Answer:
This is true. A seismograph measures the size of a volcano eruption by detecting the vibrations that are produced by the volcanic activity. The vibrations can then be converted into a numerical value that represents the magnitude of the eruption.
Explanation:
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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If a sample of pure hydrogen gas is ignited very carefully, the hydrogen burns gently, combining with the oxygen gas of the air to form water vapor. Write the unbalanced chemical equation for this reaction.
H₂ (g) + O₂ (g) ⇒ H₂O (g) because Hydrogen and oxygen gas both exist as diatomic molecules. The water is in gaseous state due to the heat given off by the combustion reaction.
What is combustion reaction?Combustion, often known as burning, is a high-temperature exothermic redox chemical reaction that occurs between a fuel and an oxidant, typically atmospheric oxygen, to generate oxidized, generally gaseous products in a mixture known as smoke. A combustion reaction is a type of chemical reaction that occurs when any combustible component reacts with an oxidiser to generate an oxidised product. Fires and the release of energy in the form of heat are frequently associated with combustion processes. A hydrocarbon generally combines with oxygen in most combustion processes to produce carbon dioxide and water.
Here,
Because hydrogen and oxygen gas exist as diatomic molecules, H2 (g) + O2 (g) = H2O (g). Because of the heat produced by the combustion reaction, the water is in a gaseous condition.
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A 1. 0108 g sample of an unknown nonelectrolyte is dissolved in 10. 0090 g of benzophenone and produces a solution that freezes at 35. 8 C. If the pure benzophenone melted at 48. 1 C, what is the molecular weight of the unknown compound?
The molecular weight of the unknown compound is 80.864g.
Give a definition of freezing point depression.Only the solute's concentration affects freezing point depression; the solute's mass or chemical composition have no bearing. When it's cold outside, salt is often used to prevent ice from forming on roads by lowering the freezing point of water.
Depression in freezing point is Kb x m
T(f) - T = Kb x m
48.1 - 35.8 = 9.8 x m
m = 1.255
m = moles of solute x 1000/mass of solvent
moles of solute x 1000 / 10.0090 = 1.255
moles of solute = 0.0125
moles = mass / molar mass
1.0108 / molar mass = 0.0125
molar mass = 1.0108 / 0.0125
molar mass = 80.864
so the molecular weight is 80.864g.
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A vitamin contains 9.2 x 10^23 iron atoms. How many moles of iron are in the tablet?
Answer:
Approx. 20 moles of iron.
Explanation:
There are approx.
6.022
×
10
23
iron atoms per mole of ion. This quantity, this number of iron atoms has a mass of
55.85⋅g . And of course, when we quote the mass of iron we say
55.85⋅g⋅mol−1 .
How do you stop a chemical burn from burning?
Remove dry chemicals.Remove contaminated clothing or jewelry. Bandage the burn. Rinse again if needed.
the amount of harm to the skin relies upon on how strong the chemical was, how lots of it become at the skin, and how long it become there. Chemical burns, even minor ones, can be very painful. A minor burn may heal inside a few days. however a extra extreme burn might also take weeks or maybe months to heal completely.you need to now not use ice, or even ice-bloodless water, on a burn. extreme cold carried out to a burn can further damage the tissue. to properly cool and clean a burn, remove any apparel that covers it.
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Acellus
A steel pipe measures
62. 95 feet. How many
kilometers is this?
? ] km
Be sure to round your answer to the
correct number of significant figures.
Length in km
Enter
The answer is 0.01918 kilometers.
To convert from feet to kilometers,
you must first convert feet to meters. To do this, multiply the number of feet by 0.3048. In this case, 62.95 feet multiplied by 0.3048 equals 19.18 meters To convert from meters to kilometers, multiply the number of meters by 0.001. 19.18 meters multiplied by 0.001 equals 0.01918 kilometers. Therefore, 62.95 feet is equal to 0.01912 kilometers.
To review the conversion steps more closely, starting with feet and ending with kilometers:
1. Feet (62.95) to meters (19.18): Multiply by 0.3048
2. Meters (19.18) to kilometers (0.01918): Multiply by 0.001 or divide by 1000.
Therefore, 62.95 feet is equal to 0.01918 kilometers.
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Why do the electrons stay in between the nuclei of the two hydrogen atoms chemthink
Electrons stay in between the nuclei of the two hydrogen atoms because they are attracted to the positive charge of the nuclei.
Electrons are negatively charged species, so they are attracted towards the positive charge of a nucleus.
In hydrogen atom, when both the two hydrogen atoms get close to each other then the electrons of each atom will get attracted to both the nuclei. And if both the hydrogen atoms come close to each other they will repel each other.
The energy of the two hydrogen atoms becomes less when they are together than when they are far apart.
Thus, the electrons tend to stay in between the nuclei of the two hydrogen atoms.
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Select the proper IUPAC name for the following compound, including the (R) or (S) designation where appropriate. (2R, 3S)-2.3-difluorohexane (2S, 3R)-2, 3-difluorohexane (2R, 3R)-2, 3-difluorohexane (2S, 3S)-2, 3-difluorohexane
The proper IUPAC name for the compound is (2R,3S)-2,3-difluorohexane.
It is determined by following the IUPAC nomenclature rules for organic compounds. The key points for this are:
Parent Chain: The parent chain is a hexane, which is a six-carbon chain.Position of Substituents: A first substituent is a fluoro group that is on the second carbon of the parent chain, and a second substituent is a fluoro group that is on the third carbon of the parent chain. We use the prefix di- to indicate that there are two substituents.Absolute Configuration: The compound is a chiral compound, meaning that it has non-superimposable mirror images. To indicate the absolute configuration, we assign the priority of the substituents based on the atomic number of the atom directly bonded to the carbon atom of the substituent. The prefix (2R,3S) indicates that the substituent on the second carbon is in the R configuration and the substituent on the third carbon is in the S configuration.Final IUPAC Name: The proper IUPAC name of the compound is (2R,3S)-2,3-difluorohexane.Learn more about IUPAC nomenclature here:
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Consider the following reaction: CS2(g) + 4H2(g) CH4(g) + 2H2S(g). The equilibrium constant K is about 0.31 at 900.°C. What is Kp at this temperature? A) 2.9 103 B) 3.2 10–3 C) 3.3 10–5 D) 3.0 101 E) 1.1 10–3
The Kp of the reaction as it has been shown is 2.9 × 10^3 Option A
What is the Kp?We know that the equilibrium constant is the constant that has to do with the ease with which the reactants that are in the system can be converted into the products. In this case we have been given the reaction equation as it has been shown in the question.
Let us all now bear in mind that the reaction ghat we have here is a gas phase reaction and since the reaction is a gas phase reaction the equilibrium constanta that has been given as K can also be written in terms of the partial pressures of the gasses that are present in the system and this ius the bed rock of the answer that we woulod give above. The Kp can now be written as a scientific notation as shown above.
Then;
kp = Kc/(RT)^∆n
Kp = equilibrium constant using pressure
Kc = equilibrium constant using concentration
R = gas constant
T = temperature
n= difference in number of moles
Kp = 0.31/(0.082 × 1173)^-2
Kp = 2.9 × 10^3
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Time Remaining 4 hours 45 minutes 24 seconds04:45:24 Check my workCheck My Work button is now disabledItem 15 Time Remaining 4 hours 45 minutes 24 seconds04:45:24 Protactinium-234 has a half-life of 1 minute. How much of a 400. g sample protactinium would remain after 4 minutes
After 4 minutes, 400 g of the sample would have decayed to 400 g - (200 g x 4) = 396.2 g.
What is protactinium?Protactinium (symbol Pa) is a rare, radioactive, metallic element in the actinide series of the periodic table. It has an atomic number of 91 and an atomic mass of 231. It is found in trace amounts in nature, but can be artificially produced in a nuclear reactor. Protactinium is a soft, silvery-gray metal that is soluble in acids and insoluble in bases. It has a high melting point and is moderately toxic. It has a variety of uses, including as a fuel source in nuclear reactors and in medical research.
After 4 minutes, 400 g of protactinium-234 would have decayed to approximately 396.2 g.
This is because the half-life of protactinium-234 is 1 minute, meaning that in one minute, half of the original amount (200 g) of the sample will decay.
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What is the smallest measurement you can make on the meter stick using the metric scale?
The smallest measurement you can make on the meter stick using the metric scale is the millimeter.
The millimeter is the smallest measurement on the meter stick . The millimeter is the smallest reading in the meter stick. we use the meter stick to simply measure the length. The meter reading is calibrated in the centimeters in the meter scale. the least count in the meter scale is the millimeters. we can measure the things as the length of the table or the width.
Thus, the smallest measurement in the meter stick using the meter scale is the millimeters. the symbol of the millimeters is mm.
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Mg + 2HCl --> MgCl2 + H2(g)
Assuming STP, how many moles of hydrogen gas did Carl and his partner collect if they collected 5. 6L?
Curious Carl and his lab partner were conducting a variety of experiments to produce gases: hydrogen, oxygen, and carbon dioxide. In one experiment, they added a piece of magnesium ribbon to 10 milliliters of hydrochloric acid. They observed bubbles being produced and did a variety of tests to identify the escaping gas; it proved to be hydrogen. The reaction is represented by the following equation.
A) 0. 250 moles
B) 2. 78 moles
C) 5. 60 moles
D) 11. 2 moles
5.60 moles of hydrogen gas did Carl and his partner collect if they collected 5. 6L.
Give a brief account on Moles ?The mole, also called Avogadro's number, is a unit of measurement used in chemistry to express the amount of matter. It is defined as the number of entities (atoms, molecules, ions, etc.) in a given sample of matter. The number of mole entities is known as Avogadro's number and is approximately 6,022 x 10²³. Moles can also be used to represent the number of units of matter in a chemical reaction. For example, the equilibrium equation for the reaction of magnesium and hydrochloric acid is Mg + 2HCl → MgCl₂ + H₂. This equation shows that for every mole of magnesium, 2 moles of hydrochloric acid are required to produce 1 mole of magnesium chloride and 1 mole of hydrogen gas.
In summary, a mole is a unit of measurement used in chemistry to describe the amount of substance. It is defined as the number of units in a particular sample of matter and is known as Avogadro's number. It can be used to convert between the mass and number of units of matter, and to describe the number of units of matter in chemical reactions.
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A 35.2-mL, 1.66 M KMnO 4 solution is mixed with 16.7 mL of 0.892 M KMnO 4 solution. Calculate the concentration of the fi nal solution.
The concentration of the final solution is 1.41[tex]\frac{mol}{L}[/tex].
Now, first calculate the number of moles of first solution:
[tex]M_{1} =\frac{no. of moles of solution}{total volume of solution}[/tex]
no. of moles we have to find
total volume is 0.0352L and molarity of solution is 1.66M
The total number of moles of solute present in a given solution per litre is known as its molarity. In contrast to mass, which varies as the system's physical circumstances vary, the volume of a solution changes as a function of changes in the system's physical qualities, such as pressure and temperature. This has an impact on the molality of the solution. The symbol M, sometimes known as a molar, denotes molarity.
[tex]1.66=\frac{n}{0.0352}[/tex]
on solving we get,
n=0.0584 mol
Now, find the number of moles of second solution by the same formula used to find the moles of first solution,
molarity of second solution is 0.892M and total volume is 0.0167L
Now, put the values in the formula,
[tex]0.892=\frac{m}{0.0167}[/tex]
On solving we get,
m=0.0149 mol
and to find the concentration of new solution number of moles is equal to the sum of moles of first solution and second solution.
x=m+n
x=0.0584+0.0149
x=0.0733 mol
Now, molar concentration is,
[tex]M=\frac{x}{V}[/tex]
[tex]M=\frac{0.0733}{0.352+0.0167}[/tex]
On solving we get,
M=1.41[tex]\frac{mol}{L}[/tex]
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Which of the following geometries for the complex ion [Co(en)(H2O)4]2+ are possible?
Check all that apply
O trigonal bipyramidal or square pyramidal
O octahedral
O linear
O tetrahedral or square planar
O trigonal planar
Geometry for the complex ion [Co(en)(H2O)4]2+ that are possible is : Octahedral.
What is octahedral molecular geometry?A compound with six atoms or groups of atoms or ligands grouped symmetrically around a central atom and defining the vertices of the octahedron represents the shape of an octahedron in chemistry and is known as an octahedral molecular geometry (also known as a square bipyramid).
The prefix is octa because the octahedron has eight faces. Octahedral bond angle values between 90° and 180° are what determine the octahedral shape. The angles between each of the four atoms that make up the square bases of the two pyramids of the octahedral structure and one of the apex atoms are both 90 degrees.
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7. Convert 25.0 grams of KMnO4 to moles.
K-39.098
Mn- 54.938
0-15.999
Answer in THREE Sig Figs with Units
What is the relationship between properties and substances?
The relationship between properties and substances is an important one as the properties define or describe the type, kind or composition of a substance. There are two factors that affect the properties of a substance and these are kinetic energies and intermolecular forces.
In chemistry, substances are categorized on the basis of physical and chemical properties. All the substances are composed of tiny particles which are in constant motion due to kinetic energy and keep moving in all directions in a substance.
In addition to this, intermolecular forces are also present in a substance which keeps the particles together. In this way substances maintain their shape, arrangement and properties such as melting point, boiling point, hardness, composition and color due to their particular properties.
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Explain if the process of turning pennies into brass would work on other coins - like a quarter, nickel, or dime.
The process of turning pennies into brass simply has to do with dissolving the copper in the penny by a chemical process and this is then replaced with a brass alloy and this process could theoretically be applied to other coins.
What is a coin?A coin is a tiny, flat, round piece of metal or plastic which is used as legal tender or a medium of exchange. It should be noted that they are mass-produced at a mint so as to facilitate trade, and their weight is standardized.
In order achieve various mechanical, electrical, and chemical properties, it should be noted that copper and zinc can be combined in different ratios in order to create the alloy known as brass.
The composition of other coins, such as quarters, nickels, and dimes, is different from pennies and would require different chemical processes to alter. Additionally, it is illegal to deface or alter U.S. coin currency, so it would not be legal to do this process on any other coin. In this case, it can be applied to other coins.
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How many particles foes 8.0 moles represent?
1 mole of any substance contains 6.023 × 10²³ particles. Therefore, 48.184 particles represents 8.0 moles.
What is mole ?The term mole is defined as the amount of substance in a system which include as many elementary entities as there are atoms present in it. It is denoted by the symbol “mol”. The word mole is coming from the Latin word moles, which means “a mass”.
The mole is also defined as it contain exactly 6.023 × 10²³ elementary entities present in it. 1 mole is exactly equal to the 6.023 × 10²³ elementary entities.
1 mole = 6.023 × 10²³
8 mole = 8 × 6.023 × 10²³
= 48.184 particles
Thus, 1 mole of any substance contains 6.023 × 10²³ particles. Therefore, 48.184 particles represents 8.0 moles.
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What volume of a 0.120 M CaI2 solution would contain 0.078 mol of the solute? A. 35.0 mL O B. 65.0 mL O C. 350 mL O D. 650 mL
650 mL,In order to obtain the volume of solution necessary to provide a given amount of solute in moles, one needs to take the number of moles and divide by the solution concentration in molarity.
Molar concentration, also known as molarity, quantity concentration, or substance concentration, is a unit used to describe the amount of a substance in a solution expressed as a percentage of its volume. The number of moles per liter, denoted by the unit sign mol/L or mol/dm in SI units, is the most often used unit denoting molarity in chemistry. One mol/L of a solution's concentration is referred to as one molar, or 1 M.
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Orange juice has a pH of 4. What is its relative acidity compared to pure water, which has a pH of 7
The relative acidity of orange juice compared to pure water is 1000times. The relationship between acid strength and pH is inverse.
A scale that historically denoted "potential of hydrogen" was used to describe how basic or acidic an aqueous solution was. The pH values of acidic solutions are typically lower than those of basic or alkaline solutions. The pH scale can be used to gauge how strong an acid is. Higher pH values result in weaker acids, while lower pH values result in stronger acids. Therefore, we may conclude that the relationship between acid strength and pH is inverse.
Given the pH of orange juice = 4
Then concentration of orange juice (M1) = 10^-4M
pH of pure water = 7
The concentration of [H+] in water (M2) = 10^-7M
The relative pH = 10^-4/10^-7 = 10^3
Hence its relative acidity compared to pure water is 1000 times.
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Balance the entire chemical reaction using an atom inventory. What is the coefficient for ammonia,
NH3? [?]NH3 + [ ]02 →→ []NO + H₂O
The coefficient of ammonia in the above chemical equation is 3.
What is a balanced equation?A chemical equation is said to be balanced when the number of the atoms involved in the reactants side is equal to the number of atoms in the products side.
Balancing chemical equations involves the addition of stoichiometric coefficients to the reactants and products.
According to this question, ammonia reacts with oxygen gas to produce nitrogen oxide and water as follows:
4NH₃ + 50₂ → 4NO + 6H₂O
Based on the above balanced equation, it can be said that the coefficient of ammonia is 4.
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1. Assertion:Amobea is unicellular organism and has no organs for
breathing.
R: Respiration of amobea is by diffusion.
Answer:
Amoeba has no special respiratory organs and no respiratory pigments but there is a free exchange of gases by diffusion through the general body surface which is permeable to the gases dissolved in water
How many atoms are in 1.4 moles of Cadmium?
Answer:
Answer Below
Explanation:
Answer: 8.4322×1024atoms atoms are in 1.4 moles of cadmium. Cadmium is present in some foods and is emitted when fossil fuels like as coal and oil is used, smoking cigarettes.
Answer:
The answer is 8.4308 × 10²³ atoms
Explanation:
Multiply by Avogadro's number (Nₐ)
Nₐ = 6.022 × 10²³ mol⁻¹
Now,
1.4 × 6.022 × 10²³ = 8.4308 × 10²³
Thus, 8.4308 × 10²³ atoms are in 1.4 moles of Cadmium.
what are the two quantities in this module for which we will develop unit factors to do dimensional analysis with chemical substances?
The two quantities in this module for which we will develop unit factors to do dimensional analysis with chemical substances are mass (usually measured in grams) and volume (usually measured in liters).
Developing Unit Factors for Mass and Volume in Chemical SubstancesUnit factors are developed to convert between two different units of measurement, in this case, mass and volume. We can do this by multiplying the given value by the appropriate unit factor to convert the given value from one unit to the other. For example, if we are given a mass of 10 grams, we can convert this to liters using the unit factor 1 gram = 1 liter. Thus, 10 grams = 10 liters.
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Hydrochloric acid (HCl) is combined with cesium hydroxide (CsOH) in a neutralization reaction. Which ions will combine to form a salt
The ions will combine to form a salt are Cl- and Cs+ when Hydrochloric acid (HCl) is combined with cesium hydroxide (CsOH) in a neutralization reaction.
HCl + CsOH --> CsCl + H2O
Cesium chloride is the salt that results from the neutralization of hydrochloric acid with cesium hydroxide. Because both of the bonds in salt compounds the positively charged cesium ion and the negatively charged chloride ion have electrical charges, they are referred to as ionic bonds. A neutralization reaction occurs when an acid and a base combine to form salt and water in an aqueous solution. A salt is the name for the aqueous cesium chloride that is created during the process.
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why was the bohr model replaced
To solve this we must be knowing each and every concept related to atom. Therefore, Bohr's model was abandoned since it lacked explanatory, descriptive, and predictive ability.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. Bohr's model was abandoned in favor of the quantum mechanical model since it lacked explanatory, descriptive, and predictive ability.
Therefore, Bohr's model was abandoned since it lacked explanatory, descriptive, and predictive ability.
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Please help : ) and please explain in answer
The transfer of energy doe not always affect the appearance of the lake because it can attain a form that is quite similar to the other. It can be because of conduction, convection, and radiation.
What are the processes of heat transference?Heat transference can be described as a natural phenomenon that can be caused by conduction, convection, or radiation.
Convection can be defined as the transfer of energy in a given fluid such as, in this case, water. The energy transfer is due to particular molecular motion, energy is transferred by bulk, or macroscopic, the motion of the fluid.
Radiation can be defined as heat transfer through space due to electromagnetic radiation. Conduction can be defined as the transfer of energy between molecules due to direct contact.
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How do we measure energy of a reaction?
Answer:
joules.
Explanation:
A measure of the total internal heat content.
which could be exothermic or endothermic
A 211-mL sample of a 0.285 M CaCl2 solution is left on a hot plate overnight; the following morning, the solution is 1.25 M. What volume of water evaporated from the 0.285 M CaCl2 solution
When a 211-mL sample of a 0.285 M CaCl₂ solution is left on a hot plate overnight and the following morning, the solution is 1.25 M, the volume of water evaporated from the 0.285 M CaCl₂ solution is 48.108 ml.
Molarity (M) is defined as the ratio of the number of moles of solute present in a solution to the volume of the solution in litres.
given here,
Molarity of the original solution(M₁) = 0.285M
Volume of the original solution(V₁) = 211 ml
Molarity of the solution in the morning (M₂) = 1.25 M
Volume of the solution in the morning (V₂) = ?
We will calculate the volume of the solution in the morning by using the formula:
M₁ × V₁ = M₂ × V₂
⇒0.285 M× 211 ml = 1.25 M × V₂
⇒V₂ = 0.285 M× 211 ml / 1.25 M
⇒V₂= 48.108ml
The volume of water evaporated from the 0.285M CaCl₂ solution is 48.108 ml.
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How many moles is 20 grams?
0.5 moles are present in 20 grams of calcium.
The mole, which is denoted by the symbol "mol," is the volume of a system that includes as many elementary particles as there are atoms in 0.012 kilograms of carbon 12.
The number of atoms, molecules, or ions that make up one mole of a substance is 6.022 × 10²³ . The term "Avogadro's number" or "Avogadro's constant" refers to the number 6.022 × 10²³
Atomic Mass of Calcium = 40u
(Atomic Mass is same as Molar Mass, so)
Molar Mass of Calcium = 40g
Formula to find number of moles
Number of Moles = given mass / molar mass
= 20 / 40 = 0.5 moles
Therefore, 0.5 moles are present in 20 grams of calcium.
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The complete question is
How many moles are there in 20 g of calcium