Answers
Answer:
2.0 g Na
Explanation:
Stoichiometry.
8.4g sodium hydrogen citrate x (1 mol sodium hydrogen citrate / 192 g sodium hydrogen citrate) x (2 mol Na/1 mol sodium hydrogen citrate) x (23g Na/1 mol Na)
^write it out it makes more sense that way
Related Questions
If one contraction cycle in muscle requires 55 kJ55 kJ , and the energy from the combustion of glucose is converted with an efficiency of 35%35% to contraction, how many contraction cycles could theoretically be fueled by the complete combustion of one mole of glucose? Round your answer to the nearest whole number.
Answers
Answer:
18 moles
Explanation:
Here the combustion of one mole of glucose ----> carbon dioxide + water, releases 2870 kilojoules / moles.
_______________________________________________________
With one contraction cycle requiring 55 kilojoules,
2870 / 55 ≈ 52.18
And with the efficiency being 35 percent,
52.1818..... * 0.35 = ( About ) 18 moles
Hope that helps!
What are the concentrations of Cu2+, NH3, and Cu(NH3)42+ at equilibrium when 18.8 g of Cu(NO3)2 is added to 1.0 L of a 0.800 M solution of aqueous ammonia? Assume that there is no volume change upon the addition of the solid, and that the reaction goes to completion and forms Cu(NH3)42+.
Answers
Answer:
Explanation:
Cu(NO₃)₂ + 4NH₃ = Cu(NH₃)₄²⁺ + 2 NO₃⁻
187.5 gm 4M 1 M
187.5 gm reacts with 4 M ammonia
18.8 g reacts with .4 M ammonia
ammonia remaining left after reaction
= .8 M - .4 M = .4 M .
187.5 gm reacts with 4 M ammonia to form 1 M Cu(NH₃)₄²⁺
18.8 g reacts with .4 M ammonia to form 0.1 M Cu(NH₃)₄²⁺
At equilibrium , the concentration of Cu²⁺ will be zero .
concentration of ammonia will be .4 M
concentration of Cu(NH₃)₄²⁺ formed will be 0.1 M
how many grams are there in 9.4x10^25 molecules of H2
Answers
Answer:
You start with 9.4 x 1025 molecules of H2.
You know that an Avogadro's number of molecules of H2 has a mass of 2.0 g.
To solve, 9.4 x 1025 molecules H2 x (2.0 g H2 / 6.023 x 1023 molecules H2) = 312. g H2
Explanation:
Enter an equation for the formation of C2H5OH(l) from its elements in their standard states. Enter any reference to carbon as C(s). Express your answer as a chemical equation. Identify all of the phases in your answer.
Answers
Answer:
C(s) + 3 H₂(g) + 1/2 O₂(g) ⇒C₂H₅OH(l)
Explanation:
Ethanol (C₂H₅OH) is an alcohol and it is formed by carbon (C), H (hydrogen) and O (oxygen) atoms. These elements in their standard states are:
C: C(s), it is solid, could be graphite, diamond, among others.
H: H₂(g), it is a diatomic gas.
O: O₂(g), it is a diatomic gas.
So, we can write the equation for the formation of C₂H₅OH from C(s), H₂ and O₂ as follows:
C(s) + H₂(g) + O₂(g) ⇒C₂H₅OH(l)
Finally, we have to balance the equation by adding the estequiometrical coefficients:
C(s) + 3 H₂(g) + 1/2 O₂(g) ⇒C₂H₅OH(l)
2C(s)+3[tex]H_{2} [/tex](g)+[tex]\frac{1}{2} [/tex][tex]O_{2} [/tex](g)→[tex]C_{2} [/tex][tex]H_{5} [/tex]OH(l)
Explanation:
Standard state of carbon: C(s)
Standard state of oxygen: [tex]O_{2} [/tex](g)
Standard State of Hydrogen: [tex]H_{2} [/tex](g)
Then balance the equation C2H5OH(l) to get 2C(s)+3[tex]H_{2} [/tex](g)+[tex]\frac{1}{2} [/tex][tex]O_{2} [/tex](g)→[tex]C_{2} [/tex][tex]H_{5} [/tex]OH(l).
When ethanol, C2H5OH (a component in some gasoline mixtures) is burned in air, one molecule of ethanol combines with three oxygen molecules to form two CO2 molecules and three H2O molecules.
A) Write the balanced chemical equation for the reaction described.
B) How many molecules of CO2 and H2O would be produced when 2 molecules ethanol are consumed? Equation?
C) How many H2O molecules are formed, then 9 O2 molecules are consumed? What conversion factor did you use? Explain!
D) If 15 ethanol molecules react, how many molecules O2 must also react? What conversion factor did you use? Explain!
Answers
Answer:
1) C2H5OH(l)+3O2(g)⟶2CO2(g)+3H2O(l)
2) four molecules of CO2 will be produced and six molecules of water
3)9 molecules of water are formed when 9 molecules of oxygen are consumed.
4) 45 molecules of oxygen
Explanation:
The balanced chemical reaction equation is shown here and must guide our work. When ethanol is burned in air, it reacts as shown;
C2H5OH(l)+3O2(g)⟶2CO2(g)+3H2O(l)
Hence, if we use 2 molecules of ethanol, the balanced reaction equation will look like this;
2C2H5OH(l)+6O2(g)⟶4CO2(g)+6H2O(l)
Hence four molecules of CO2 are formed and six molecules of water are formed
From the balanced stoichiometric equation;
3 molecules of oxygen yields 3 molecules of water
Therefore, 9 molecules of oxygen will yield 9 × 3/3 = 9 molecules of water
Therefore, 9 molecules of water are formed when 9 molecules of oxygen are consumed.
From the reaction equation;
1 molecule of ethanol reacts with 3 molecules of oxygen
Therefore 15 molecules of ethanol will react with 15 × 3/1 = 45 molecules of oxygen
Why does a chemical change occur when copper is heated?
Answers
Answer:
When copper is heated, it decomposes to form copper oxide and carbon dioxide. It is an endothermic reaction, which means that it absorbs heat. When heated, copper is easily bent or molded into shapes.
Explanation:
Why need to add NaAlF6 to Al2O3?
Answers
So in the electrolytic reduction of alumina, cryolite is added along with fluorspar to–
– decrease melting point of alumina
– decrease viscosity of electrolyte (CaF
2is used) – increase conductivity
Hope this helps
am i correct if not correct me please
Answers
Answer:
D. Hund's rule
Explanation:
Not sure, but I would go with Hund's since it talks about filing electrons in each orbital before you can pair them up. The reason sulfur has lower ionization is because it has one set of paired electrons which makes the orbital unstable whereas phosphorus has 3 unpaired e's which means it is more stable. Thus it is easier to remove electron from sulfur hence lower ionization energy.
Carbon dioxide and water vapor are variable gases because _____.
Answers
Answer: their amounts vary throughout the atmosphere
Explanation:
There is very little that travels over the atmosphere
Vary=very little
Hope that helps
Determine the quantity (g) of pure MgSO4 in 2.4 g of MgSO4•7H2O. Show your work.
Answers
Answer: The quantity of pure [tex]MgSO_4[/tex] in 2.4 g of [tex]MgSO_4.7H_2O[/tex] is 1.17 g
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar Mass}}=\frac{2.4g}{246g/mol}=0.0098moles[/tex]
As 1 mole of [tex]MgSO_4.7H_2O[/tex] contains = 1 mole of [tex]MgSO_4[/tex]
Thus 0.0098 moles of [tex]MgSO_4.7H_2O[/tex] contains = [tex]\frac{1}{1}\times 0.0098=0.0098mole[/tex] of [tex]MgSO_4[/tex]
Mass of [tex]MgSO_4=0.0098mol\times 120g/mol=1.17g[/tex]
Thus the quantity of pure [tex]MgSO_4[/tex] in 2.4 g of [tex]MgSO_4.7H_2O[/tex] is 1.17 g
g The atomic mass of an element is equal to ________. The atomic mass of an element is equal to ________. its mass number one-twelfth of the mass of a carbon-12 atom a weighted average mass of all of the naturally occurring isotopes of the element its atomic number the average mass of all of the naturally occurring isotopes of the element
Answers
Answer:
Total numbe of protons and neutrons in a single atom of that element
Explanation:
Hello,
I'll answer the question by filling in the blank spaces
"The atomic mass of an element is equal to the total number of proton and neutron in a particular atom of the element. The atomic mass of an element is equal to the atomic weight. Its mass number one-twelfth of the mass of carbon-12 atom a weighted mass of all naturally occurring isotopes of the elements. Its atomic mass is the average mass of all the naturally occurring isotopes of the element."
The atomic mass of an element is the total number of protons and neutrons in a single atom of that element.
The atomic mass of an element is equal to a weighted average mass of all of the naturally occurring isotopes of the element. The correct answer is option 2.
Isotopes are elements with the same number of protons (atomic number) but differing numbers of neutrons (mass number).
Most elements exist in nature as a mixture of isotopes, each with a different mass number and abundance. The atomic mass of an element is computed by adding the masses of all isotopes, multiplying by their relative abundance, and dividing by the total abundance of all isotopes.
This gives a weighted average mass that corresponds to the normal mass of an element's atom in nature.
Therefore, the correct answer is option 2. to a weighted average mass of all of the naturally occurring isotopes of the element.
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How many moles of CO2 can be produced by the complete reaction of 1.0 g of lithium carbonate with excess hydrochloric acid (balanced chemical reaction is given below)? Li2CO3(s) + 2HCl(aq) --> 2LiCl(aq) + H2O(l) + CO2(g) Question 1 options: 1.7 g 1.1 g 0.60 040 g
Answers
Answer:Mass of CO2 = 0.60g
Explanation:
Given the chemical rection
Li2CO3(s) + 2HCl(aq) --> 2LiCl(aq) + H2O(l) + CO2(g
No of moles = mass / molar mass
molar mass Li2CO3 = Molecular mass calculation: 6.941 x 2 + 12.0107 + 15.9994 x 3 =
= 73.8909 g/mol
therefore Number of moles Li2CO3 = 1.0g / 73.89 g/mol
= 0.0135 moles Li2CO3
From our given Balanced equation, shows that
Li2CO3(s) + 2HCl(aq) --> 2LiCl(aq) + H2O(l) + CO2(g
1 mole Li2CO3 produces 1 mole CO2
therefore 0.0135 mol Li2CO3 will produce 0.0135 moles of CO2
Also
No of moles = mass / molar mass
Mass = No of moles x molar mass
molar mass of CO2=12.0107 + 15.9994 x 2=44.0095 g/mol
Mass of CO2= 0.0135 X 44.0095 g/mol =0.594≈0.60g
Describe the buffer capacity of the acetic acid buffer solution in relation to the addition of both concentrated and dilute acids and bases.
Answers
Answer:
The answer is in the explanation
Explanation:
Acetic acid, CH₃COOH, is a weak acid that will produce a buffer when its conjugate base, CH₃COO⁻, acetate ion, is added to the solution.
That is because a buffer is the mixture of a weak acid and its conjugate base or vice versa.
When an acid (HX) is added to the solution, the acetate ion will react producing acetic acid, thus:
CH₃COO⁻ + HX → CH₃COOH + X⁻
For this reason, the pH doesn't change abruptly because H⁺ ions are not produced.
Now, if a base (BOH) is added to the buffer, CH₃COOH will react producing acetate ion and water, thus:
CH₃COOH + BOH → CH₃COO⁻ + H₂O + B⁺.
In the same way, there are not produced free OH⁻ and the pH doesn't change significantly.
Harvey kept a balloon with a volume of 348 milliliters at 25.0˚C inside a freezer for a night. When he took it out, its new volume was 322 milliliters, but its pressure was the same. If the final temperature of the balloon is the same as the freezer’s, what is the temperature of the freezer?
Answers
Answer:
[tex]T2=276K[/tex]
Explanation:
Given:
Initial volume of the balloon V1 = 348 mL
Initial temperature of the balloon T1 = 255C
Final volume of the balloon V2 = 322 mL
Final temperature of the balloon T2 =
To calculate T1 in kelvin
T1= 25+273=298K
Based on Charles law, which states that the volume of a given mass of a ideal gas is directly proportional to the temperature provided that the pressure is constant. It can be applied using the below formula
[tex](V1/T1)=(V2/T2)[/tex]
T2=( V2*T1)/V1
T2=(322*298)/348
[tex]T2=276K[/tex]
Hence, the temperature of the freezer is 276 K
Answer: 276 kelvins
Explanation:
the reaction below is at equilibrium. What would happen if more carbon were added ?
Answers
Answer:
B
Explanation:
If more carbon were added, the equilibrium position would shift to produce more products.
What is equilibrium?In a chemical reaction chemical equilibrium is defined as the state at which there is no further change in concentration of reactants and products.
If the concentration of one (or more) of the reactants or products is increased the equilibrium will shift to decrease the concentration.
Or if the temperature is decreased the equilibrium will shift to increase the temperature by favouring the exothermic reaction.
Hence, if more carbon were added, the equilibrium position would shift to produce more products.
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A solution is prepared by mixing 5.00 mL of 0.100 M HCl and 2.00 mL of 0.200 M NaCl. What is the molarity of chloride ion in this solution?
Answers
Answer:
0.129 M
Explanation:
0.100 M HCl = 0.100 mol/L solution HCl
5.00 mL = 0.00500 L solution HCl
0.100 mol/L HCl * 0.00500 L = 0.000500 mol HCl
HCl ------> H+ + Cl-
1 mol 1 mol
0.000500 mol 0.000500 mol
0.200 M NaCl = 0.200 mol/L solution NaCl
2.00 mL = 0.00200 L solution NaCl
0.200 mol/L NaCl*0.00200 L = 0.000400 mol NaCl
NaCl ------> Na+ + Cl-
1 mol 1 mol
0.000400 mol 0.000400 mol
Chloride ion altogether (0.000500 mol + 0.000400 mol) =0.000900 mol
Solution altogether (0.00500 L+0.00200 L) = 0.00700L
Molarity (Cl-)= solute/solution = 0.000900 mol/0.00700L = 0.129 mol/L=
= 0.129 M
The diagram below shows that the periodic table is divided into different blocks.
A periodic table is shown. The main table consists of seven rows; two additional rows are shown below. In each block, the first column is labeled and the remaining columns are empty. The s-block is shaded in yellow and comprises the first two columns, plus one cell at the far side of the table. The first column has seven rows with entries 1 s, 2 s, 3 s, 4 s, 5 s, 6 s, and 7 s. A lone cell labeled 1 s appears at the top far right corner, aligned with the 1 s cell in the first column. The d-block is shaded in blue and contains 10 columns and 3 or 4 rows. The first column is directly to the right of the s-block. The first entry in the first d-block column aligns with the 4 s block, and is labeled 3d; further entries in that column are 4 d, 5 d, and 6 d. The first three columns in the block are four entries long; the remaining columns are three entries long, losing the bottom entry. The p-block is shaded in orange, and has 6 columns and 5 rows. The top row aligns with the 2 s block; entrie
Elements that have complete valence electron shells are mostly found in the
s block.
d block.
p block.
Answers
Answer:
p block.
Explanation:
jus took the test
Answer:
c p block
Explanation:
Air is compressed from an inlet condition of 100 kPa, 300 K to an exit pressure of 1000 kPa by an internally reversible compressor. Determine the compressor power per unit mass flow rate if the device is (a) isentropic, (b) polytropic with n =1.3, (c) isothermal
Answers
Answer:
(a) [tex]W_{isoentropic}=8.125\frac{kJ}{mol}[/tex]
(b) [tex]W_{polytropic}=7.579\frac{kJ}{mol}[/tex]
(c) [tex]W_{isothermal}=5.743\frac{kJ}{mol}[/tex]
Explanation:
Hello,
(a) In this case, since entropy remains unchanged, the constant [tex]k[/tex] should be computed for air as an ideal gas by:
[tex]\frac{R}{Cp_{air}}=1-\frac{1}{k} \\\\\frac{8.314}{29.11} =1-\frac{1}{k}\\[/tex]
[tex]0.2856=1-\frac{1}{k}\\\\k=1.4[/tex]
Next, we compute the final temperature:
[tex]T_2=T_1(\frac{p_2}{p_1} )^{1-1/k}=300K(\frac{1000kPa}{100kPa} )^{1-1/1.4}=579.21K[/tex]
Thus, the work is computed by:
[tex]W_{isoentropic}=\frac{kR(T_2-T_1)}{k-1} =\frac{1.4*8.314\frac{J}{mol*K}(579.21K-300K)}{1.4-1}\\\\W_{isoentropic}=8.125\frac{kJ}{mol}[/tex]
(b) In this case, since [tex]n[/tex] is given, we compute the final temperature as well:
[tex]T_2=T_1(\frac{p_2}{p_1} )^{1-1/n}=300K(\frac{1000kPa}{100kPa} )^{1-1/1.3}=510.38K[/tex]
And the isentropic work:
[tex]W_{polytropic}=\frac{nR(T_2-T_1)}{n-1} =\frac{1.3*8.314\frac{J}{mol*K}(510.38-300K)}{1.3-1}\\\\W_{polytropic}=7.579\frac{kJ}{mol}[/tex]
(c) Finally, for isothermal, final temperature is not required as it could be computed as:
[tex]W_{isothermal}=RTln(\frac{p_2}{p_1} )=8.314\frac{J}{mol*K}*300K*ln(\frac{1000kPa}{100kPa} ) \\\\W_{isothermal}=5.743\frac{kJ}{mol}[/tex]
Regards.
The acetic acid/acetate buffer system is a common buffer used in the laboratory. Write the equilibrium equation for the acetic acid/acetate buffer system. The formula of acetic acid is CH3CO2H .
Answers
Answer:
CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺
Explanation:
A buffer is defined as the mixture of a weak acid and its conjugate base or vice versa.
For the acetic acid buffer, CH₃CO₂H is the weak acid and its conjugate base is the ion without H⁺, that is CH₃CO₂⁻. The equilibrium equation in water knowing this is:
CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺In the equilibrium, the acid is dissociated in the conjugate base and the hydronium ion.
The acetic acid/acetate buffer system is a common buffer used in the laboratory, the equilibrium equation for the acetic acid/acetate buffer system. The formula of acetic acid is CH3CO2H -
CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺
An acid buffer is a solution that contains roughly the same concentrations of a weak acid and its conjugate base.
an acetate buffer contains roughly equal concentrations of acetic acid and acetate ion.Both are in chemical equilibrium with each other.The equation is:
CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺
where CH₃CO₂H - acetic acid
and, CH₃CO₂⁻ acetate ion
Thus, CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺ is the equilibrium equation for the acetic acid/acetate buffer system.
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Enter your answer in the provided box. On a cool, rainy day, the barometric pressure is 739 mmHg. Calculate the barometric pressure in centimeters of water (cmH2O) (d of Hg = 13.5 g/mL; d of H2O = 1.00 g/mL).
Answers
Answer:
997.65cmH2O
Explanation:
Barometric pressure = 739 mmHg
density of Hg = 13.5 g/ml
density of water (H2O) = 1.00 g/ml
Calculate Barometric pressure in centimetres of water ( cmH20)
equate the barometric pressure of Hg and water
739 * 13.5 * 9.8 = x * 1 * 9.81
x ( barometric pressure of water in mmH2O ) = 739 *13.5 / 1 = 9976.5mmH2O
in cmH2O = 997.65cmH2O
How many grams of POCl3 are produced when 225.0 grams of P4O10 and 675.0 grams of PCl5 react? This is the balance equation P4O10 + 6PCl5 → 10POCl3
Answers
Answer:
900g of POCl₃
Explanation:
Hello,
To solve this question, we'll require the equation of reaction.
P₄O₁₀ + 6PCl₅ → 10POCl₃
Molar mass of P₄O₁₀ = 283.886 g/mol
Molar mass of PCl₅ = 208.24 g/mol
Molar mass of POCl₃ = 153.33 g/mol
But Number of moles = mass / molar mass
Mass = molar mass × number of moles
Mass of POCl₃ = 153.33 × 10 = 1533.3g
Mass of PCl₅ = 208.24 × 6 = 1249.44g
Mass of P₄O₁₀ = 283.886 × 1 = 283.886g
From the equation of reaction,
283.886g of P₄O₁₀ + 1249.44g of PCl₅ produces 1533.33g of POCl₃
I.e 1533.33g of reactants produces 1533.33g of product (law of conservation of mass)
Therefore, (225g of P₄O₁₀ + 675g of PCl₅) = 900g will give x g of POCl₃.
1533.33g of reactants = 1533.33g of products
900g of reactants = x g of products
x = (900 × 1533.33) / 1533.33
x = 900g of POCl₃
What are 3 characteristics of chemical reactions
Answers
Answer:
Evolution of gas.
Formation of a precipitate.
Change in color.
Explanation:
The atomic mass of gallium is 69.72 . The density of iron is 7.87 . The atomic mass of iron is 55.847 . Calculate the number of gallium atoms in one ton (2000 pounds) of gallium. (Enter your answer to three significant figures.)
Answers
Answer:
the atomic mass of any elemet contains avogardo numberof atoms
In case of Gallium,
69.72 gram is atomic mass and it cotnains around 6.023*10^23 atoms of Gallium
but, 2000 punds = 907184.7 grams
907184.7 gram of gallium contains= 6.023*10^23* 907184/69.72
= 79 *10^26 atoms
Explanation:
Which scenario describes an interaction between two of Earth's spheres?
Water flows from a stream to a lake.
Gravity moves rocks to another location.
Lions use energy to catch other animals for food.
Bears dig big holes in the ground to protect their young.
Answers
The correct answer is D. Bears dig big holes in the ground to protect their young
Explanation:
The Earth spheres include the biosphere (life in the Earth), the hydrosphere (water bodies), the geosphere (rocks and other elements that compose land and soil), and the atmosphere (gases that compose the air). In this context, there is an interaction between two spheres: the biosphere and the geosphere, when a bear digs holes in the ground because a living organism that is part of the biosphere is modifying the structure and shape of superficial soil, which is part of the geosphere.
Answer: D
Explanation:
what’s the SI unit of time ?
Answers
Answer:
The answer is A
Explanation:
describe how would you use chromatography to show whether blue ink contains a single purple dye or a mixture of dyes
Answers
Explanation:
if the solution placed on the chromatography is pure there will be formation of one spot from the baseline and will go farthest to the front line unlike the impure one
With ink chromatography, a small amount of ink is added to the paper, one end is submerged in water, and the different colors of the ink are revealed as the water moves up the paper. All of this is made possible by the water base and variety of salabilities or densities that make up ink.
What is chromatography ?Separating mixture's constituent parts by chromatography is a method. The mixture is dissolved in a material known as the mobile phase to start the process, which then transports it through a material known as the stationary phase.
A little dot of the ink to be separated is placed at one end of a strip of filter paper to perform ink chromatography. The paper strip's opposite end is submerged in a solvent. The solvent moves up the paper strip, dissolving the chemical combination as it goes and pulling it up the paper.
Throughout the experiment, the dyes are pulled along by the mobile phase (water) as it gently advances up the stationary phase (paper).
Thus, With ink chromatography, a small amount of ink is added to the paper, one end is submerged in water.
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Give the characteristic of a zero order reaction having only one reactant. a. The rate of the reaction is not proportional to the concentration of the reactant. b. The rate of the reaction is proportional to the square of the concentration of the reactant. c. The rate of the reaction is proportional to the square root of the concentration of the reactant. d. The rate of the reaction is proportional to the natural logarithm of t
Answers
Answer:
a. The rate of the reaction is not proportional to the concentration of the reactant.
Explanation:
The rate expression for a zero order reaction is given as;
A → Product
Rate = k[A]⁰
[A]⁰ = 1
Rate = K
GGoing through the options;
a) This is correct because in the final form of the rate expression, the rate is independent of the concentration.
b) This option is wrong
c) This option is also wrong
d) Like options b and c this is also wrong becaus ethere is no relationship between either the concentration or t.
A certain element consists of two stable isotopes. The first has a mass of 62.9 amu and a percent natural abundance of 69.1 %. The second has a mass of 64.9 amu and a percent natural abundance of 30.9 %. What is the atomic weight of the element?
Answers
Answer:
63.518
Explanation:
The following data were obtained from the question:
Mass of Isotope A = 62.9 amu
Abundance of isotope A (A%) = 69.1%
Mass of isotope B = 64.9 amu
Abundance of isotope B (B%) = 30.9%
Atomic weight of the element =..?
The atomic weight of the element can be obtained as follow:
Atomic weight = [(Mass of A x A%)/100] + [(Mass of B x B%) /100]
Atomic weight = [(62.9 x 69.1)/100] + [(64.9 x 30.9)/100]
Atomic weight = 43.4639 + 20.0541
Atomic weight = 63.518
Therefore, the atomic weight of the element is 63.518.
On a hot summer day, the density of air at atmospheric pressure at 35.5°C is 1.1970 kg/m3. (a) What is the number of moles contained in 1.00 m3 of an ideal gas at this temperature and
Answers
Complete question:
On a hot summer day, the density of air at atmospheric pressure at 35.5°C is 1.1970 kg/m3. (a) What is the number of moles contained in 1.00 m3 of an ideal gas at this temperature and pressure.
Answer:
The number of moles contained by an ideal gas at this temperature and pressure is 41.32 moles.
Explanation:
Given;
density of dry air, ρ = 1.1970 kg/m³
temperature of the air, T = 35.5°C = 273 + 35.5 = 308.5 K
air volume, V = 1 m³
Apply ideal gas law for dry to calculate the air pressure;
[tex]P = \rho R_dT[/tex]
where;
P is the air pressure
ρ is the air density
Rd is gas constant for dry air = 287 J/kg/K
P = 1.197 x 287 x 308.5 = 105,981.78 Pa
(a) Now, determine the number of moles contained by an ideal gas at this temperature and pressure, by applying ideal gas law;
PV = nRT
where;
P is the pressure of the gas (Pa)
V is the volume of the gas (m³)
n is number of gas moles
R is gas constant = 8.314 m³.Pa / mol.K
T is temperature (K)
n = (PV) / (RT)
n = (105,981.78 x 1) / (8.314 x 308.5)
n = 41.32 moles
Therefore, the number of moles contained by an ideal gas at this temperature and pressure is 41.32 moles.
The number of moles of an ideal gas at this temperature and pressure is 41.5 moles.
Given that;
Density of dry air = 1.1970 kg/m3
Pressure of dry air = ?
Temperature of dry air = 35.5°C + 273 = 308.5 K
Hence;
P = Density × gas constant of dry air × Temperature
P = 1.1970 kg/m3 × 287.1 J/Kg/K × 308.5 K
P = 106019 Pa or 1.05 atm
Using the ideal gas equation;
PV = nRT
n = PV/RT
n = 1.05 atm × 1000 L/0.082 atmL/K.mol × 308.5 K
n = 41.5 moles
Learn more: https://brainly.com/question/11897796
When comparing the two chair conformations for a monosubstituted cyclohexane ring, which type of substituent shows the greatest preference for occupying an equatorial position rather than an axial position
Answers
Answer:
See the explanation
Explanation:
In this case, we have to keep in mind that in the monosubstituted product we only have to replace 1 hydrogen with another group. In this case, we are going to use the methyl group [tex]CH_3[/tex].
In the axial position, we have a more steric hindrance because we have two hydrogens near to the [tex]CH_3[/tex] group. If we have more steric hindrance the molecule would be more unstable. In the equatorial positions, we don't any interactions because the [tex]CH_3[/tex] group is pointing out. If we don't have any steric hindrance the molecule will be more stable, that's why the molecule will the equatorial position.
See figure 1
I hope it helps!