₂ and hemoglobin affinity for oxygen can be described as an inverse relationship meaning when one goes one way, and the other goes the other way.
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which of the following would not be an action-reaction pair according to newton's third law of motion? a. an oar pushes the water, and the water pushes the oar. b. a dog wags its tail, and the tail wags the dog. c. a missile pushes a gas, and the gas pushes the missile. d. a boy sits in a chair, and the floor pushes the boy.
"A boy sits in a chair and the floor pushes the boy" is not an action-reaction pair according to Newton's third law of motion.
According to Newton's third law of motion, every action which occurs in nature has an equal as well as opposite reaction. If a particular object Z happens to exert a force on another object Y then the object Y will also exert an equal as well as opposite force on object Z.
For example, when an oar pushes the water, the water also pushes the oar; when a dog wags its tail, the tail also wags the dog and when a missile pushes gas out, the gas also pushes the missile forward. All these instances involve an action-reaction pair.
Hence, option d. "a boy sits in a chair, and the floor pushes the boy" is the correct option.
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What is the density of object A (give 2 sig figs)?
The mass of the object compared to its volume
How do you calculate an object’s density?The density of an item is defined as its mass divided by its volume. Density is commonly expressed in grams per cubic centimeter (g/cm3). Remember that grams are a unit of mass and cubic centimeters are a unit of volume (the same volume as 1 milliliter).
When multiplying or dividing, the result should have the same number of significant digits as the number in the computation that has the fewest. This is the volume measurement with only two sig figs in this case, hence the density should be given as 2.9 g/cm3. The density of an item is the ratio of its mass to its volume. Density is defined as density = mass/volume, or D = m/v.
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A food worker needs to
measure the temperature of
cold-held potato salad.
Where should she check the
temperature?
If a food service employee has to check the temperature of cold potato salad, she should do so at multiple places throughout the salad
If the dish is maintained between 40 and 140 degrees Fahrenheit, potato salad can be consumed around two hours after cooking. A nice approach to keep salad fresh for a long time is to refrigerate it at 40 F. Before reaching 140 F, the hot salad can be reheated.
Addition than potatoes, the salad ingredients may contain other ingredients with varying rates of cooling. Therefore, it is necessary to take temperature readings of the potato salad at various locations.
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The complete question is-
A food worker needs to measure the temperature of cold-held potato salad where should she check the temperature
A. On the surface of the salad
B. Along the side of the salad dish
C. In multiple places throughout the salad
D. On the temperature gauge of the holding equipment
A cup of water contains 8.37 x 10^24 molecules of water. How many moles of water are in the cup?
There would be 13.9 moles of the water.
What is the number of molecules?We know that we could be able to use the Avogadro's number so as to determine the number of the molecules. this would stem from the postulation that one mole of the substances would in it about 6.02 * 10^23 molecules of the water.
We would now be able to say based on the information that have been passed above in the question;
1 mole of water would contain 6.02 * 10^23 molecules of the water
x moles of water would contain 8.37 x 10^24 molecules
x = 8.37 x 10^24 molecules * 1/6.02 * 10^23
x = 13.9 moles
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PLS HELP ME ON 4 CHEMISTRY ASAP
The percent composition of cesium weighs 100 g in a sample with total mass of 400 g is 25 %.
What is mass percent?The mass percent of an element in a compound is the contribution from the element to the total mass of the compound. It is the ratio of the mass fraction of the element to the total mass multiplied by 100.
Mass percent is a common term used to express the concentration of an ion or element in a mixture.
Given that total mass of the compound = 400 g
mass of cesium in the compound = 100 g.
Mass percent of cesium = mass of Cs/total mass
mass % = 100 /400 × 100 = 25%
Therefore, the mass % of Cs in the compound is 25%.
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Using your prior knowledge of reaction stoichiometry, what is the final percentage of each reactant remaining if each reaction went to completion? show work and reasoning to justify your answer
i) No reactant will be left as all of them have been converted to product after completion of this reaction.
ii) Final percentage of each reactant remaining if each reaction went to completion is about 99.9%.
What is molar ratio?The difference between the moles (or molecules) of reactants consumed and the moles (or molecules) of products produced in a chemical reaction is known as the molar ratio.
i) Now given the molar ratio of CV : NaOH is 1:1 . That means Equal moles of CV and NaOH are present in the solution. That means all the CV and NaOH molecules will react to form equal number of products.
So in this case, no reactant will be left as all of them have been converted to product after completion of reaction.
ii) In this case, the given NaOH : CV = 1000 : 1. That means per 1000 moles of NaOH, we have only 1 mole of CV. Now since 1 mole of CV can react with only 1 mole of NaOH, then after the reaction of this 1 mole CV, there will be no CV left . And only 999 NaOH molecules will be left in the solution
So here % CV left = 0%
% of NaOH left = 999 / 1000 × 100
% of NaOH left = 99.9 %
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Complete question is attached below
What is the main function of meter?
The main function of the meter rule is to measure the distance between the two points , it is use to measure the length.
The first unit of the length is the meter. the length is defined as the distance between the two points. the meter is used to measure the length in the international system of the units. the instrument used to measure the meter is the meter rule or the meter stick. the mete rule is also called as the ruler. before the meter rule of discovery we use the primitive methods to measure the distance.
Thus, the function of the meter is the to measure the distance between the two points.
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Which element has a violent reaction when combined with cold water ?____
Base your answers to the following questions on the electron configurations below:
(A)2s1
(B)[Ar] 3d104s24p1
(C)[Kr] 4d105s25p3
(D)[Ne] 3s2
(E)[Kr]4d105s25p6
The element with electronic configuration 2s1, which is lithium, has a violent reaction with cold water.
The most reactive metals in the periodic table are the alkali metals (Li, Na, K, Rb, Cs, and Fr); they all react with cold water violently or even explosively, displacing hydrogen. In the reduction of water to hydrogen gas (H2) and the metal ion hydroxide (OH), Group 1 Metal (M) is oxidised to its metal ions.
The second most reactive metals in the periodic table are the alkaline earth metals (Be, Mg, Ca, Sr, Ba, and Ra), which also exhibit increased reactivity in higher periods like the Group 1 metals. The only alkaline earth metal that does not react with water or steam, even when heated to a high temperature, is beryllium (Be). Furthermore, beryllium has an exterior oxide layer that is robust, which reduces its reactivity at lower temperatures.
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The reaction of solid sodium metal with gaseous diatomic chlorine produces common table salt and lots of heat. The chemical equation for this reaction is best written as
The chemical equation for this reaction is best written as: Na (s) + Cl2 (g) → NaCl (s) + Heat
What is reaction?Reaction is a process in which one or more substances are changed into one or more different substances. It is a chemical or physical change that occurs in response to a stimulus. Reactions can be used to create new materials or to break down existing materials into simpler components. They can also be used to generate energy or to store energy. Reactions can be either spontaneous or non-spontaneous, depending on the conditions in which they occur.
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Early chemists, known at the time as alchemists, had a difficult time understanding the Law of Conservation of Mass. Using the burning of wood as an example, what property of matter made this law difficult for early scientists to understand?
Different types of wood burned differently.
Wood is heavier than ash.
The fire was too bright to observe the reaction.
The gases produced escaped to the atmosphere.
Answer:
The gases produced escaped to the atmosphere.
200. 00 grams of an organic compound is known to contain 83. 884 grams of carbon, 10. 486
grams of hydrogen, 18. 640 grams of oxygen and the rest is nitrogen. What is the
empirical formula of the compound?
An empirical formula is a type of chemical formula that shows the simplest ratio of elements present in a compound, rather than the total number of atoms.
What are Atoms?
Atoms are the smallest indivisible particles that make up all matter in the universe. They consist of a nucleus containing protons and neutrons, surrounded by a cloud of electrons. Atoms make up all elements, which are the building blocks for all other forms of matter.
Step 1: Calculate the atomic mass of carbon, hydrogen, oxygen, and nitrogen.
Carbon: 12.011 g/mol
Hydrogen: 1.008 g/mol
Oxygen: 15.999 g/mol
Nitrogen: 14.007 g/mol
Step 2: Convert the mass of each element to moles.
Carbon: 83.884 g / 12.011 g/mol = 6.983 mol
Hydrogen: 10.486 g / 1.008 g/mol = 10.381 mol
Oxygen: 18.640 g / 15.999 g/mol = 1.164 mol
Nitrogen: (200.00 g - (83.884 g + 10.486 g + 18.640 g)) / 14.007 g/mol = 6.871 mol
Step 3: Divide each mole value by the smallest mole value to obtain the simplest whole number ratio.
Carbon: 6.983 mol / 6.983 mol = 1
Hydrogen: 10.381 mol / 6.983 mol = 1.485
Oxygen: 1.164 mol / 6.983 mol = 0.167
Nitrogen: 6.871 mol / 6.983 mol = 0.985
The empirical formula of the compound is CHNO.
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Draw the organic product of the following reaction between (1s 3s)-1-chloro-3-methylcyclopentane
Whenever we need to find the purity of a combination of two metals, which is known as an alloy, we use the simple formula where we find the weight of the main compound in the numerator and the weight of the total alloy In the denominator. Multiplying this by hundred gives us the purity of the metal. This is extensively used to calculate the purity of silver and gold.
The zeroth law of thermodynamics describes the state where we can say what about the movement of heat between two substances?
a. the latent heat is increasing
b. the movement of heat is rapid
c. there is no movement of heat
d. the latent heat is decreasing
e. the movement of heat is slow
There is no movement of heat. The Zeroth Law of Thermodynamics states that if two systems are in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
What is Thermodynamics?Thermodynamics is the study of energy and its transformations. It examines the relationships between heat, work, and other forms of energy. The fundamental laws of thermodynamics provide a framework for studying the behavior of systems, whether they are physical, chemical, or biological in nature. Thermodynamics helps us understand the behavior of gases, liquids, and solids and how they interact with each other. It also provides us with a way to analyze how energy is transferred and used in various processes.
In other words, no heat transfer takes place between two systems that are in thermal equilibrium.
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SEP Compare Data Look at the data in Figure 2. Which is the most
electronegative
atom? Which is the least?
The most electronegative atom is Flourine and the least is Hydrogen
How is fluorine the one with most electronegative atom?The attached image indicates how the highly electronegative Fluorine atom takes away most of the electron density (red-to-blue colored cloud) from a hydrogen–fluoride covalent bond.
An electronegative atom is an atom that has a tendency to attract electrons towards itself when it is part of a chemical bond. The most common example is the oxygen atom. The ability of an atom to attract electrons is known as its electronegativity.
The higher the electronegativity of an atom, the more it will pull electrons towards itself. The electronegativity of an atom is determined by its atomic number and the number of electrons in its outermost shell.
Therefore, the correct answer is as given above
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a chloride of rhenium contains 63.6% rhenium. what is the formula of this compound?
A chloride of rhenium contains 63.6% rhenium. the formula of this compound is Re2Cl3.
The chemical trirhenium nonachloride has the formula ReCl3, which is occasionally also written as Re3Cl9. It is a hygroscopic solid that is dark red in color and insoluble in common solvents. The substance is significant in the development of inorganic chemistry since it was the first cluster compound to have metal-metal links. [1] It serves as the raw ingredient for the production of various rhenium complexes. Rhenium is an atomic number 75 chemical element with the symbol Re. It is a heavy, third-row transition metal in group 7 of the periodic table that is silvery-gray in color. Rhenium is one of the rarest elements in the Earth's crust, with an estimated average concentration of 1 part per billion (ppb).
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at ph=0, the net charge on a polypeptide will be negative.
a. true
b. false
False. A polypeptide will have a negative net charge at ph=0.
A polypeptide is what?A peptide is a small, chemically bound chain of amino acids, usually between two and fifty amino acids (called peptide bonds). A polypeptide is a longer (51 or more amino acids) chain of connected amino acids. One or more polypeptides are used to create the proteins that are produced inside of cells.
What role does the polypeptide play?Polypeptides. Proteins are created by joining several amino acids together to form polypeptides. The coupling of two or so more polypeptides results in the formation of proteins, after which they are folded into the appropriate shape.
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At room temperature I2(s) is a molecular solid. Which of the following provides a characteristic of I2(s) with a correct explanation ?
(A) It has a high melting point because it has (B) It is hard because it forms a three-dimensional covalent network
(C)It is not a good conductor of electricity because its valence electrons are localize in bonding and nonbonding pairs. (D) It is very soluble in water because its molecules are polar.
At room temperature I₂(s) is a molecular solid. the correct explanation is : (C)It is not a good conductor of electricity because its valence electrons are localize in bonding and nonbonding pairs.
The Iodine , I₂ is the example of the molecular solid. the iodine is the good conductor of the electricity due to the valence electrons that are localized in the bonding pairs and the non bonding pairs. the iodine is the element in the periodic table with the atomic number 53. the iodine is the non metallic solid at the room temperature.
The iodine exists as the diatomic form. the each iodine molecules present as the two iodine as I₂ . this is the reason it is called as molecular solid.
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The equation shows the reaction between magnesium and sulfuric acid
Mg + HSO. → MgSO. + H
(Mg=24, H=1, S=32 0=16)
5
In this maction, what mass of magnesium sulfate will be formed when 6g of magnesium reacts
with excess sulfuric acid?
Answer:
Mg + Hso4 - Mgso4 + H
24g of magnesium- 120g of Mgso4
Xg. - 6g of Mgso4
Cross multiply
120x - 144
x = 144/120
x= 1.2g
A student performs an experiment several times to determine the enthalpy of combustion of naphthalene, an organic compound with the formula C10H8, and collects the following data: −5181. 6kJmol, −5181. 9kJmol, −5183. 5kJmol, −5180. 1kJmol, and −5184. 2kJmol. What is the relative standard deviation (RSD) for this set of data? Give the answer as a positive number
The relative standard deviation (RSD) for this set of data is 9.98.
What is the combustion enthalpy in kJ/mol?The enthalpy change that occurs when 1 mole of a substance burns (combines vigorously with oxygen) under standard state conditions is known as the standard enthalpy of combustion also known as the heat of combustion. The enthalpy of combustion of ethanol, for instance, is 1366.8 kJ/mol.
Total = -5182.6 - 5181.9 - 5183.5 - 5180.1 - 5184.2
Total = -25912.3
number of items = 5
mean = total sum / number of items
mean = -25912.3/5
mean = -5182.46
[tex]x_{i}[/tex] [tex]x_{i}[/tex]-µ ([tex]x_{i}[/tex]-µ)²
-5181.6 0.86 0.7396
-5181.9 0.3 0.09
-5181.5 -0.1 0.01
-5181.1 -0.5 0.25
-5181.2 -0.4 0.16
∑ ([tex]x_{i}[/tex]-µ)² = 1.2496
Standard deviation = √∑ ([tex]x_{i}[/tex]-µ)² /x
Standard deviation = √1.2496/5
Standard deviation = 0.499
Relative standard deviation = S x 100/x
Relative standard deviation = 0.499 ×100/5
Relative standard deviation = 9.98
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A sample of gas occupies 6.00 L at a temperature of 200 K. If the pressure remains constant and the temperature is raised to 600 K, the volume of the gas sample would be:
The Ideal Gas Law states that the volume of a gas is proportional to its temperature at constant pressure.
What is pressure?Pressure is a force that is applied to an object over an area. It is measured in units of force per unit area, such as Pascals (Pa). Pressure can be applied in a number of ways, such as by squeezing, pushing, or compressing. It can also be caused by the weight of an object, or the force of gravity. Pressure can be used to do work, such as moving an object or creating heat.
This means that if we double the temperature, we will double the volume. Therefore, if the temperature of the gas sample is raised from 200 K to 600 K, the volume of the gas sample will increase from 6.00 L to 12.00 L.
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what is the volume of 35.2g of copper when copper is 8.80 g/cm3 and the density is at 20°C?
The volume of the copper is equal to 4cm³.
What is the density?The density of the substance can be described as the substance's mass per unit of its volume. The symbol commonly used to express density is ρ and the D letter can also be used.
The mathematical formula of the density can be expressed as written below:
Density = Mass/Volume or ρ = m/V
The density of a material varies with temperature and pressure. There is a small variation for solids as well as liquids but much larger for gases. Increasing the pressure of material decreases the volume of material and thus increases its density.
Given the mass of the copper = 35.2 g
The density of the copper at 20°C, d = 8.80 g/cm³
The volume of the copper, V = mass/density = 35.2/8.80 = 4 cm³
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The pressure acting here is 3.32 atm. Then the volume of copper can be determined using ideal gas law. The volume is 3.9 L.
What is ideal gas equation ?Ideal gas equation is a combination of Boyle's law, Charle's law and Avogadro's law. The expression relating pressure, volume, temperature and number of moles of a gas is written as:
PV = nRT.
It can be rearranged as PM = dRT.
where d is the density and M be the mass.
Atomic mass of copper = 63.5 g/mol
density = 8.80 g/cm³
T = 20° C or 293 K.
Then pressure p = dRT/M
p = 8.80 g/cm³ × 0.082× 293 /63.5 = 3.32 atm
Now the weight of copper = 35.2 g
number of moles of Cu = 35.2/63.5 = 0.5 g.
Then, v = nRT/P
v = 0.5 × 0.082 × 293 /3.32 = 3.9 cm³.
Therefore, the volume of copper is 3.9 L.
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If you react 9.8 grams of Zn, how many moles of H2 can you make?
select all that apply. please help! i will mark you brainliest
Kinetic energy increases as mass increases
The shape of the mass vs energy graph shows a linear relationship
When we double the mass, we double the energy.
Interpreting a graphThe graph shown in the image is a plot of the kinetic energy of objects on the y-axis and the mass of the objects on the x-axis.
The graph is a straight line. This shows that there is a linear relationship between the two parameters - the kinetic energy and mass of objects. Thus, the kinetic energy increases as mass of objects increases, and decreases as mass of objects increases.
From the graph, when the mass of objects are doubled, there is also a double in the amount of the kinetic energy of objects.
In summary, the graph shows that:
Kinetic energy increases as mass increasesThe shape of the mass vs energy graph shows a linear relationshipWhen we double the mass, we double the energy.More on interpreting graphs can be found here: https://brainly.com/question/28418462
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4. How many molecules are in 32.6 grams of potassium oxide?
a. Go from grams to moles
b. Then moles to molecules
2.084*10^23 molecules are in 32.6 grams of potassium oxide.
What Is Molar mass ?A chemical's molar mass is its weight in grammes for one mole. A mole is a unit used to measure how many atoms, molecules, and ions are present in a substance. The number of molecules in a mole of any substance is 6.022 x 1023.
Although the terms "molecular mass" and "formula mass," which refer to molar mass specifically for molecular compounds, are frequently used interchangeably, their definitions vary according to the most reputable sources.
Molar mass of K2O is 94.196g
Given mass = 32.6g
1 mole of K2O = 94.196g
So, 32.6g will be 32.6/94.196g
i.e. 0.346moles
1 mole of K2O = 6.023*10^23molecules of
0.346moles will be 2.084*10^23 molecules
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Substances that can be dissolved in water are Group of answer choices rare. soluble. thermal. molecular.
A coffee cup calorimeter is filled with 200. 0 mL of water at 22. 1°C. A piece of metal at 48. 6°
°
C with a mass of 5. 1 g is added. The final temperature of the water in the calorimeter is 26. 8°C. The density of liquid water is 1. 00 g/mL, and its specific heat capacity is 4. 18 J/(g°C). Determine the specific heat capacity of the metal
The specific heat capacity of the metal is 35.34 J/g/°C, if the specific heat capacity of the water is 4.18 J/g/°C.
Volume of water = 200 ml
Density of water = 1 gm/ml
So the mass of the water in coffee cup, m₁ = 200×1 = 200 gm
Initial temperature of water, T₁ = 22.1°C
Specific heat capacity of water, S₁ = 4.18 J/g/°C
Mass of the metal, m₂ = 5.1 gm
Initial temperature of the metal, T₂ = 48.6°C
Final combined temperature of both, T = 26.8°C
Let the specific heat capacity of the metal = S₂
Heat gain by the water = heat loss in the metal
S₁ × m₁ × (T-T₁) = S₂ × m₂ × (T₂-T)
4.18 × 200 × (26.8-22.1) = S₂ × 5.1 × (48.6-26.8)
3929.2 = S₂ × 111.18
S₂ = 3929.2/111.18
S₂ = 35.34 J/g/°C
So, the specific heat capacity of the metal is 35.34 J/g/°C.
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What happens as you move down and to the left on the periodic table?
Travelling from left to right through a period of such a periodic table reduces the size of both atom.
Traveling from left to right inside a period of such periodic table causes the size of the atom to shrink. The number of protons and the positive nuclear energy both rise with such an increasing in the atomic number. The diameter of the atom shrinks as the nucleus draws the outermost electron.
Since they are eager to give up electrons and form cations, the substances on the left column of the periodic table possess low ionization energies.
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Determine the number of atoms of each element in the following: 3CO3
A mixture of gases contains oxygen, nitrogen, and hydrogen at 0 degrees Celsius. The partial pressure of the oxygen gas is 20 kPa, the partial pressure of nitrogen gas is 40 kPa, and the partial pressure of hydrogen gas is 14 kPa. What is the total pressure exerted
The total pressure exerted by the gas mixture is 74 kPa.
What is hydrogen?Hydrogen is an odorless, colorless, and tasteless gas that is the most abundant element in the universe. It is the lightest of all elements and is a component of many compounds, such as water and hydrocarbons. Hydrogen has the highest energy content of any common fuel, making it an attractive energy source. Additionally, it is utilised in the manufacture of fertiliser, polymers, and pharmaceuticals as well as a propellant.
This is calculated by adding up the partial pressures of each individual gas in the mixture, which in this case is 20 kPa for oxygen, 40 kPa for nitrogen, and 14 kPa for hydrogen. 20 + 40 + 14 = 74
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