7.92g of FeSO4 • 6H2O is equal to 1.55 x 10^23 molecules.
What is molecules?Molecules are the smallest units of matter that can exist by themselves. They are composed of two or more atoms that are held together by chemical bonds. Molecules can be found in the air we breathe, the water we drink, and the food we eat. They can also be found in living organisms, like plants and animals. Molecules can be made of a variety of different atoms, such as oxygen, carbon, nitrogen, and hydrogen. They also come in different shapes and sizes, depending on the types of atoms they are composed of.
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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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Which of the following are commonly used oxidizing agents? Select all that apply. O Hydrochloric add O Sodium dichromate O Chromic acid O Sodium borohydride
Sodium dichromate and chromic acid are commonly used as oxidizing agents.
Oxidizing agents are the compounds that can either accept hydrogen or electrons from the other molecules. It is a element or compound which participates in a oxidation-reduction reaction and accept electrons from the different species. By the acceptance of electrons from other substances, oxidizing agents cause their oxidation states to become more positive. Oxidizing agents are reduced as well. They can also transfer oxygen atoms to the molecules in some of the cases. Sodium dichromate and chromic acid are used to oxidize the other inorganic salts as well as alcohols.
Hydrochloric acid is a strong acid as well as sodium borohydride is a strong reducing agent.
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One mole of methane (CH4) and one mole of oxygen (O 2) would have the same number of atoms. Question 9 options: True False
This statement is false.
One mole of methane (CH4) contains one atom of carbon and four atoms of hydrogen, for a total of five atoms. On the other hand, one mole of oxygen (O2) contains two atoms of oxygen, for a total of two atoms. Therefore, one mole of methane and one mole of oxygen do not have the same number of atoms.
It's important to note that a mole is a unit of measurement that corresponds to the Avogadro's number of atoms, ions or molecules of a substance, which is 6.022 x 10^23 atoms, ions or molecules. That means that one mole of a substance has the same number of atoms, ions or molecules but not always the same number of elements.
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acidity: rank 4-nitrophenol, 3-nitrophenol, and 4-nitro-4-methylcyclohexanol in order of acidity
Nitrophenols should be in the following order: para - > ortho - > meta -. There is one additional resonance structure in ortho- and para-nitrophenol.
The stability of the conjugate base dictates the acidity of nitrophenols (or any acid, for that matter). By examining the resonance structures, it is possible to assess the relative stability of m- and p-nitrophenols.Therefore, ortho- and para-nitrophenol are both more acidic than meta-nitrophenol as a result of resonance effects.Sort the following substances in ascending order of acidity: One is ortho-nitrophenol. Paranitrophenol 2. Para-methylphenol 3. 4 Nitrocyclohexanol An intermediary in the creation of paracetamol is 4-nitrophenol. It is then acetylated with acetic anhydride after being reduced to 4-aminophenol.
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If the amount of H2 is doubled, how many moles of H2O would have formed?
Express your answer as an integer.
If the amount of H2 is doubled, then two moles of water have been created.
Hydrogen and water molecular interactions
Since one mole of H2 is required for the synthesis of one mole of water, doubling the amount of H2 would result in the formation of two moles of H2O. Hydrogen concentration and water content are connected. Five moles of water can be created if there are five moles of hydrogen available.
Similar to this, if 10 moles of hydrogen are accessible, ten moles of water can be produced, leading us to believe that if the amount of H2 is doubled, two times as many moles of water have been formed.
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Assume you expand the group of materials you have to test to include metals. The forces that hold the atoms together in a metallic solid, or piece of metal, are referred to collectively as the "electron sea. " This is because, in a metallic solid, electrons do not stay close to a single atom, rather they move through the metal quite readily. The resulting electrostatic force between the positive nuclei of the metal atoms and the negative electrons is very strong and keeps the metal in the solid state. Given this information, describe the results you would expect to observe if you performed the melting point and conductivity tests on a metal sample
If you perform a melting point test on a metal sample, you would expect to observe that the metal has a relatively high melting point compared to non-metallic materials. This is because of the strong electrostatic forces between the positive nuclei of the metal atoms and the negative electrons, which hold the metal atoms together in a tightly packed lattice structure. As a result, a large amount of energy is required to overcome these forces and melt the metal.
Metal samples are expected to be excellent conductors of heat and electricity when a conductivity test is performed on them. This is because electrons in metallic solids move through the metal fairly easily and are free to move around the lattice structure. This free movement of electrons allows heat and electricity to easily pass through the metal, making it highly conductive.
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In biology, a system is a collection of (blank)
(each made of multicellular tissues) that together perform a major function.
In biology, a system is a collection of organs (each made of multicellular tissues) that together perform a major function.
What is the organ about?In biology, a system refers to a collection of organs that work together to perform a specific function or set of functions. Organs are structures made of multiple types of tissues that work together to perform a specific task.
These tasks can be related to maintaining homeostasis, such as the circulatory system which transports oxygen and nutrients throughout the body, or to a specific function, such as the reproductive system which is responsible for the production of offspring.
Therefore, Organs within a system are highly specialized and have specific functions, but they also work together in concert to achieve the overall function of the system. For example, the digestive system is made up of several organs including the mouth, esophagus, stomach, small intestine, and large intestine.
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Define corrosion and explain the different basis of tendency or resistance of different
metals to corrosion
Corrosion is the process of chemical or electrochemical attack of materials by their external environment.
The tendency/resistance of different metals to corrosion largely depends on the composition of the metal. Iron and steel corrode in the presence of oxygen due to oxidation, while some metals such as chromium, nickel and molybdenum provide a protective layer of oxide film on the surface of the metal which is then resistant to corrosion. Other metals such as aluminum and zinc form sacrificial oxide layers which corrode and protect the metal from becoming completely damaged.
Shown below is the phase diagram for a typical liquid mixture of two components, A and B. a What is the significance of the horizontal line between points X and Y? O The length of the line XY corresponds to the difference in boiling point of components A and B. O A boiling liquid with composition X will produce vapor with composition Y. O The point X gives the vapor composition of the less volatile component and Y gives the vapor composition of the more volatile component. The line gives the difference. O A boiling liquid with composition Y will produce a vapor with composition X. b Using the phase diagram, determine the molar composition of the vapor in equilibrium with a boiling liquid that has a composition of 40% A and 60.% B. Percentage vapor composition A= 10 % Percentage vapor composition B 90 % What is the boiling point of this liquid? Boiling point 100 °C
The line between points X and Y represents the difference in boiling points of components A and B. A boiling liquid with a composition of 40% A and 60% B will produce a vapor with a composition of 10% A and 90% B, and have a boiling point of 100°C.
The significance of the horizontal line between points X and Y on the phase diagram is that it represents the difference in boiling points of components A and B. This line indicates the point at which the vapor and liquid phases are in equilibrium. On the diagram, point X gives the vapor composition of the less volatile component, while point Y gives the vapor composition of the more volatile component.
By looking at the phase diagram, we can determine the molar composition of the vapor in equilibrium with a boiling liquid that has a composition of 40% A and 60% B. The vapor composition of the less volatile component (X) is 10%, while the vapor composition of the more volatile component (Y) is 90%. The boiling point of this liquid is 100°C.
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A ample of helium wa compreed at 35 °C from a volume of 0. 5 L to 0. 25 L where the preure i 500 mmHg. What wa the original preure?
The original pressure was 1000 mmHg.
What is pressure?Pressure is a force applied to a surface or object over a given area. Pressure can be generated in a variety of ways, including through mechanical force, electrical force, or through changes in temperature or chemical reactions. Pressure can be measured using a variety of devices, including a barometer, manometer, or gauge. Pressure is an important concept in many fields such as physics, engineering, chemistry, and medicine. It can be used to measure the force of a liquid or gas, the pressure of a liquid or gas, or the pressure at a certain depth in the ocean.
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a reaction such as A+B -> products that exhibits second-order kinetics can be studied using a large excess of one reactant. Under these conditions, the concentration of the reactant in excess will not change much during the reaction, which will exhibit _________-first-order kinetics.
a reaction such as A+B -> products that exhibits second-order kinetics can be studied using a large excess of one reactant. Under these conditions, the concentration of the reactant in excess will not change much during the reaction, which will exhibit pseudo-first-order kinetics.
A fraud or imposter is defined as something or someone that is false but attempts to pass for the real deal. Although it's typically a prefix, pseudo can refer to a faker. A pseudo-intellectual, for instance, will attempt to persuade you that he has a brilliant mind despite the fact that he does not. The fame of a pseudo-celebrity is minimal. A combining form with the meaning "false," "pretended," or "unreal," used in the creation of compound words (pseudo classic; pseudointellectual); in science, designating a close or deceptive resemblance to the following element (pseudobulb; pseudocarp); and occasionally used in the chemical names of isomers (pseudoephedrine). a person who professes to be skilled in academic or creative endeavours but lacks in-depth comprehension or critical thinking. a person who exaggerates their intelligence and engages in intelligence fraud.
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If 6.00 L of 3.00 M HCl is added to 5.00 L of 2.00 M Ca(OH)2, which species will be the limiting reactant
HCl will be the limiting reactant for the above question
When HCl and Ca(OH)2 are mixed, they react to form water and calcium chloride (CaCl2) according to the following equation: HCl(aq) + Ca(OH)2(aq) -> CaCl2(aq) + 2H2O(l). To determine which species is the limiting reactant, we need to compare the amount of HCl and Ca(OH)2 present in the reaction.The number of moles of HCl present in the reaction is given by the equation n=CV, where n is the number of moles, C is the concentration of the solution and V is the volume. Hence number of HCL moles is:
n = 3.00 M 6.00L = 18.0 moles The number of moles of Ca(OH)2 present in the reaction is given by the equation n=CV, where n is the number of moles, C is the concentration of the solution and V is the volume. So the number of moles of Ca(OH)2 is: n = 2.00 M 5.00L = 10.0 moles. The number of moles of HCl is greater than the number of moles of Ca(OH)2, so HCl will be the limiting reactant.
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Why are the elements in Groups 1 and 17 so reactive?
Fluorine as well as chlorine are among the substances in group 17. Alkali metals as well as hydrogen are both part of group 1 on the periodic table.
Group 1 elements were extremely reactive due to the fact that they only contain one valence electron. As just a result, atoms were only ever combined with some other elements present in nature.
Due to their size as well as low ionisation enthalpy, alkali metals were extremely reactive metals. Moving lower in the group causes them to become more reactive. Reactivity to air: These metals discolor when exposed to dry air because oxides create, which then react with moisture to generate hydroxides.
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Give an example of direct and indirect evidence geologists use to study the interior of the Earth
Direct evidence for the interior of the Earth comes from measurements and samples that are taken directly from the Earth's interior. This can include things like rock samples from deep mines, or measurements of seismic waves that have traveled through the Earth.
One example of direct evidence is rock samples that have been brought to the surface by volcanic eruptions or other means. These samples can provide geologists with information about the composition and structure of the Earth's interior. For example, by studying the minerals in a rock sample, geologists can infer the temperatures and pressures that existed in the Earth's interior when the rock was formed.
Indirect evidence, on the other hand, is information that has been inferred from measurements or observations that are not taken directly from the Earth's interior. One example of indirect evidence is the study of seismic waves, which are waves of energy that travel through the Earth's interior in response to earthquakes or other disturbances. By measuring the speed at which these seismic waves travel through the Earth, geologists can infer the density and composition of the materials that make up the Earth's interior.
The volume of a given mass of gas varies inversely as its pressure. If the volume is 10dm3 when the pressure is 6atm, Find the pressure when the volume is doubled.
To solve this we must be knowing each and every concept related to ideal gas equation. Therefore, the pressure when the volume is doubled is 3atm.
What is ideal gas equation?Ideal gas equation is the mathematical expression that relates pressure volume and temperature.
Mathematically the relation between Pressure, volume and temperature can be given as
PV=nRT
where,
P = pressure of gas
V= volume of gas
n =number of moles of gas
T =temperature of gas
R = Gas constant = 0.0821 L.atm/K.mol
rearranging the above equation, we get
P₁V₁= P₂V₂
{ (6atm) (10dm[tex]_3[/tex])} ={ ( P₂) (20dm[tex]_3[/tex])}
P₂ = 3atm
Therefore, the pressure when the volume is doubled is 3atm.
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How does glycolysis make 32 ATP?
Both anaerobic and aerobic conditions can result in glycolysis. Pyruvate joins the citric acid cycle under aerobic conditions and proceeds through oxidative phosphorylation, which results in the net synthesis of 32 ATP molecules.
What is an example of anaerobic activity?Anaerobic exercises require small bursts of energy and are finished rapidly while exerting maximum effort. Examples include jumping, jogging, and hard weightlifting. Your breathing and heart rate alter as you engage in aerobic vs anaerobic activities. During aerobic workouts, oxygen is your major source of energy.
What exactly does it mean to be anaerobic?Anaerobic means "without oxygen," whereas aerobic indicates the existence of oxygen. Both are important for your overall health since they put your body through different difficulties. Anaerobic exercise consists of short bursts of high-intensity activity that do not demand your body to consume oxygen as it would during cardio (or aerobic) exercise.
Here,
Glycolysis can occur under both anaerobic and aerobic settings. Under aerobic circumstances, pyruvate enters the citric acid cycle and goes through oxidative phosphorylation, resulting in the net production of 32 ATP molecules.
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Which type (or types) of crystalline solid is characterized by each of the following: (a) high mobility of electrons throughout the solid; (b) softness, relatively low melting point; (c) high melting point and poor electrical conductivity; (d) network of covalent bonds?
Types of crystalline solids characterized by;
(a) high mobility of electrons throughout the solid; metallic solids.
(b) softness, relatively low melting point; covalent network solid.
(c) high melting point and poor electrical conductivity; ionic solids.
(d) network of covalent bonds; molecular solids.
What are the types of crystalline solids?Crystalline solids are those that have their atoms, ions, or molecules arranged in a regular, well-defined pattern. The unit cell is the smallest repeating pattern of crystalline solids, and unit cells are similar to bricks in a wall in that they are all identical and repeating.
Ionic solids, molecular solids, network covalent solids, and metallic solids are the four types of crystalline solids. A covalent network solid is a type of solid that has a low melting point, softness, and low electrical conduction. Metal cations are surrounded by a "sea" of mobile valence electrons in metallic crystals.
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(a) The student made two mistakes in setting up the apparatus.
Identify the two mistakes.
Describe the problem each mistake would cause.
The first mistake that the student made is drawing the start line with ink. So it will run/dissolve in the solvent / split up
The second mistake that the student made is placing the solvent above the spots or start line instead of under them. So they will mix with solvent or wash off paper or color the solvent or dissolve in the solvent.
In the first mistake, there is no clear, visible starting line for the experiment as the ink flows or dissolves in the solvent. This error can lead to confusion and inaccuracy in results as students cannot accurately measure or compare the progress of their experiments.
The second mistake, it mixes or washes away the solvent with the dirt and starts the line, making it difficult or impossible to observe or measure the progress of the experiment. This error can also lead to inaccuracies in results, as students may not be able to accurately measure or compare the progress of their experiments.
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Potassium(k)=1s22s22p63s23p64s
it’s asking for the electron configuration
The atomic number of Potassium(K) is 19
Knowing the number of electrons in the K atom is necessary before we can write the potassium(K) electron configuration.
There are 19 electrons. All 19 electrons will be positioned in orbitals surrounding the nucleus of the potassium(k) atom when the configuration is written.
there are some steps:
The initial two electrons in the configuration for potassium(k) will be in the 1s orbital.The following two electrons for potassium enter the 2s orbital since the 1s orbital can only accommodate two electrons. Then the 2p orbital receive the six electrons. The p orbital has room for up to six electrons. The first Six electrons will be positioned in 2p orbital, while the next two will be positioned in the 3s. As the 3s are currently full, we'll switch to the remaining six electrons to the 3p.Now we change the 4s orbital and add the final electron.To know more about Orbital, click here:
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What is the relative rate of diffusion of CH4 and NO2?
Answer:
=32×1632×√1632=34√2.
Explanation:
The poles of an electromagnet can even be reversed by reversing the flow of electricity true or false
By reversing the flow of electricity, the poles of an electromagnet may be reversed. As a result, the following statement is true.
An electromagnet is a magnet that uses electricity to operate. In contrast to a permanent magnet, the strength of an electromagnet may be readily altered by varying the amount of electric current flowing through it. By reversing the flow of electricity, the poles of an electromagnet can even be reversed.
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What is the height of a column of water which can be supported by a pressure of exactly 1 bar (=100 kPa = 750.0 mmHg) at 25 ℃?
Answer:
10.33 meters (33.78 feet).
Explanation:
1 bar = 10.33 mH₂O, 1 mH₂O = 0.098 bar, hence 10.33 mH₂O/0.098 bar = 10.33 m.
Which action characterized Earth's earliest atmosphere (atmosphere I) ?
Helium and hydrogen gases escaped earth's gravity.
Increased oxygen allowed reptiles to thrive.
Heat energy was retained and water vapor condensed.
Ultraviolet light split water vapor into hydrogen and oxygen
The action "Heat energy was retained and water vapor condensed." characterized Earth's earliest atmosphere (atmosphere I)
Earth's earliest atmosphere, also known as atmosphere I, was primarily composed of methane, ammonia, and water vapor. The heat energy from the young Earth's molten surface caused these gases to rise and cool, leading to the condensation of water vapor and the formation of oceans. This process is known as the "greenhouse effect," as the retained heat energy allowed for the formation of a hospitable environment for the emergence of life. Ultraviolet light from the sun also played a role in the formation of the atmosphere by breaking down water vapor into hydrogen and oxygen, but this was not the primary process that characterized atmosphere I.
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A double replacement reaction will occur is a precipitate is formed, or a gas is formed, or a ________ is formed.
A double replacement reaction will occur is a precipitate is formed, or a gas is formed, or a solvent is formed.
What is solvent?Solvent is a substance that is capable of dissolving other substances, resulting in a homogeneous mixture. Solvents are used in many industrial and household processes, including cleaning, extraction, and purification. Common solvents include water, alcohols, ketones, acids, and bases. Solvents can be used to dissolve both organic and inorganic substances. They are often used to separate mixtures of different substances, as well as to dissolve and purify them. Some solvents are miscible with one another, while others are not. Solvents can also be used to dissolve and disperse solids in a liquid.
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How many moles is 25g?
25 grams of a substance is equivalent to 0.0088 moles. To calculate the number of moles, the following equation can be used:
Number of moles = mass (in grams) / molar mass
The molar mass is the mass of 1 mole of a substance and is expressed in grams/mol. It is equal to the sum of the atomic masses of all the atoms in a molecule.
To calculate the number of moles from 25 grams, the molar mass of the substance must be known. Once the molar mass is known, the equation can be used to calculate the number of moles.
For example, if the substance is sodium chloride (NaCl), the molar mass is 58.44 g/mol. Applying the equation above, the number of moles can be calculated as 25 g / 58.44 g/mol = 0.0088 moles.
In conclusion, 25 grams of a substance is equal to 0.0088 moles. The molar mass of the substance must be known to calculate the number of moles from a given mass. Once the molar mass is known, the equation can be used to calculate the number of molecules.
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Graph the system on a separate sheet of paper and determine the number of solutions it has one solution If it has one
determine its coordinates.
2x + 3y = 12
2x - y = 4
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What group could X be in if it forms ions with ammonium in the ratio of (NH4)3X?
X could be in Group
If it forms ions with ammonium in the ratio of (NH4)3X, X could be in Group IV A. Group IVA (14) metals form cations with +4 charge, although tin (Sn) and lead (Pb) can form cations having +2 charge.
What does the term "coordinate bond" mean?A covalent link (a shared pair of electrons) in which both electrons originate from the same atom is known as a coordinate bond (also known as a dative covalent bond). Two atoms sharing a pair of electrons make a covalent connection. Because the electron pair is drawn to both nuclei, the atoms are kept together.
How is a coordinate bond recognized?An arrow pointing from the donor to the acceptor, with a positive charge on the donor and a negative charge on the acceptor, is used to symbolize a coordinate bond.
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A 36-gram sample of water has an initial temperature of 220C. After the sample absorbs 1200 joules of heat energy, the final temperature of the sample is
The specific heat of water is equal to 1200 joules / (36 grams × (240C - 220C)) = 16.7 joules/gram・°C.
What is temperature?Temperature is a measure of the average kinetic energy of the particles in a material. It is measured in degrees on the Celsius, Kelvin and Fahrenheit scales. Temperature is an important factor in many physical and chemical processes, such as the rate of chemical reactions, the speed of sound, the intensity of light and the properties of gases.
The specific heat of water, c, is calculated using the equation c = Q / (m × ΔT), where Q is the amount of heat energy, m is the mass of the sample and ΔT is the change in temperature.
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Calculate the molality of each of the following aqueous solutions (a) 2. 50 m nacl solution (density of solution = 1. 08 g/mL) (b) 48. 2 percent by mass KBr solution
The molarity of 2. 50 m NaCl solution is 2.68 molal and 48. 2 percent by mass KBr solution is 7.82 m.
Molality = moles solute / kg solvent
Assume we have 1000 ml of solution.
1000 ml ₓ 1.08 g/ml = 1080 g
Now find the mass of NaCl:
2.50 M NaCl = 2.50 mol/L and 2.50 mol/L x 1 L = 2.50 moles of NaCl
molar mass NaCl = 58.4 g/mol, therefore mass NaCl present = 2.50 mol ₓ 58.5 g/mol = 146 g NaCl
Now find the mass of H₂O:
grams H₂O present = 1080 g - 146 g = 934 g H2O = 0.0.934 kg
We now have moles NaCl and kg H₂O
Molality = 2.50 mol / 0.934kg = 2.68 molal
48.2% by mass of KBr means 48.2 g KBr / 100 g solution
To find molality, we need moles of KBr and kg of H₂O. We can easily find he moles of KBr from the mass and the molar mass.
If we have 100 g solution, 48.2 g is KBr so the rest is H₂O.
100 g - 48.2 g = 51.8 g H₂O and this is equal to 0.0518 kg H₂O
Moles KBr = 48.2 g KBr ₓ 1 mol KBr/119 g = 0.405 moles KBr
Molality = 0.405 moles KBr / 0.0518 kg H₂O = 7.82 m
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How will you justify presence of 18 elements in 5th period and presence of 32 elements in 6th period?
The orbitals within subshells are filled in the sequence of increasing energy. The filling can choose from the 5s, 4d, as well as 5p sub-shells. Consequently, there are 18 total components in period 5.
There are 18 atoms in the 5th grade of the periodic table, never 32. Reason l=0, 1, 2, and 3 and n=5. The energy of the accessible electron shells 4d, 5s, and 5p grows in the correct sequence: 5s4d5p. and since there are a total of 9 accessible orbitals, 18 electrons could fit.
The fourth period includes 18 elements owing to the 10 extra electrons which the 3d orbitals can hold since the 3d sublevel doesn't really fill before the 4s sublevel.
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