Answer:
Clastic or detrital sedimentary rocks are made from pieces of bedrock, sediment, derived primarily by mechanical weathering.
Explanation:
How many short columns are on the periodic table?
Answer:
They are 4 short column on the periodic table
5. (a-c) In the balanced equation below, how many grams of solid iron can be formed if 50.0g Fe2O3 reacts with 10.0g of CO?
Fe2O3(s) + 3CO(g) → 2Fe(s) +3CO2
a. What mass of the excess reactant remains after the reaction occurred?
b. If you conducted an experiment and 11.5 grams of Fe(s) was formed what would be the percent yield?
c. If the percent yield for the process to obtain 75 kg of CO2 was 80.7%, how many kg of CO is needed?
From the balanced equation of the reaction, the mole ratio of the reactants is 1:3.
Mole of 50.0 g [tex]Fe_2O_3[/tex] = 50/160 = 0.3125 mol
Mole of 10.0 g CO = 10/28 = 0.3571 mol
Stoichiometric equivalent of [tex]Fe_2O_3[/tex] = 0.3571/3 = 0.1190 mol
In other words, [tex]Fe_2O_3[/tex] is in excess.
Excess mole = 0.3125 - 0.1190 = 0.1935 mol
Mass of 0.1935 mol [tex]Fe_2O_3[/tex] = 0.1935 x 160 = 30.96 grams
Mole ratio of CO to Fe = 3:2
Equivalent mole of Fe that would be formed = 0.3571 x 2/3
= 0.2381 mol
Mass of 0.238 mol Fe = 0.238 x 56 = 13.328 grams
Percent yield of Fe = 11.5/13.328 x 100 = 86.28%
Mole of 75 gk CO2 = 75000/44 = 1704.55 mol
Mole ratio of CO2 and Co = 1:1
Equivalent mole of CO = 1704.55 mol
Mass of 1704.55 mol CO = 1704.55 x 28 = 47.73 kg
80.7% = 47.73 kg
100% = 100 x 47.73/80.7
= 59.14 kg
In other words, 59.14 kg of CO would be needed.
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EXPLAIN Before medical images are taken, radioisotopes are often injected into a vein in a patient’s arm, or the patient drinks a solution containing the radioisotopes. Why do
you think atoms in the body usually do not emit radiation?
Answer: adioisotopes, are species of chemical elements that are produced through the natural decay of atoms. Exposure to radiation generally is considered harmful to the human body, but radioisotopes are highly valuable in medicine, particularly in the diagnosis and treatment of disease.
Explanation:
Form a group and discuss the possible reasons why EA, is a positive quantity for oxygen atom.
Answer:
Possible reasons why EA, or electronegativity, is a positive quantity for oxygen atom include:
Explanation:
Use the ideal gas law to find the volume that 4.30 mol of oxygen gas occupies at 99.7 kPa and 35.0 °C.
help please
According to the ideal gas law, 4.30 molecule of o2 occupies 0.11 m³ at 99.7 kPa with 35.0 °C.
What is a straightforward definition of ideal gas law?The relationship between a gas's pressure P, volumes V, and t in the range between low pressures and extremely high temperatures, when the gas's water moves virtually independently of one another, is known as the ideal gas, also known as the perfect gas law.
PV = nRTp = pressure in PaV
= volume in m³n = number of molesR
= molar gas constant (8.31 JK⁻¹mol⁻¹)T
= temperature in Kpressure ⇒ 99.7 × 10³ Pa
temperature ⇒ 35.0 + 273 = 308
KpV = nRT
= 99.7×10³×V= 4.30×8.31×308V
=(4.30×8.31×308)/(99.7×10³3 )V
= 0.11 m³
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Please help me fill in the blanks
Sublevels are indicated by letters s, p, d, and f.
How do write Electronic configuration?
Electron configurations have a standard notation that tells you the principle energy levels and sublevels that electrons occupy. here is Sulphur:
The atomic number of Sulphur is 16.
the electronic configuration of Sulphur is 1s2 2s2 2p6 3s2 3p4.
The 4s sublevel has lower energy than the 3d sublevel,
so, it fills next.
Which four different electron configurations are there?One orbital can house a maximum of two electrons, and there are four different types of orbitals (s, p, d, and f). More electrons can be held in the p, d, and f orbitals since they contain various sublevels. According to its location on the periodic table, each element's electron configuration is distinct.
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the enthaply of formation of water is -285.8kj/mol. what can be inferred from this statement
Answer: It takes 285.8 kJ of energy to form one mole of water
Explanation:
The enthalpy of formation of a substance is the change in enthalpy that occurs when a substance is formed from its elements in their standard states. The enthalpy of the formation of water is -285.8 kJ/mol, which means that it takes 285.8 kJ of energy to form one mole of water from its elements (hydrogen and oxygen) under standard conditions. This value is negative, which means that the formation of water releases energy. This is why water is often referred to as an "exothermic" substance because it releases energy when it is formed. The negative value of the enthalpy of formation for water can be explained by the fact that the bonds formed between hydrogen and oxygen atoms in water are stronger than the bonds between hydrogen and oxygen atoms in the individual elements. This means that it takes less energy to break the bonds in the elements than it releases when the bonds in water are formed, resulting in a net release of energy.
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Answer:
This means that 285.8 kJ/mol is evolved when one mole of water is formed.
What is the enthalpy of formation?
The term enthalpy of formation has to do with the energy that is released or absorbed when a molecule of water if formed from its constituents.
The fact that the enthalpy of formation of water is -285.8 kJ/mol implies that 285.8 kJ/mol is evolved when one mole of water is formed.
Explanation:
What is the ratio between the numbers 30 and 90
1 atm = 760 torr
For isooctane:
For tetramethylbutane:
There is no other feasible arrangement of “tetramethylbutane” it is redundant in this circumstance.
What is Tetramethylbutane?Tetramethylbutane, often known as hexamethylethane, is a hydrocarbon with the chemical formula C8H18 or (H3C-)3C-C(-CH3)3. It is the most branching and compact of the several octane isomers, as well as the only one having a butane (C4) backbone.
It has a highly symmetrical structure, a high melting point, and a narrow liquid range; in fact, it is the smallest saturated acyclic hydrocarbon that emerges as a solid at 25 °C. (Cubane, C8H8, is much smaller and solid at room temperature among cyclic hydrocarbons.) It is also the most stable C8H18 isomer, with a lower heat of formation of 4.18 kcal/mol (17.5 kJ/mol) than n-octane, which has been related to dispersive interactions (electron correlation) between the methyl groups (protobranching).
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determine the mass of IF5 in a 15.88 L sample at 378 K and 0.935 atm
The mass of [tex]IF_5[/tex] that would be in a 15.88 L sample at 378 K and 0.935 will be 106.51 grams.
Ideal gas problemThe problem can be solved by first using the ideal gas equation to know the number of moles of the gas that is present.
PV = nRT
P = 0.935, V = 15.88 L, T = 378 K, R = 0.082
Making n the subject of the formula:
n = PV/RT
= (0.935x15.88)/(0.082x378)
= 0.48 moles of the gas
Recall that, mass = mole x molar mass
The molar mass of [tex]IF_5[/tex] is 221.89 g/mol
Mass of 0.48 moles [tex]IF_5[/tex] = 0.48 x 221.89
= 106.51 grams
In other words, the mass of [tex]IF_5[/tex] that would be in a 15.88 L sample at 378 K and 0.935 is 106.51 grams.
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Average Volume of A Drop. 15 Drops for 1 ML
Note that if the water volume (ML) in a graduated cylinder is 30.0 and the volume of a drop of water is 1.00 and the number of drops is 15, the average drop volume (ML) is 2.0 mL.
What is average drop volume?Average drop volume is a measurement of a droplet's average volume. It is employed in a wide range of applications, including laboratory experimentation, medical research, and medication delivery systems.
It aids in deciding the proper amount of liquid to utilize in a certain condition. It also aids in the creation of novel pharmaceuticals and assuring exact and constant dosing in medical treatments.
You may calculate the average drop volume by dividing the total amount of water (30.0 mL) by the number of drops (15). That is to say:
(30.0 mL divided by 15 drops = 2.0 mL/drop)
Hence where the number of drops is 15mL and the volume of one drop is 1.00mL, the average Volume of a Drop is 2.0mL
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How to solve this problem in Chemistry? I am stuck
The buffer can be made using an acid or a base.
What is a buffer?We have to know that the term buffer is the generic term that can be generally used to describe any solution that is resistant to changes in acidity and the alkalinity of the solution.
We know that we can be able to make a buffer in two ways;
1) By the use of a weak acid and its salt
2) By the use of weak base and its salt.
In each case, the pH of the solution that has been formed would not be easily changed and this is the job of the buffer.
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What mass of O2 molecules contains the same number of oxygen atoms as 14.0 g of water?
Answer:
So 0.39 moles of oxygen are produced in 14 g of water. So that's it.
Explanation:
if 3.38g of CuNO3 IS DISSOLVED IN WATER TO MAKE 0.220 M solution what is the volume of the solution in milliliters"
Answer:
To determine the volume of the solution in milliliters, we need to know the mass of CuNO3 and the concentration of the solution.
Given that 3.38g of CuNO3 is dissolved in water to make a 0.220 M solution, we can use the following formula to calculate the volume of the solution:
Volume = (Mass of CuNO3) / (Concentration of solution)
Plugging in the given values, we have:
Volume = (3.38 g) / (0.220 M)
Converting the mass to grams and the concentration to moles/liter, we have:
Volume = (3.38 g) / (0.220 mol/L)
Calculating, we find that the volume of the solution is approximately 15.36 liters.
To convert the volume to milliliters, we can multiply the volume in liters by 1000. In this case, the volume in milliliters is 15,360 ml.
Therefore, the volume of the solution in milliliters is approximately 15,360 ml.
Explanation:
For this discussion, you get to explore one specific element and share the historical context and modern day application of that element with the class. Your initial post should address the following questions about the element you chose:
1. How did the element you chose get its name and who discovered it?
2. What are the properties this element possesses that places it where it is in the periodic table?
3. Write a sufficient summary of the element in common language that could be understood by the general public.
4. Describe the implications for society, benefits, drawbacks, practicality, and reactivity of the element.
5. What are some applications and hazards of this element and how is it commonly encountered?
6. Discuss your personal thoughts regarding the element.
7. Questions to your classmates that invite discussion and further the dialogue.
8. An embedded picture that is relevant to the discussion.
9. Give a citation of an external peer reviewed resource that you would like to
My exploration in one specific element as well as the sharing of the historical context and modern day application will be focused in the element Carbon. The essay is written below
What is carbon historical context?Carbon was discovered by the ancient Egyptians, and it gets its name from the Latin word "carbo," which means "charcoal."
Carbon is a nonmetal that is located in Group 14 of the periodic table. It has a unique ability to form a wide variety of chemical compounds, which is one of the reasons it is so important in modern chemistry. Carbon has four valence electrons, which allows it to form stable chemical bonds with other elements.
Carbon is a chemical element that is found in all living things. It is a key component of proteins, DNA, and other essential biomolecules. Carbon can exist in several different forms, including graphite, diamond, and various forms of carbon-based compounds called organic molecules.
Carbon has many important implications for society. It is used as a fuel to produce energy, and it is also a key ingredient in the production of steel and other metals. Carbon is also an essential component of many plastics and other synthetic materials. However, carbon can also have negative impacts on the environment, as the burning of fossil fuels releases carbon dioxide into the atmosphere, contributing to climate change.
Carbon has many practical applications, including its use as a fuel, a structural material, and a chemical feedstock. However, carbon can also be hazardous in certain situations. For example, inhaling carbon monoxide can be deadly, and carbon dust can be explosive. Carbon is commonly encountered in many different forms, including coal, oil, and natural gas.
Personally, I think that carbon is a very interesting element with a wide range of important applications. It is fascinating to consider the role that carbon plays in the biology of living organisms, as well as its practical uses in industry and technology.
Some questions for my classmates might include: What are some other interesting properties of carbon that you have learned about? Can you think of any examples of how carbon is used in your everyday life? Do you think that the benefits of carbon outweigh the potential drawbacks?
One peer-reviewed resource that I found informative is "The Many Forms of Carbon," an article published in the journal Chemical & Engineering News. (Citation: "The Many Forms of Carbon." Chemical & Engineering News, vol. 95, no. 39, 2017, pp. 38-54.)
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46 g of glycerin were dissolved in 100 g of water. What is the freezing point of this solution?
Additional information:
М(С3Н5(ОН)3) = 92 g/mol;
Тf(Н2О) = 273.15 К;
Кf = 1.86 kg⋅К/mol.
Based on the formula to determine the freezing point depression of the solvent, the freezing point of the solution is 263.85 K.
What is the freezing point of a substance?
The freezing point of a substance is the temperature at which the liquid changes to solid without any further decrease in temperature occurring during the process.
The addition of solute substances in liquids usually lowers the freezing point of the liquid solvent.
The formula to determine the freezing point depression of solvent is given below:
ΔT = i * Kf * mwhere'
ΔT is the change in freezing point,i is the van't Hoff factor,Kf is the freezing point depression constant, andm is the molality of the solution.The molality of the given solution = moles of solute/kg of solvent
moles of solute = 46/92
mass of solvent = 100 g or 0.1 kg
Molality of solution = (46/92) / 0.1
Molality of solution = 5
for glycerine, i = 1
ΔT = ΔT = 1 * 1.86 * 5
ΔT = 9.3
The freezing point of the solution = 273.15 - 9.3
The freezing point of the solution = 263.85 K
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Hydrogen gas is produced when we
metal with hydrochloric acid:
react magnesium
Mg(s) + 2 HCI(aq) - MgCl(aq) + H2(g) 7z
(a) If 4.50 g of hydrogen gas is collected at STP, what
volume of hydrogen does
this represent?
(b) If 0.52 mol of magnesium completely reacted, what
amount of hydrogen gas (in moles) would be produced
at STP? How many grams of hydrogen iS this?
Magnesium is a metal that reacts quickly. The reaction with hydrochloric acid will result in the production of magnesium chloride and hydrogen gas.
How much hydrogen is generated by the reaction at STP?Molecules, pressure, and temperature were necessary to determine the gas's volume. We only need to determine the moles of hydrogen because temperature and pressure have already been provided. As a result, 16.8 L of hydrogen were created at STP by dissolving 13.5 g of aluminum in sulfuric acid.
How much hydrochloric acid must be present for 0.50 mol of magnesium to react?The chemistry is described below. According to the aforementioned reaction, 1 mole of magnesium and 2 moles of HCl are involved. The HCl moles are therefore 20.50mol=1mol 2 0.50 m o.
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Pls help with question a and b.
a) 1 - Trigonal planar 2 - Trigonal planar
b) 1- Linear 2 - Tetrahedral 3 - Tetrahedral
c) 1 - Trigonal planar 2 - Tetrahedral
What are the shapes?We have to know that the shapes at the various carbon atoms and other atoms would depend on the number of the electron pairs and the hybridization of the atom.
We must have to note that the shape of the atom can be found on the basis of the valence shell electron pair repulsion theory which deals with the arrangement of that electrons around the outermost shell of the central atom.
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URGENT PLEASE HELP
1) The following balanced chemical equations are for based on the combustions of various fuels. Calculate the heats of combustion for each reaction
a. C2H5OH(l) + 3O2(g) à 2CO2(g) + 3H2O(g)
b. 2C4H10(g) + 13O2(g) à 8CO2(g) + 10H2O(g)
c. C3H8(g) + 5O2(g) à 3CO2(g) + 4H2O(g)
2) Express the heats of combustion from the above reactions as energy changes per mole of fuel combusted. State the reason why energy changes are often expressed per mole of reactant.
3) An Electric Generator burns gasoline to produce electricity. The balanced equation is below:
2C8H18(l) + 25O2(g) à 16CO2(g) + 18H2O(g)
a. Calculate the energy change for the burning of gasoline.
b. If the generator produces 2000kJ of electrical energy for every mole of gasoline combusted calculate the efficiency of the generator.
Answer:
Explanation:
1) The following balanced chemical equations are for based on the combustions of various fuels. Calculate the heats of combustion for each reaction a. C₂H₂OH + ...
Calculate the mass of compound (molar mass = 256 g [tex] mol {}^{-1} [/tex] ) to be dissolved in 75g of benzene to lower its freezing point by 0.48K
( [tex]K _{f} = 5.12 \: K \: \: kg \: mol { }^{ - 1} [/tex] )
thankyou.
The mass of the compound is calculated by freezing point depression formula which is ΔTf=Kf×W₂×1000/M₂×W₁ which is equal to 3125 g.
What is a compound?Compound is defined as a chemical substance made up of identical molecules containing atoms from more than one type of chemical element.
Molecule consisting atoms of only one element is not called compound.It is transformed into new substances during chemical reactions. There are four major types of compounds depending on chemical bonding present in them.
Freezing point depression is calculated by the formula, ΔTf=Kf×W₂×1000/M₂×W₁ .Therefore,W₁=5.12×75×1000/0.48×256=3125 g.
Thus, mass of compound is 3125 g.
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Bauxite ore contains aluminum oxide, which is decomposed using electricity to
produce aluminum metal and oxygen. What mass of aluminum metal can be
produced from 125 g of aluminum oxide?
Answer:
66.48 g.
Explanation:
Bauxite ore contains aluminium oxide which is decomposed using electricity to produce aluminium metal and oxygen gas
Which of the following statements is/are incorrect regarding dilution of concentrated sulphuric acid?
Answer:
Option d) 3 only is the right answer
Osmosis.
10 % solution of sodium chloride is on the first side of the semipermeable membrane separating the vessel and 2 % solution of sodium chloride is on its other side. Describe the process taking place there.
Answer:
Osmosis is taking place in the vessel, where a 10% solution of sodium chloride is on one side of the semipermeable membrane and a 2% solution of sodium chloride is on the other side. Osmosis is a special case of diffusion, where water moves from an area of higher concentration to one of lower concentration. In this case, water will move from the 10% solution to the 2% solution, as it has a higher solute concentration. This process is known as osmoregulation and it involves maintaining salt and water balance across membranes within the body’s fluids. The key to remember about osmosis is that water flows from the solution with the lower solute concentration into the solution with higher solute concentration. As such, in this case, water will flow from the 2% solution to the 10% solution.
Explanation:
What is the name of the ionic compound formed from lithium and bromine?
Why is the answer lithium bromide? What is the indicator that this is the correct name, rather than lithium bromate? Is this because a compound would need to contain 3 different atoms and oxygen to have the name lithium bromate? Is that why NaNO3 is Sodium Nitrate?
Answer:
The answer is lithium bromide because it is the combination of a metal (lithium) and a nonmetal (bromine). The indicator that this is the correct name, rather than lithium bromate, is that the compound is composed of only two elements and does not contain oxygen. Yes, this is why NaNO3 is Sodium Nitrate; it is composed of three different elements (sodium, nitrogen, and oxygen).
Explanation:
Conduct research to identify two naturally occurring radioactive elements and two synthetic radioactive elements.
Natural radioactive elements are those that spontaneously radiate in nature and have an atomic number between 82 and 92. In dirt, air, water, rocks, plants, food, uranium—a radioactive element—can be discovered.
What makes certain substances radioactive?When an element's atoms contain excess neutrons or protons, the extra energy produced in the nucleus causes the atom to lose its equilibrium or become unstable. if and how radioactive particles can become stable. Radiation is produced by radioactive atoms' unstable nuclei.
What radiation is the most dangerous?Compared to beta and gamma particles, alpha particles represent the most dangerous internal threat. The most hazardous methods of exposure to radioactive elements that release alpha and beta radiation are ingestion, inhalation, absorption, and injection. Gamma radiation is the outside hazard that causes the most damage.
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use the kinetic particle model to describe the motion and separation of the particles in solid carbon dioxide and carbon dioxide gas
In solid carbon dioxide (dry ice), the particles are held together by strong covalent bonds, so they do not move around much.
What is the carbon dioxide?
Carbon dioxide (CO2) is an odorless, colorless gas created through natural processes such as respiration, combustion and the breakdown of organic materials. As a greenhouse gas, it is a major component of the Earth’s atmosphere and plays a critical role in regulating the global climate. Carbon dioxide is made up of one carbon atom and two oxygen atoms, and is produced when fossil fuels such as coal and oil are burned. Plants and trees also use carbon dioxide as part of their photosynthesis process. Carbon dioxide is essential for life on Earth, however, too much of it can have a negative impact on our planet. As human activity has increased over the past century, so too has our production of CO2, resulting in higher concentrations of this gas in the atmosphere and contributing to global warming.
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Use the data in the table below to calculate the heat of vaporization (AHvap) in kJ/mol of pinene.
Vapor Pressure
(torr)
760
515
340
218
135
Temperature
(K)
429
415
401
387
373
kJ/mol
Use the value of AHyap determined in Part 1 to calculate the vapor pressure of pinene (in torr) at room temperature (23°C)
760
torr
Answer:
41 kJ/mol4 torrExplanation:
Given pinene has a (temperature, vapor pressure) relation (K, torr) = {(373, 135), (429, 760)}, you want the heat of vaporization in kJ/mol and the vapor pressure at room temperature (23 °C).
Clausius–Clapeyron EquationThe Clausius–Clapeyron equation can be used to find the heat of vaporization:
[tex]\ln{P}=-\dfrac{\Delta H_{\text{vap}}}{R}\left(\dfrac{1}{T}\right)+C[/tex]
Solving for ∆H, we find ...
[tex]\Delta H_{\text{vap}}=-\dfrac{R\cdot\ln{\dfrac{P_1}{P_2}}}{\dfrac{1}{T_1}-\dfrac{1}{T_2}}\\\\\\\Delta H_{\text{vap}}=-\dfrac{8.314\cdot\ln{\dfrac{760}{135}}}{\dfrac{1}{429}-\dfrac{1}{373}}\approx 41052.8[/tex]
The heat of vaporization of pinene is about 41 kJ/mol.
Vapor pressureRearranging the above equation to give P1, we have ...
[tex]\ln{\dfrac{P_1}{P_2}}=-\dfrac{\Delta H_\text{vap}}{R}\left(\dfrac{1}{T_1}-\dfrac{1}{T_2}\right) \\\\\\P_1=P_2\cdot e^{-\frac{\Delta H_\text{vap}}{R}\left(T_1^{-1}-T_2^{-1})}[/tex]
Using the same P2 and T2 as above, we find the vapor pressure at room temperature (296.15 K) to be ...
P1 ≈ 4.349 . . . . . torr
The vapor pressure of pinene at room temperature is about 4 torr.
an oxygen atom, the number of nucleons is 16. What is its atomic mass?
Answer:
oxygen-16 is a stable isotope of oxygen, having 8 neutrons and 8 protons in its nucleus. It has a mass of 15. u
A student placed four magnets of equal size and mass each the same distance from an electromagnet. She turned the electromagnet on and then quickly turned it off. The diagram below shows how far each magnet traveled toward the electromagnet when the circuit was closed.
four magnets near an electromagnet
What is the order of the magnets by strength from strongest to weakest?
magnet W
magnet X
magnet Y
magnet Z
You have to put them in order
Four magnets near an electromagnet What is the order of the magnets by strength from strongest to weakest. magnet W,magnet X,electromagnet,magnet Y,magnet Z.
What is electromagnet?
An electromagnet is a type of magnet in which the magnetic field is generated by an electric current. It usually consists of a coil of wire that is wrapped around a core of magnetic material such as iron or steel.
When an electric current passes through the wire, a magnetic field is created around the core, making it a magnet. Electromagnets are used in many different applications, such as motors, generators, and speakers.
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What is the molecular weight of H2O
Answer:
18.015
Explanation:
Using the periodic table of the elements to find atomic weights, we find that hydrogen has an atomic weight of 1, and oxygen's is 16. In order to calculate the molecular weight of one water molecule, we add the contributions from each atom; that is, 2(1) + 1(16) = 18 grams/mole.