Answer: D. The Government could take away research funds if ethical standards are not met
The government enforce ethical standards of scientific experiments
B. The government could take away research funds if ethical
standards are not met.
Ethical standards are a set of principles established by the founders of the organization to communicate its underlying moral values. This code provides a framework that can be used as a reference for decision making processes.
How does the government control scientific research?Politicians and bureaucrats control scientific research and research outcomes by selectively funding projects that look for potential disasters, ideally global disasters.
What are the 8 ethical standards?This analysis focuses on whether and how the statements in these eight codes specify core moral norms (Autonomy, Beneficence, Non-Maleficence, and Justice), core behavioral norms (Veracity, Privacy, Confidentiality, and Fidelity), and other norms that are empirically derived from the code statements.
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One compound in the list below is a gas at room conditions, while all of the others are liquids or solids. For each compound, indicate whether it is the gas or the force most responsible for it being a liquid or solid.
First list:
A. CH3OH
1. a gas2. dispersion forces 3. dipolar forces4. hydrogen bonds5. ionic bonds6. covalent bondsB. CH4
1. a gas2. dispersion forces 3. dipolar forces4. hydrogen bonds5. ionic bonds6. covalent bondsC. CaCO3
1. a gas2. dispersion forces 3. dipolar forces4. hydrogen bonds5. ionic bonds6. covalent bondsD. C6H14
1. a gas2. dispersion forces 3. dipolar forces4. hydrogen bonds5. ionic bonds6. covalent bondsSecond list:
A. H2O
B. C2H2
C. CCl4
D. KCl
Answer:
First list
A. CH3OH----hydrogen bonds
CH4----dispersion forces
CaCO3---ionic bonds
C6H14----dispersion forces
Second list
H2O------ liquid----hydrogen bonds
C2H2----gas---dispersion forces
CCl4---liquid---dispersion forces
KCl----solid---ionic bonds
Explanation:
For every compound, the intermolecular forces decide whether the substance will be solid liquid or gas. Molecules are known to associate with each other in any particular state of matter. These molecules are held together by different intermolecular interactions with varying degrees of strength. The strength of the intermolecular interaction between the molecules of a substance will decide if the substance will be a solid, liquid or gas.
When the intermolecular forces are very strong such as in ionic solids and covalent network solids, the substance exists as a solid. When the intermolecular forces are not so strong such as dispersion forces and hydrogen bonds, the substance exists as a liquid. However, very weak intermolecular dispersion forces are found in gases hence the molecules are relatively free when compared to molecules of liquids and solids.
ultraviolet photon (λ = 58.4nm) from a helium gas discharge tube is absorbed by a hydrogen molecule which is at rest. Since momentum is conserved, what is the velocity of the hydrogen molecule after absorbing the photon? What is the translational energy of the hydrogen molecule in Jmol-1.
[h = 6.626 x 10-34 Js; NA = 6.022 x 1023 mol-1]
Answer:
Translation energy of 1 mole of H2 molecules = KE x Avogadros number
[tex]= 1.923 * 10^{-26} * 6.022 * 10^{23}\\\\= 0.0116 J \\\\= 1.16 * 10^{-2} \ J[/tex]
Explanation:
Photon wavelength [tex]= 58.4 nm = 58.4 * 10^{-9} m[/tex]
Photon momentum = h/wavelength
[tex]= (6.626 * 10^{-34})/(58.4 * 10^{-9})\\\\ = 1.1346 * 10^{-26} \ kg.m/s[/tex]
Mass of H2 molecule m = molar mass/Avogadros number
[tex]= (2.016)/(6.022 * 10^{23})\\\\= 3.3477 * 10^{-24} \ g = 3.3477 * 10^{-27} \ kg[/tex]
Since momentum is conserved:
Photon momentum = H2 molecule momentum = mass x velocity of H2
[tex]1.1346 * 10^{-26} = 3.3477 * 10^{-27} * v[/tex]
velocity [tex]v = 3.389 m/s = 3.39 m/s[/tex]
Translation energy of 1 H2 molecule = kinectic energy (KE) = (1/2)mv^2
[tex]= 1/2 * 3.3477 * 10^{-27} * 3.389^2\\\\= 1.923 * 10^{-26} J[/tex]
Translation energy of 1 mole of H2 molecules = KE x Avogadros number
[tex]= 1.923 * 10^{-26} * 6.022 * 10^{23}\\\\= 0.0116 J \\\\= 1.16 * 10^{-2} \ J[/tex]
Calculate the percent saturated fat in the total fat in butter
The cryosphere is part of which sphere of the Earth system?
atmosphere
biosphere
geosphere
hydrosphere
Answer:
Ice (frozen water) is part of the hydrosphere, but it's given its own name, the cryosphere.
The cryosphere is part of the hydrosphere of the Earth system. The correct option is D.
What is the cryosphere?The cryosphere contains all the frozen parts of the earth. The term is made up of the Greek word “krios” which means cold. All the frozen water of the oceans and snow comes under the cryosphere.
The atmosphere contains all spheres, it is an envelope of gases. The geosphere is the land part of the earth, and the biosphere is the part where the living part is present.
The cryosphere is h habitat of many living creatures, and the climate of the earth is highly dependent on this sphere. The warmth of the earth is increasing and the cryosphere part is decreasing day by day, which is having problems for many animals.
Thus, the correct option is D, hydrosphere.
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What allows two or more atoms to be held together?
Answer:
Atoms come together to form molecules because of their electrons. Electrons can join (or bond) atoms together in two main ways. When two atoms share electrons between them, they are locked together (bonded) by that sharing. These are called covalent bonds.
Explanation:
Answer:
Electrons
Explanation:
took the test got 100%
Of the following three atoms, one tends to lose three electrons, another tends to lose two electrons, and another tends to lose one electron. Rank these atoms in order of the number of electrons they tend to lose, from most to fewest: potassium, K; calcium, Ca; gallium, Ga. Rank from most to fewest.
Answer: Ga > Ca > K
Explanation:
Electronic configuration represents the total number of electrons that a neutral element contains. We add all the superscripts to know the number of electrons in an atom.
The electrons are filled according to Afbau's rule in order of increasing energies. The metals tend to get stable by losing electrons to attain noble gas configuration.
[tex]K:19:1s^22s^22p^63s^23p^64s^1[/tex]
[tex]K^+:18:1s^22s^22p^63s^23p^6[/tex]
[tex]Ca:20:1s^22s^22p^63s^23p^64s^2[/tex]
[tex]Ca^{2+}:18:1s^22s^22p^63s^23p^6[/tex]
[tex]Ga:31:1s^22s^22p^63s^23p^64s^23d^{10}4s^24p^1[/tex]
[tex]Ga^{3+}:28:1s^22s^22p^63s^23p^64s^23d^{10}[/tex]
Thus gallium (Ga) loses three electrons, Calcium (Ca) loses 2 electrons and Potassium (K) loses one electron.
According to the ideal gas law, what happens to the volume of a gas when the
temperature doubles (all else held constant)?
A. The volume stays constant.
B. The volume doubles.
OOO
C. It cannot be determined
D. The volume is halved
According to the ideal gas law, when the temperature of a gas doubles, its volume doubles as well (Option B).
What does the ideal law state?The ideal gas law relates the pressure, volume, number of moles and temperature of an ideal gas.
Let's consider the equation of the ideal gas law.
P . V = n . R .T
V = n . R . T / P
As we can see, there is a direct relationship between the volume and the temperature. Thus, if the temperature doubles, the volume will double as well.
According to the ideal gas law, when the temperature of a gas doubles, its volume doubles as well (Option B).
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Calculate the mass of CaCl2•2H2O required to make 100.0 mL of a 0.100 M solution. Each of the calculations below will take you through the necessary steps. You will be asked to show your answer and calculations for each. Calculate the moles of CaCl2•2H2O in 100.0 mL of a 0.100 M solution Enter your answer:
Answer:
The mass is 1.4701 grams and the moles is 0.01.
Explanation:
Based on the given question, the volume of the solution is 100 ml or 0.1 L and the molarity of the solution is 0.100 M. The moles of the solute (in the given case calcium chloride dihydride (CaCl2. H2O) can be determined by using the formula,
Molarity = moles of solute/volume of solution in liters
Now putting the values we get,
0.100 = moles of solute/0.1000
Moles of solute = 0.100 * 0.1000
= 0.01 moles
The mass of CaCl2.2H2O can be determined by using the formula,
Moles = mass/molar mass
The molar mass of CaCl2.2H2O is 147.01 gram per mole. Now putting the values we get,
0.01 = mass / 147.01
Mass = 147.01 * 0.01
= 1.4701 grams.
The mass should be considered as the 1.4701 grams and the moles should be 0.01.
Calculation of the mass and moles:Since we know that
Molarity = moles of solute/volume of solution in liters
So,
0.100 = moles of solute/0.1000
Moles of solute = 0.100 * 0.1000
= 0.01 moles
Now The mass should be
Moles = mass/molar mass
0.01 = mass / 147.01
Mass = 147.01 * 0.01
= 1.4701 grams.
hence, The mass should be considered as the 1.4701 grams and the moles should be 0.01.
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If you have 101 g of hydrogen gas (H2) and excess amount of nitrogen gas (N2), how many grams of ammonia gas (NH3) can you make?
Answer:
572. 3 g of NH3
Explanation:
Equation of the reaction: 3H2 + N2 ----> 2NH3
From the equation of reaction, 3 moles of H2 reacts with 1 mole of N2 to produce 2 moles of NH3.
Since N2 is in excess in the given reaction, H2 is the limiting reactant.
Molar mass of H2 = 2 g/mol
Molar mass of NH3 = 17 g/mol
Therefore 3 * 2 g of H2 reacts to produce 2 * 17 g of NH3
6 g of H2 produces 34 g of NH3
101 g of H2 will produce (34 * 101)/6 g of NH3 = 572.3 g of NH3
Therefore, 572.3 g of NH3 are produced
Answer:
572.33g of NH3.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
N2 + 3H2 —> 2NH3
Next, we shall determine the mass of the H2 that reacted and the mass of NH3 produced from the balanced equation. This is illustrated below:
Molar Mass of H2 = 2x1 = 2g/mol
Mass of H2 from the balanced equation = 3 x 2 = 6g
Molar Mass of NH3 = 14 + (3x1) = 17g/mol
Mass of NH3 from the balanced equation = 2 x 17 = 34g.
From the balanced equation above,
6g of H2 reacted to produce 34g of NH3.
Finally, we can determine the mass of ammonia (NH3) produced by reacting 101g of H2 as follow:
From the balanced equation above,
6g of H2 reacted to produce 34g of NH3.
Therefore, 101g of H2 will react to produce = ( 101 x 34) / 6 = 572.33g of NH3.
Therefore, 572.33g of NH3 is produced from the reaction.
Which of the following is a property of matter?
The major properties of matter are volume, mass, and shape.
All matter however too is made up of tiny particles known as atoms.
Other characteristics properties of matter which can be measured include object's density, color, length, malleability, melting point, hardness, odor, temperature, and others
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The property of matter should be volume, mass, and shape.
The following information should be considered:
The matter should be made up of small & tiny particles that we called as the atoms. It involved the density of an object, length, temperature, melting point, etc.Learn more: https://brainly.com/question/1979431?referrer=searchResults
Which accurately labels the lysosome?
Answer:
One of the organelles in eukaryotic cells that carry out digestion and waste removal.
Answer:
It's X
Explanation:
(a) show that the pressure exerted by a fluid P (in pascals) is given by P= hdg, where h is the column of the fluid in metres, d is density in kg/m3, and g is the acceleration due to gravity (9.81 m/s2). (Hint: see appendix 2.). (b) The volume of an air bubble that starts at the bottom of a lake at 5.24 degree celsius increases by a factor of 6 as it rises to the surface of water where the temperature is 18.73 degree celsius and the air pressure is 0.973 atm. The density of the lake water is 1.02 g/cm3. Use the equation in (a) to determine the depth of the lake in metres.
Answer:
56.4 m
Explanation:
volume increases by factor of 6, i.e [tex]\frac{V2}{V1}[/tex] = 6
Initial temperature T1 at bottom of lake = 5.24°C = 278.24 K
Final temperature T2 at top of lake = 18.73°C = 291.73 K
NB to change temperature from °C to K we add 273
Final pressure P2 at the top of the lake = 0.973 atm
Initial pressure P1 at bottom of lake = ?
Using the equation of an ideal gas
[tex]\frac{P1V1}{T1}[/tex] = [tex]\frac{P2V2}{T2}[/tex]
P1 = [tex]\frac{P2V2T1}{V1T2}[/tex] = [tex]\frac{0.973*6*278.24}{291.73}[/tex]
P1 = 5.57 atm
5.57 atm = 5.57 x 101325 = 564380.25 Pa
Density Ρ of lake = 1.02 g/[tex]cm^{3}[/tex] = 1020 kg/[tex]m^{3}[/tex]
acceleration due to gravity g = 9.81 [tex]m/s^{2}[/tex]
Pressure at lake bottom = pgd
where d is the depth of the lake
564380.25 = 1020 x 9.81 x d
d = [tex]\frac{564380.25}{10006.2}[/tex] = 56.4 m
The modern view of an electron orbital in an atom can best be described as
Answer:
An orbital is a region in space where there is a high probability of finding an electron.
Explanation:
The orbital is a concept that developed in quantum mechanics. Recall that Neils Bohr postulated that the electron occupied stationary states which he called energy levels. Electrons emit radiation when the move from a higher to a lower energy level. Similarly, energy is absorbed by an electron to move from a lower to a higher orbit.
This idea was upturned by the Heisenberg uncertainty principle. This principle state that the momentum and position of a particle can not be simultaneously measured with precision.
Instead of defining a 'fixed position' for the electron, we define a region in space where there is a possibility of finding an electron with a certain amount of energy. This orbital is identified by a set of quantum numbers.
Answer:
three - dimensional space that shows the probability where an electron is most likely to be found
How many grams of 02 are needed to react with 7.50g of ethanol
The osmotic pressure exerted by a solution is equal to the molarity multiplied by the absolute temperature and the gas constant . Suppose the osmotic pressure of a certain solution is measured to be at an absolute temperature o of 312. K. Write an equation that will let you calculate the molarity c of this solution.
Answer:
Explanation:
From the question, osmotic pressure exerted by a solution is equal to the MOLARITY multiplied by the absolute TEMPERATURE and the GAS CONSTANT r.
Let P = osmotic pressure,
C = molarity, then
T = absolute temperature
r=gas constant
The Osmotic pressure Equation exerted by a solution [tex]P=C*T*r[/tex]
[tex]P=CTr[/tex]
Then it was required in the question to write an equation that will let you calculate the molarity c of this solution, and this equation should contain ONLY symbols
C= molarity of the solution
P=osmotic pressure
r = gas constant
T= absolute temperature
[tex]C=P/(rT)[/tex]
The equation that will let us calculate the molarity c of this solution = [tex]C=P/(rT)[/tex]
Suppose the amount of a certain radioactive substance in a sample decays from to over a period of days. Calculate the half life of the substance. Round your answer to significant digit.
The given question is incomplete, the complete question is:
Suppose the amount of a certain radioactive substance in a sample decays from 1.30 mg to 100. ug over a period of 29.5 days. Calculate the half life of the substance Round your answer to 2 significant digits.
Answer:
The correct answer is 7.974 days.
Explanation:
Based on the given question, the concentration of a radioactive substance present in a sample get decays to 100 micro grams from 1.30 milligrams in 29.5 days. There is a need to find the half-life of the substance.
Radioactive decay is an illustration of first order reaction.
K = (2.303 / t) log [a/(a-x)]
Here a is 1.30 mg and (a-x) is 100 micrograms = 100 * 10^-3 mg or 0.1 mg, and t is 29.5 days. Now putting the values we get,
K = (2.303 /29.5)log (1.30/0.1)
= 2.303/29.5 log13
= 2.303/29.5 * 1.1139
K = 0.0869
The half-life or t1/2 is calculated by using the formula, 0.693 / K
= 0.693 / 0.0869
= 7.974 days.
A sample of chloroform, CHCl 3 , , was determined to have a molecular mass of 112.3g / (mol) . Its molecular mass is known to be 119.5g / (mol) . Calculate the absolute error and the percent error
Answer:
Explanation:
in your case ,
Meaured value = 112.3
actual value = 119.5
Absolute error= measured value - actual value
Percent error = [measured value - actual value / actual value ] x 100
Hope this help you to find the answer
What is the molar mass of CH2O2 ? ( C= 12.01 g/mol, H=1.008 g/mol, O=16.00)
Answer:
Molar Mass of CH2O2 is 46.026
Explanation:
What is the molar mass of CH2O2 ? ( C= 12.01 g/mol, H=1.008 g/mol, O=16.00)
C = 12.01g/mol
H = 1.008g/mol
O = 16g/mol
CH2O2 = 12.01+1.008x2+16x2 = 46.026g/mole
What did John Dalton publish?
Answer:
An early theory describing properties of atoms.
Explanation:
Apex
The equilibrium constant for the reaction NO2(g)+NO3(g)→N2O5(g) is 2.1x10-20 , therefore: a. At equilibrium, the concentration of products and reactants is about the same. b. At equilibrium, the concentration of products is greater than the reactants. c. At equilibrium, the concentration of reactants is greater than the products
Answer: c. At equilibrium, the concentration of reactants is greater than the products
Explanation:
Equilibrium constant for a reaction is the ratio of concentration of products to the concentration of reactants each raised to the power its stoichiometric coefficients.
For the reaction:
[tex]NO_2(g)+NO_3(g)\rightleftharpoons N_2O_5(g)[/tex]
Equilibrium constant is given as:
[tex]K_{eq}=\frac{[N_2O_5]}{[NO_2]\times [NO_3]}[/tex]
[tex]2.1\times 10^{-20}=\frac{[N_2O_5]}{[NO_2]\times [NO_3]}[/tex]
When
a) K > 1, the concentration of products is greater than the concentration of reactants
b) K < 1, the concentration of reactants is greater than the concentration of products
c) K= 1, the reaction is at equilibrium, the concentration of reactants is equal to the concentration of products
Thus as [tex]K_{eq}[/tex] is [tex]2.1\times 10^{-20}[/tex] which is less than 1,
the concentration of reactants is greater than the concentration of products
Light travels three-fourths as fast through water as it does through a vacuum.
What is water's index of refraction?
A gaseous system undergoes a change in temperature and volume. What is the entropy change for a particle in this system if the final number of microstates is 0.842 times that of the initial number of microstates
Answer: -2.373 x 10^-24J/K(particles
Explanation: Entropy is defined as the degree of randomness of a system which is a function of the state of a system and depends on the number of the random microstates present.
The entropy change for a particle in a system depends on the initial and final states of a system and is given by Boltzmann equation as
S = k ln(W) .
where S =Entropy
K IS Boltzmann constant ==1.38 x 10 ^-23J/K
W is the number of microstates available to the system.
The change in entropy is given as
S2 -S1 = kln W2 - klnW1
dS = k ln (W2/W1)
where w1 and w2 are initial and final microstates
from the question, W2(final) = 0.842 x W1(initial), so:
= 1.38*10-23 ln (0.842)
=1.38*10-23 x -0.1719
= -2.373 x 10^-24J/K(particles)
Which of the following is a chemical property of iron? It
Answer:
is capable of combining with oxygen to form iron oxide
Which statement describes a chemical property of an object? A:The object is white in color.B:The object has a powdery texture.C:The object’s density is 2.11 g/cm3.D:The object reacts with acid to form water.
Answer:
D
Explanation:
Color, texture, and density are all physical properties but reactivity is a chemical property so the answer is D.
Consider a cobalt-silver voltaic cell that is constructed such that one half-cell consists of the cobalt, Co, electrode immersed in a Co(NO3)3 solution, and the other half-cell consists of the silver, Ag, electrode immersed in a AgNO3 solution. The two electrodes are connected by a copper wire. The Co electrode acts as the anode, and the Ag electrode acts as the cathode. To maintain electric neutrality, you add a KNO3 salt bridge separating the two half-cells. Use this information to solve Parts B, C, and D.
A. The half-cell is a chamber in the voltaic cell where one half-cell is the site of the oxidation reaction and the other half-cell is the site of the reduction reaction.
Type the half-cell reaction that takes place at the anode for the cobalt-silver voltaic cell. Indicate the physical states using the abbreviation (s), (l), or (g) for solid, liquid, or gas, respectively. Use (aq) for an aqueous solution. Do not forget to add electrons in your reaction.
B. The half-cell is a chamber in the voltaic cell where one half-cell is the site of an oxidation reaction and the other half-cell is the site of a reduction reaction.
Type the half-cell reaction that takes place at the cathode for the cobalt-silver voltaic cell. Indicate physical states using the abbreviation (s), (l), or (g) for solid, liquid, or gas, respectively. Use (aq) for an aqueous solution. Do not forget to add electrons in your reaction.
Answer:
Anode half reaction;
Co(s) ----> Co^2+(aq) + 2e
Cathode half reaction;
2Ag^+(aq) + 2e-------> 2Ag(s)
Explanation:
A voltaic cell is an electrochemical cell that spontaneously produces electrical energy from chemical reactions. A voltaic cell comprises of an anode (where oxidation occurs) and a cathode (where reduction occurs). The both electrodes are connected with a wire . A salt bridge ensures charge neutrality in the anode and cathode compartments. Electrons flow from anode to cathode.
For the cell referred to in the question;
Anode half reaction;
Co(s) ----> Co^2+(aq) + 2e
Cathode half reaction;
2Ag^+(aq) + 2e-------> 2Ag(s)
the reaction between aluminum and iron(iii) oxide can generate temperatures approaching 3000c and is used in welding metals. In one process, 268g of Al are reacted with 501g of Fe2O3. identify the limiting reagent and calculate the theoretical mass
Answer:
- Iron (III) oxide is the limiting reactant.
- [tex]m_{Al_2O_3}=319.9gAl_2O_3[/tex]
- [tex]m_{Fe}=350.4gFe[/tex]
Explanation:
Hello,
In this case, we consider the following reaction:
[tex]2Al + Fe_2O_3 \rightarrow Al_2O_3 +2Fe[/tex]
Thus, for identifying the limiting reactant we should compute the available moles of aluminium in 268 g:
[tex]n_{Al}=268gAl*\frac{1molAl}{26.98gAl} =9.93molAl[/tex]
Next, we compute the moles of aluminium that are consumed by 501 grams of iron (III) oxide via their 2:1 molar ratio:
[tex]n_{Al}^{consumed}=501gFe_2O_3*\frac{1molFe_2O_3}{159.69gFe_2O_30}*\frac{2molAl}{1molFe_2O_3}=6.27molAl[/tex]
Thus, we notice there are less consumed moles of aluminium than available, for that reason, it is in excess; therefore, the iron (III) oxide is the limiting reactant.
Moreover, the theoretical mass of aluminium oxide is:
[tex]m_{Al_2O_3}=6.27molAl*\frac{1molAl_2O_3}{2molAl} *\frac{101.96gAl_2O_3}{1molAl_2O_3} =319.9gAl_2O_3[/tex]
And the theoretical mass of iron is:
[tex]m_{Fe}=6.27molAl*\frac{2molFe}{2molAl} *\frac{55.845 gFe}{1molFe} =350.4gFe[/tex]
Best regards.
Which diagram represents this molecule?
Answer:
C
Explanation:
The molecule has 8 carbon atoms joined by 7 C-C bonds.
The first two diagrams show 6 carbon atoms, not 8.
The last two diagrams show line segments representing C-C bonds. Only choice C shows 7 such segments.
The appropriate choice is C.
Answer:
C.
Explanation:
g Reduction involves the A) loss of neutrons, gain of electrons, and an increase in oxidation state. B) loss of neutrons. C) increase in oxidation state. D) gain of electrons and an increase in oxidation state. E) gain of electrons.
Answer:
E. Gain of electrons
Explanation:
A reduction reaction is one part of the two concurrent reactions that take place in a redox (reduction-oxidation) reaction.
During reduction, an atom gains electrons from a donor atom, and it's oxidation number becomes smaller.
Option A is wrong because reduction does not increase oxidation state nor are neutrons involved
Option B is wrong because reduction is not a nuclear reaction (does not involve the nucleons)
Option C is wrong because reduction leads to reduction in oxidation state
Option D is wrong leads to a reduction in oxidation state when electrons are gained
Option E is correct because reduction involves gain of electrons
What is the mass of 3.75 moles of NaCI? ( Na= 22.99g/mol, CI= 35.45 g/mol)
Answer:
219.15 grams
Explanation:
What is the mass of 3.75 moles of NaCI? ( Na= 22.99g/mol, CI= 35.45 g/mol)
Mole of Na = 22.99g
Mole of Cl = 35.45g
For NaCl we have ratio of 1:1, so we have 1 Na for every Cl
So we just add the two together to get the molar mass of NaCl which is
22.99 + 35.45 = 58.44g/mol
And we know we have 3.75 moles of NaCl so we multiply that by the molar mass of NaCl to get our answer
3.75 x 58.44 = 219.15grams
Find the age ttt of a sample, if the total mass of carbon in the sample is mcmcm_c, the activity of the sample is AAA, the current ratio of the mass of 14 6C 614C to the total mass of carbon in the atmosphere is rrr, and the decay constant of 14 6C 614C is λλlambda. Assume that, at any time, 14 6C 614C is a negligible fraction of the total mass of carbon and that the measured activity of the sample is purely due to 14 6C 614C. Also assume that the ratio of mass of 14 6C 614C to total carbon mass in the atmosphere (the source of the carbon in the sample) is the same at present and on the day when the number of 14 6C 614C atoms in the sample was set. Express your answer in terms of the mass mamam_a of a 14 6C 614C atom, mcmcm_c, AAA, rrr, and λλlambda. View Available Hint(s)
Answer:
Explanation:
An artifact is found in a desert cave. The anthropologists who found this artifact would like to know its age. They find that the present activity of the artifact is 9.25 decays/s and that the mass of carbon in the artifact is 0.100 kg. To find the age of the artifact, they will need to use the following constants:
r=1.2
The activity of carbon 14 is
[tex]A=A_0e^{\lambda t}[/tex]
where,
[tex]A_0[/tex] is the initial activity of the compound
Solve for t
[tex]-\lambda t=In\frac{A}{A_0}[/tex]
[tex]t=-\frac{1}{\lambda} In(\frac{A}{A_0} )[/tex]
[tex]=-\frac{1}{\lambda} In(\frac{A}{\lambda r(\frac{m_c}{m_a} )} )[/tex]
since,
[tex]A_0=\lambda r(\frac{m_c}{m_a} )[/tex]
[tex]=-\frac{1}{\lambda} In(\frac{A\ m_a}{\lambda r m_c} )[/tex]
Now, the age of the artifact is
[tex]=-\frac{1}{\lambda} In(\frac{A\ m_a}{\lambda r m_c} )[/tex]
[tex]=-\frac{1}{1.21\times 10^{-4}} In(\frac{(9.25)(2.32\times 10^{-26}}{1.21\times 10^{-4}(\frac{1}{3.15569\times10^7} )(1.2\times 10^{-12})(0.100)}} )\\\\=6303.4 \ years[/tex]
to two significant figure = 6300 years
