Answer:
Substance B
Explanation:
Molar heat of A = 31.2J/mole.°C
Molar heat of B = 11.2 J/mole∙°C.
The molar heat of a substance is the amount of heat that must be added to a mole of a substance to raise the temperature by 1°C.
Answer:
Four moles of electrons
Explanation:
The reactions in a breathalyzer are redox reactions. Fuel cell breathalyzers consists of fuel cells with platinum electrodes. The current produced depends on the amount of alcohol in the breath. Detection of alcohol involves the oxidation of ethanol to ethanoic acid. The two half cells set in the process are;
Anode;
C2H5OH(aq) + 4OH^-(aq) ----------> CH3COOOH(aq) + 3H2O(l) + 4e
Cathode;
O2(g) + 2H2O(l) +4e--------> 4OH^-(aq)
Hence four electrons are transferred in the process.
Answer:
Compound X has the formula C8H14.
X reacts with one molar equivalent of hydrogen in the presence of a palladium catalyst to form a mixture of cis- and trans-1,2-dimethyl cyclohexane. Treatment of X with ozone followed by zinc in aqueous acid gives a ketone plus formaldehyde (CH2=O). What is the structure of X?
Explanation:
The degree of unsaturation in the given molecule C8H14 is:
DU=(Cn+1)-Hn/2-Xn/2+Nn/2
where,
Cn=number of carbon atoms
Hn=number of hydrogen atoms
Xn=number of halogen atoms
Nn=number of nitrogen atoms
C8H14:
DU=(8+1)-14/2
=>DU=9-7 =2
Hence, the given molecule will have either two double bonds or one double bond and one ring or two rings.
X reacts with one molar equivalent of hydrogen in the presence of a palladium catalyst to form a mixture of cis- and trans-1,2-dimethylcyclohexane.
This indicates that the molecule X has one double bond and one ring that is cyclohexane ring.
Treatment of X with ozone follwed by zinc in aqueous acid gives a ketone plus formaldehyde (CH2=O).
So, the molecule has a ring and double bond CH2.
Based on the given data the structure of compound X is shown below:
The reaction sequence is shown below:
Compound X, with the formula C8H14, reacts with hydrogen to form 1,2-dimethylcyclohexane. When treated with ozone and zinc, it yields a ketone and formaldehyde. Therefore, the structure of X is 1,2-dimethylcyclohexane.
X is a compound with the formula C8H14. The reaction of X with hydrogen in the presence of a palladium catalyst produces a mixture of cis- and trans-1,2-dimethylcyclohexane. When X is treated with ozone followed by zinc in aqueous acid, it forms a ketone and formaldehyde (CH2=O).
This information tells us that compound X is a cycloalkane with two methyl groups. Since it reacts with hydrogen to form 1,2-dimethylcyclohexane, we know that X must have a cyclohexane ring with two methyl groups at the 1 and 2 positions. The cis and trans isomers of 1,2-dimethylcyclohexane have different arrangements of the methyl groups relative to each other.
Thus, the structure of compound X is 1,2-dimethylcyclohexane.
#SPJ3
Answer:
Explanation:
# moles that exist in 1.9 X 10 23 =
= # of atoms/# of Avogadro 's num
= 1.9 X 10 23 / 6.02x10 23
= 0.266 mole of Pb
now we calculate the mass
mass of lead = # mol x m.wt
= 0.266 X 106.4
= 28.30 gram
Answer : The concentration of remains at equilibrium will be, 0.37 M
Explanation : Given,
Equilibrium constant = 4.90
Initial concentration of = 2.00 M
The balanced equilibrium reaction is,
Initial conc. 2 M 0 0
At eqm. (2-2x) M x M x M
The expression of equilibrium constant for the reaction will be:
Now put all the values in this expression, we get :
By solving the term 'x' by quadratic equation, we get two value of 'x'.
Now put the values of 'x' in concentration of remains at equilibrium.
Concentration of remains at equilibrium =
Concentration of remains at equilibrium =
From this we conclude that, the amount of substance can not be negative at equilibrium. So, the value of 'x' which is equal to 1.291 M is not considered.
Therefore, the concentration of remains at equilibrium will be, 0.37 M
217g of water.
What is the molality of the solution?
Answer:
THE MOLARITY IS 2.22 MOL/DM3
Explanation:
The solution formed was as a result of dissolving 37.5 g of Na2S in 217 g of water
Relative molecular mass of Na2S = ( 23* 2 + 32) = 78 g/mol
Molarity in g/dm3 is the amount of the substance dissolved in 1000 g or 1 L of the solvent. So we have;
37.5 g of Na2S = 217 g of water
( 37.5 * 1000 / 217 ) g = 1000 g of water
So, 172.81 g/dm3 of the solution
So therefore, molarity in mol/dm3 = mol in g/dm3 / molar mass
Molarity = 172.81 g/dm3 / 78 g/mol
Molarity = 2.22 mol/dm3
The molarity of the solution is 2.22 mol/dm3
Answer:
The answer is 2.22mol
Explanation: