Answer:
After 47.9 days, will remain 14.5mg of the isotope
Explanation:
The radioactive decay follows always first-order kinetics where its general law is:
Ln[A] = -Kt + ln[A]₀
Where [A] is actual concentration of the atom, k is rate constant, t is time and [A]₀ is initial concentration.
We can find rate constant from half-life as follows:
[tex]t_{1/2} = \frac{ln2}{K}[/tex]
K = ln 2 / 27.7 days
K = 0.025 days⁻¹
Replacing, initial amount of isotope is 48.0mg = [A]₀ , K is 0.025 days⁻¹ and t = 47.9 days:
Ln[A] = -Kt + ln[A]₀
Ln[A] = -0.025 days⁻¹*47.9 days + ln (48.0mg)
ln [A] = 2.6726
[A] = e^ (2.6726)
[A] = 14.5mg
After 47.9 days, will remain 14.5mg of the isotope
Question 9 of 10
Which statement correctly describes magnetic field lines?
O A. They cross each other at right angles.
B. They always point away from a south pole.
C. They show the direction a south pole will point.
D. They join north pole to south pole..
11.
What is the value of AH in k cal/mol for the following reaction?
CH3CH2CH3 + Br2
CH3 -CH-CH3 + HBr
Br
(1)
-12
(2)
-13
(3)
-15
(
4)
-16
Answer:
(1) -12 Kcal/mol
Explanation:
Our answer options for this question are:
(1) -12 Kcal/mol
(2) -13 Kcal/mol
(3) -15 Kcal/mol
(4) -16 Kcal/mol
With this in mind, we can start with the chemical reaction (Figure 1). In this reaction, two bonds are broken, a C-H and a Br-Br. Additionally, a C-Br and a H-Br are formed.
If we want to calculate the enthalpy value, we can use the equation:
ΔH=ΔHbonds broken-ΔHbonds formed
If we use the energy values reported, its possible to calculate the energy for each set of bonds:
ΔHbonds broken
C-H = 94.5 Kcal/mol
Br-Br = 51.5 Kcal/mol
Therefore:
105 Kcal/mol + 53.5 Kcal/mol = 146 Kcal/mol
ΔHbonds formed
C-Br = 70.5 Kcal/mol
H-Br = 87.5 Kcal/mol
Therefore:
70.5 Kcal/mol + 87.5 Kcal/mol = 158 Kcal/mol
ΔH of reaction
ΔH=ΔHbonds broken-ΔHbonds formed=(146-158) Kcal/mol = -12 Kcal/mol
I hope it helps!
How does distance between two objects affect their gravitational force? (2 points)
a
Force increases as distance increases.
b
Force decreases as distance increases.
c
Force decreases as distance decreases.
d
Force is not related to distance.
Answer:
Option B: as the distance between the objects increases the Force of gravity decreases
At a certain temperature the equilibrium constant, Kc, equals 0.110 for the reaction: 2 ICl (g) ⇌ I2 (g) +Cl2 (g) What is the equilibrium concentration of ICl if 0.750 mol of I2 and 0.750 mol of Cl2 are initially mixed in a 1.00-L flask?
Answer:
The equilibrium concentration of ICl is 2.26 M
Explanation:
Chemical equilibrium is a state in which no changes are observed as time passes, despite the fact that the substances present continue to react. This is because chemical equilibrium is established when the forward and reverse reaction take place simultaneously at the same rate.
For the study of chemical equilibrium, the so-called equilibrium constant Kc is useful. Being:
aA + bB ⇔ cC + dD
the equilibrium constant Kc is:
[tex]Kc=\frac{[C]^{c} *[D]^{d} }{[A]^{a}*[B]^{b} }[/tex]
That is, the constant Kc is equal to the multiplication of the concentrations of the products raised to their stoichiometric coefficients by the multiplication of the concentrations of the reactants also raised to their stoichiometric coefficients.
For the reaction:
2 ICl (g) ⇌ I₂ (g) +Cl₂ (g)
the constant Kc is:
[tex]Kc=\frac{[I_{2} ]*[Cl_{2} ]}{[ICl]^{2} }[/tex]
Being Kc =0.110 and the concentration being the amount of moles of solute that appear dissolved in each liter of the mixture and being calculated by dividing the moles of the solute by the liters of the solution:
[tex][I_{2} ]=\frac{0.750 moles}{1 L} =0.750 \frac{moles}{L}[/tex][tex][Cl_{2} ]=\frac{0.750 moles}{1 L} =0.750 \frac{moles}{L}[/tex]and replacing in the constant we get:
[tex]0.110=\frac{0.750*0.750}{[ICl]^{2} }[/tex]
Solving, you get the ICl concentration at equilibrium:
[tex][ICl]^{2} =\frac{0.750*0.750}{0.110 }[/tex]
[tex][ICl] =\sqrt{\frac{0.750*0.750}{0.110 }}[/tex]
[ICl]= 2.26 M
The equilibrium concentration of ICl is 2.26 M
What ion will be formed by the phosphorus atom shown below when it has a stable set of valence electrons?
Phosphorus ion have 3 extra electrons which create a valence of -3.
The correct answer is P3-
Ions combine with other elements and combination in one atom of phosphorus with four atoms of oxygen will create phosphorus ion PO4^3- .
Phosphorus atom has to render 3s electrons to oxygen atom of phosphoryl group.
Phosphorus become positively charged and oxygen becomes negatively charged.
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An 80L capacity steel cylinder contains H2 at a pressure of 110 atm and 30 ° C, after extracting a certain amount of gas, the pressure is 80 atm at the same temperature. How many liters of hydrogen (measured under normal conditions) have been extracted?
Answer:
2200 L
Explanation:
Ideal gas law:
PV = nRT,
where P is absolute pressure,
V is volume,
n is number of moles,
R is universal gas constant,
and T is absolute temperature.
The initial number of moles is:
(110 atm) (80 L) = n (0.0821 L atm / K / mol) (30 + 273.15) K
n = 353.58 mol
After some gas is removed, the number of moles remaining is:
(80 atm) (80 L) = n (0.0821 L atm / K / mol) (30 + 273.15) K
n = 257.15 mol
The amount of gas removed is therefore:
n = 353.58 mol − 257.15 mol
n = 92.43 mol
At normal conditions, the volume of this gas is:
PV = nRT
(1 atm) V = (92.43 mol) (0.0821 L atm / K / mol) (273.15 K)
V = 2162.5 L
Rounded, the volume is approximately 2200 liters.
Write a balanced nuclear equation for the following: The nuclide thorium-234 undergoes beta decay to form protactinium-234 .
Answer:
²³⁴₉₀Th --> ²³⁴₉₁Pa + ⁰₋₁e
Explanation:
thorium-234 = ²³⁴₉₀Th
beta decay = ⁰₋₁e
protactinium-234 = ²³⁴₉₁Pa
The balanced nuclear equation is given as;
²³⁴₉₀Th --> ²³⁴₉₁Pa + ⁰₋₁e
Help please due today
Answer:
It is a becaues i am a doctor and i know about that
Explanation:Just here to help
what volume will it occupied 40 degrees celsius a gas sample was collected when a temperature is 27 degrees celsius and the volume of 1 L
Using Charles law
[tex]\boxed{\sf \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}}[/tex]
[tex]\\ \sf\longmapsto V_1T_2=V_2T_1[/tex]
[tex]\\ \sf\longmapsto 1(40)=27V_2[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{40}{27}[/tex]
[tex]\\ \sf\longmapsto V_2=1.48\ell[/tex]
a sample of gas occupies a volume of 2.62 liters at 25 C and 1.00 atm. what will be the volume at 50 C and 2 atm
Answer:2.62 L
Explanation:
A sample of gas occupies a volume of 2.62 liters at 25° C and 1.00 atm. and the volume at 50° C and 2 atm then volume is 2.62 liters.
What is ideal gas law ?The equation of state for a fictitious perfect gas is known as the ideal gas law, sometimes known as the generic gas equation. Although it has significant drawbacks, it is a decent approximation of the behavior of many gases under various situations.
An ideal gas is one in which there are no intermolecular attraction forces and all collisions between atoms or molecules are entirely elastic. It may be seen as a group of perfectly hard spheres that collide but do not else interact with one another.
By using ideal gas equation,
P₁ V ₁ ÷ T = P₂V₂ ÷ T
1 × 2.62 ÷ 25 = 2 × V₂ ÷ 50
V₂ = 1 × 2.62 × 50 ÷ 25 × 2
V₂ = 2.62 liters.
Thus, a sample of gas occupies a volume of 2.62 liters at 25° C and 1.00 atm. and the volume at 50° C and 2 atm then volume is 2.62 liters.
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To refine aluminum from its ore, aluminum oxide is electrolyzed to form aluminum and oxygen. At which electrode does oxygen form? options: A) Both the anode and the cathode B) Cathode C) Neither electrode D) Anode
Answer:
im pretty sure its the anode
Explanation:
To solve such, we must know the concept of electrolysis reaction. The correct option is option D among all given options. At anode electrode oxygen forms.
What is chemical reaction?Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.
Electrolysis is the process of passing an electric current through a material to cause a chemical change. A chemical change occurs when a material loses or acquires the electron. To refine aluminum from its ore, aluminum oxide is electrolyzed to form aluminum and oxygen. At anode electrode oxygen forms.
Therefore, the correct option is option D among all given options. At anode electrode oxygen forms.
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What element is being reduced in the following redox reaction? MnO4-(aq) + H2C2O4(aq) → Mn2+(aq) + CO2(g) What element is being reduced in the following redox reaction? MnO4-(aq) + H2C2O4(aq) → Mn2+(aq) + CO2(g) H O Mn C
Answer: Mn is getting reduced.
Explanation:
Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.
Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.
[tex]MnO_4^-(aq)+H_2C_2O_4(aq)\rightarrow Mn^{2+}(aq)+CO_2(g)[/tex]
Oxidation : As Manganese has an oxidation state of +7 in [tex]MnO_4^-[/tex] and +2 in [tex]Mn^{2+}[/tex], the oxidation state is decreasing and hence it is getting reduced.
Reduction : As carbon has an oxidation state of +3 in [tex]H_2C_2O_4[/tex] and +4 in [tex]CO_2[/tex], the oxidation state is increasing and hence it is getting oxidized.
The element which is reduced in the redox reaction is Mn.
The redox reaction is shown below:
MnO₄⁻(aq) + H₂C₂O₄(aq) → Mn²⁺(aq) + CO₂(g)
A redox reaction is the type of reaction which involves oxidation processes
occurring with a corresponding reduction process.
Oxidation reaction involves the reaction in which a substance loses its
electrons to become positively charged with an increase in the oxidation
state.
Reduction reaction is defined as the reaction in which a substance gains
electrons to become positively charged with a decrease in the oxidation
state.
MnO₄⁻ has an oxidation state of +7 and Mn²⁺ having an oxidation state of +2
signifies a decrease in the oxidation state.
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Fill in the blanks with the words given below- [Atoms, homogeneous, metals, true, saturated, homogeneous, colloidal, compounds, lustrous] 1.An element which are sonorous are called................ 2.An element is made up of only one kind of .................... 3.Alloys are ............................. mixtures. 4.Elements chemically combines in fixed proportion to form ........................ 5. Metals are................................... and can be polished. 6. a solution in which no more solute can be dissolved is called a .................... solution. 7. Milk is a .............. solution but vinegar is a .................. solution. 8. A solution is a ................... mixture. pls help, could not get these answers
Answer:
1. metals
2. atom
3. homogeneous
4. compounds
5. lustrous
6. saturated
7. colloidal
8. homogeneous
Explanation:
1. Consider the following thermochemical reaction for kerosene:
2 C12H26(l) + 37 O2(g) 24 CO2(g) + 26 H2O(l) + 15,026 kJ
(a) When 21.3 g of CO2 are made, how much heat is released?
(b) If 500.00 kJ of heat are released by the reaction, how grams of C12H26 must have been consumed ?
(c) If this reaction were being used to generate heat, how many grams of C12H26 would have to be reacted to generate
enough heat to raise the temperature of 750g of liquid water from 10oC to 90oC?
2. Consider the reaction: NaNO3(s) + H2SO4(l) → NaHSO4(s) + HNO3(g) ΔH° = 21.2 kJ
How much heat must absorbed by the reaction system to convert 100g of NaNO3 into NaHSO4(s)?
3. What is the enthalpy change when 49.4 mL of 0.430 M sulfuric acid reacts with 23.3 mL of 0.309 M potassium
hydroxide?
3.
H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(l) ΔH° = –111.6 kJ/mol
do you have the specific heat for part 2?
The ΔHvap of nitrous oxide is 16.53 kJ · mol−1 and its ΔSvap is 89.51 J · mol−1 · K−1. What it the boiling point of nitrous oxide?
Answer:
[tex]T_b=-88.48\°C[/tex]
Explanation:
Hello,
In this case, since the entropy of vaporization is defined in terms of the enthalpy of vaporization and the boiling point of the given substance, nitrous oxide, as shown below:
[tex]\Delta _{vap}S=\frac{\Delta _{vap}}{T_b}[/tex]
Solving for the boiling point of nitrous oxide, we obtain:
[tex]T_b=\frac{\Delta _{vap}H}{\Delta _{vap}S}=\frac{16.53\frac{kJ}{mol}*\frac{1000J}{1kJ} }{89.51\frac{J}{mol} } \\ \\T_b=184.67K[/tex]
Which in degree Celsius is also:
[tex]Tb=184.67-273.15\\\\T_b=-88.48\°C[/tex]
Best regards.
the following glassware was found in a lab drawer: 12 beakers, 10 flasks and 60 test tubes. what percent of the glassware are test tubes?
Answer:
73.1707317073%
=> Approximately 73.2%
Explanation:
Total = 60 + 10 + 12
=> 82
Test tubes are 60/82
=> 30/41
=> 73.1707317073%
=> Approximately 73.2%
Answer:
73.17%
Explanation:
To find the percentage of test tubes to the overall glassware, we need to get the number of test tubes divided by the total number of glassware.
12 beakers + 10 flasks + 60 test tubes = 82 glassware
% test tube = 60 / 82 = .7317 ==> 73.17 %
So 73.17 % of the glassware was test tubes.
Cheers.
A certain covalent compound is named sulfur hexafluoride. What's the chemical formula for this compound? A. F6S2 B. F6S C. S2F6 D. SF6
Answer: The sulphur hexafluoride will have a chemical formula of [tex]SF_6[/tex]
Explanation:
A covalent compound is a compound where the sharing of electrons takes place between two elements which are non-metals.
The naming of covalent compound is given by:
1. The less electronegative element is written first.
2. The more electronegative element is written second. Then a suffix is added with it. The suffix added is '-ide'.
3. If atoms of an element is greater than 1, then prefixes are added which are 'mono' for 1 atom, 'di' for 2 atoms, 'tri' for 3 atoms and so on.
Thus sulphur hexafluoride will have a chemical formula of [tex]SF_6[/tex]
Answer:
D. sf6
Explanation:
If sulfur gained another electron, would its charge be positive or negative?
Explain your thinking. *
Answer:
AS WE KNOW THAT , when non-metallic elements gain electrons to form anions, SO sulphur is non metal and have the capacity to gain two electrons as lies in 6th group so it can gain electron and become sulphide ion(S-).
Thanks for asking questionExplanation:
Find the pH of these buffer solutions using the information provided: 1L solution containing 80g of lactic acid (MW
Answer:
pH of the solution is 2.0
Explanation:
The lactic acid is a weak acid that is in equilibrium with water as follows:
Lactic acid + H2O ⇄ Lactate + H₃O⁺
And Ka for lactic acid: 1.38x10⁻⁴
Ka = 1.38x10⁻⁴ = [Lactate] [H₃O⁺] / [Lactic acid]
Initial concentration of lactic acid is (MW: 112.06g/mol):
80g * (1mol / 112.06g) / 1L = 0.714M
The equilibrium concentration of the species in the equilibrium are:
[Lactate] = X
[H₃O⁺] = X
[Lactic acid] = 0.714-X
Replacing in Ka expression:
1.38x10⁻⁴ = [X] [X] / [0.714-X]
9.8532x10⁻⁵ - 1.38x10⁻⁴X = X²
9.8532x10⁻⁵ - 1.38x10⁻⁴X - X² = 0
Solving for X:
X = -1.0x10⁻². False solution, there is no negative concentrations
X = 9.86x10⁻³M. Right solution.
As [H₃O⁺] = X
[H₃O⁺] = 9.86x10⁻³M
and pH = -log [H₃O⁺] = -log 9.86x10⁻³M
pH = 2.0
pH of the solution is 2.0HELP! A man makes breakfast. He puts some toast in the toaster, and mixes some eggs with a little milk in a bowl. As he begins cooking the eggs, he smells the toast burning. He takes the toast out of the toaster and puts some butter on it, which melts. Finally, he pours some orange juice through a strainer to remove the pulp. He eats the meal, and he digests it as he drives to work in his car.
A. Which option correctly identifies a chemical and a physical change in the scenario?
B. Burning toast is a chemical change; straining orange juice is a physical change.
C. Digesting food is a physical change; the car burning gas is a chemical change.
D. Burning toast is a physical change; straining orange juice is a chemical change.
Digesting food is a chemical change; the car burning gas is a physical change.
Answer:B. Burning toast is a chemical change; straining orange juice is a physical change.
Explanation:
A Physical change Is a type of change on a substance that does not affect its composition but can only change the appearance of the substance.
While
A Chemical changes is one that changes the substance to an entirely new substance.
Now 1. Burning toast is a chemical change, This is because First, Burning is a chemical reaction on its own . The toast also is a different substance from the white bread itself to a brown substance .
2. Straining orange juice is a physical change because no new substance is being formed only a SEPARATION of the orange pulp from the juice.
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We have that Burning toast is a chemical change; straining orange juice is a physical change.
The correct option is Option B
Physical change
This Refers to a change to the Physical Characteristics of a substance
While
Chemical change is a change Chemical Characteristics of a substance
and
Physical changes tends to undergo reversible processes while
chemicals do not
Therefore
The correct option is Option B
Burning toast is a chemical change; straining orange juice is a physical change.
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what type of forces either interatomic or intermolecular forces prevents ice cubes from adopting the shape of their container
There are two types of electrostatic forces: interatomic or intermolecular.
In this case the type of force that prevents ice cubes from adopting the shape of their container is intermolecular.
Interatomic forcesWithin a molecule, the atoms are held together by interatomic forces. These forces are what determine the chemical properties of substances because it is these forces that must be overcome for a chemical change to occur.
In summary, intermolecular forces are characterized by holding more than one molecule together.
Intermolecular forcesOn the other side, intermolecular forces act on different molecules or ions and cause them to attract or repel each other, causing different physical states in chemical compounds.
Therefore, the intermolecular forces are responsible for the existence of the liquid and solid state (between the molecules of a gas do not exist intermolecular forces.).
Case of ice cubesThen ice cubes do not ocuppy the shape of thir container because it is in solid state, existing intermolecular force between molecules to maintain said physical state.
In summary, the type of force that prevents ice cubes from adopting the shape of their container is intermolecular.
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https://brainly.com/question/14220340?referrer=searchResultshttps://brainly.com/question/13136165?referrer=searchResultsA chamber contains equal molar amounts of He, Ne, Ar, and Kr. If the total chamber pressure is 1 atm, then the partial pressure (in atm) of Kr is:
Answer:
The correct answer is 0.25 atm.
Explanation:
As mentioned in the given question that the chamber comprises equal molar concentrations of He, Ne, Ar and Kr gas. So, let us assume that the moles of all the gases will be x then the total number of moles will be 4x.
The formula for calculating mole fraction is,
Mole fraction = mole of the substance/total moles
The mole fraction of Kr = x/4x = 0.25
The total pressure given in the chamber is 1 atm. Therefore, the partial pressure will be,
Partial pressure = mole fraction * Total pressure
Partial pressure = 0.25 * 1 = 0.25 atm.
The partial pressure of Kr is 0.25 atm.
We are told that there is an equal molar amounts of He, Ne, Ar, and Kr. If we decide to say, let the molar amount of each gas be x, the total number of moles of all the gases will now be; x + x+ x + x = 4x
Let us recall that partial pressure of a gas can be obtained form the formula;
Partial pressure = mole fraction × total pressure
Mole fraction of Kr = x/4x = 1/4
Total pressure = 1 atm
Partial pressure of Kr = 1/4 × 1 = 0.25 atm
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g When considering the effects of temperature on spontaneity, if both ΔH and ΔS are positive, _______. Select the correct answer below: the process is spontaneous at all temperatures
Explanation:
The spontaneity of a system is deduced by the sign of the gibbs free energy value. If it is negative, it means the process / reaction is spontaneous however a positive value indicates the such process is not spontaneous.
Gibbs free energy, enthalpy and entropy are related by the following equation;
ΔG = ΔH - TΔS
A positive value of enthalpy, H and entropy, S means that G would always be a negative value at all temperatures.
Arrange the following substances in the order of increasing entropy at 25°C. HF(g), NaF(s), SiF 4(g), SiH 4(g), Al(s) lowest → highest
Answer:
Al(s)<NaF(s)<HF(g)<SiH4(g)<SiF4(g)
Explanation:
Hello,
In this case, we can arrange the increasing order of entropy at 25 \°C by taking into account, at first, that since solids are more molecularly organized than gases, the first we have solid sodium fluoride and solid aluminium, but in this case, as the higher the molar mass, the higher the entropy, the molar mass of aluminium is 27 g/mol and 42 g/mol for sodium fluoride, therefore, we first have:
Al(s)<NaF(s)
Afterwards, since the molar mass of hydrogen fluoride (HF), silicon fluoride (SiF4) and silane (SiH4) are 20, 104 and 32 g/mol respctively, since silicon fluoride has the greater molar mass, it also has the higher entropy. In such a way, the overall order turns out:
Al(s)<NaF(s)<HF(g)<SiH4(g)<SiF4(g)
Best regards.
Aqueous ammonia is added to a mixture of silver chloride and water. Given that Kf for the reaction between Ag+ and NH3 is large, which of the following are true?
A) The free ions are favored over the complex ion.
B) The complex ion is favored over solid silver chloride.
C) The free Ag+ ion is unstable.
D) More silver chloride will precipitate.
Answer:
B) The complex ion is favored over solid silver chloride
C) The free Ag+ ion is unstable.
Explanation:
Hello,
In this case, since the dissociation of solid silver chloride occurs at equilibrium with a neglectable solubility product (very small Ksp), which means that the solid tends to remain undissolved:
[tex]AgCl(s)\rightleftharpoons Ag^+(aq)+Cl^-(aq)[/tex]
By the addition of ammonia, the following reaction is favored:
[tex]Ag^+(aq)+2NH_3(aq)\rightleftharpoons [Ag(NH_3)_2]^+(aq)[/tex]
Which has a large equilibrium constant, which means that the formation of the complex is assured. In such a way, by addition of more ammonia, more complex will be formed, therefore B) The complex ion is favored over solid silver chloride is true. Moreover, C) The free Ag+ ion is unstable, since they tend to form the complex once they are formed by the solid silver chloride so it readily reacts.
Best regards.
The Halogen Group is also known as the?
salt formers
acid makers
Answer:
I think b acid makers
Explanation:
hope it will help you
Divers often inflate heavy duty balloons attached to salvage items on the sea floor. If a balloon is filled to a volume of 1.20 L at a pressure of 6.25 atm, what is the volume of the balloon when it reaches the surface?
Answer:
7.50 L
Explanation:
The balloon has a volume of 1.20 L (V₁) when the pressure at the sea floor is 6.25 atm (P₁). When it reaches the surface, the pressure is that of the atmosphere, that is, 1.00 atm (P₂). If we consider the gas to behave as an ideal gas and the temperature to be constant, we can calculate the final volume (V₂) using Boyle's law.
P₁ × V₁ = P₂ × V₂
V₂ = P₁ × V₁ / P₂
V₂ = 6.25 atm × 1.20 L / 1.00 atm
V₂ = 7.50 L
A scientist observes that the electrical resistance of a superconducting material drops to zero when the material is cooled to very low temperatures. Which of the following statements best describes what the scientist is observing?
The scientist is observing the electrical power of a superconductor.
The scientist is observing the temperature of a superconductor.
The scientist is observing an intensive property of a superconductor.
The scientist is observing an extensive property of a superconductor
Answer:
The scientist is observing an intensive property of a superconductor.
Explanation:
An intensive property is a bulk property of matter. This means that an intensive property does not depend on the amount of substance present in the material under study. Typical examples of intensive properties include; conductivity, resistivity, density, hardness, etc.
An extensive property is a property that depends on the amount of substance present in a sample. Extensive properties depend on the quantity of matter present in the sample under study. Examples of extensive properties include, mass and volume.
Resistance of a superconducting material has nothing to do with the amount of the material present hence it is an intensive property of the superconductor.
Answer:
The scientist is observing an intensive property of a superconductor.
Explanation:
its the only one that makes logical sense
Calculate the number of iron atoms contained in 434.52 g of iron: Question 7 options: 2.620 x 10 26 Fe atoms 5.769 x 10 24 Fe atoms 4.685 x 10 24 Fe atoms 3.223 x 10 25 Fe atoms 1.169 x 10 23 Fe atoms
Answer:
[tex]\boxed {\boxed {\sf 4.685 \times 10^{24} \ Fe \ atoms}}[/tex]
Explanation:
We are asked to convert grams of iron to atoms of iron.
1. Convert Grams to MolesFirst, we convert grams to moles. We use the molar mass or the mass in 1 mole of a substance. This is found on the Periodic Table because the molar mass is equal to the atomic mass, but the units are grams per mole instead of atomic mass units. Look up iron's molar mass.
Fe: 55.84 g/molWe convert using dimensional analysis, so we must set up a ratio using the molar mass.
[tex]\frac {55.84 \ g \ Fe}{ 1 \ mol \ Fe}[/tex]
We are converting 434.52 grams to moles, so we multiply by this value.
[tex]434.52 \ g \ Fe *\frac {55.84 \ g \ Fe}{ 1 \ mol \ Fe}[/tex]
Flip the ratio so the units of grams of iron cancel.
[tex]434.52 \ g \ Fe *\frac { 1 \ mol \ Fe}{55.84 \ g \ Fe}[/tex]
[tex]434.52 *\frac { 1 \ mol \ Fe}{55.84}[/tex]
[tex]\frac { 434.52}{55.84} \ mol \ Fe[/tex]
[tex]7.781518625 \ mol \ Fe[/tex]
2. Convert Moles to AtomsNext, we convert moles to atoms. We use Avogadro's Number or 6.02 ×10²³. It is the number of particles (atoms, molecules, formula units, etc) in 1 mole of a substance. For this problem, the particles are atoms of iron. We set up another ratio using this number.
[tex]\frac {6.02 \times 10^{23} \ atoms \ Fe }{ 1 \ mol \ Fe}[/tex]
Multiply by the number of moles we calculated.
[tex]7.781518625 \ mol \ Fe *\frac {6.02 \times 10^{23} \ atoms \ Fe }{ 1 \ mol \ Fe}[/tex]
The units of moles of iron cancel.
[tex]7.781518625 *\frac {6.02 \times 10^{23} \ atoms \ Fe }{ 1 }[/tex]
[tex]4.68447421 \times 10^{24} \ atoms \ Fe[/tex]
The correct answer choice is Choice 3: 4.685 × 10²⁴ atoms of iron.
Which describes the molecule below
Answer:
Option D. A lipid with three unsaturated fatty acid.
Explanation:
The molecule in the diagram above contains three fatty acid.
A careful observation of the molecule reveals that each of the three fatty acids contains a double bond.
The presence of a double bond in a compound shows that the compound is unsaturated.
Thus, we can say that the molecule is a lipid with three unsaturated fatty acid.