Answer:
0.17%
Explanation:
With the equation:
2Cr2O7 2- + C2H5OH + H2O --> 4Cr3+ + 2CO2 + 11H2O
We can assume that every mole of ethanol needs 2 moles of Dichromate to react.
So if in 1L we have 0.05961 moles of dichromate we can discover how many moles we have in 35.46mL
1000 mL - 0.05962 moles
35.46 mL - x
x = 
x = 2,11* 10^-3 moles
As we said earlier, 1 mole of ethanol needs 2 mole of dichromate, so in the solution we have 1,055*10^-3 moles of ethanol. We can discover the mass of ethanol present in the solution.
1 mole - 46g
1.055*10^-3 - y
y = 46 * 1.055*10^-3
y = 0.048 g
To discover the percent of alchol we can use a simple relation
28 g - 100%
0.048 - z
z = 
z = 0.17%
<span>2.10 grams.
The balanced equation for the reaction is
CO + 2H2 ==> CH3OH
The key thing to take from this equation is that it takes 2 hydrogen molecules per carbon monoxide molecule for this reaction. And since we've been given an equal number of molecules for each reactant, the limiting reactant will be hydrogen.
We can effectively claim that we have 5.86/2 = 2.93 l of hydrogen and an excess of CO to consume all of the hydrogen. So the number of moles of hydrogen gas we have is:
2.93 l / 22.4 l/mol = 0.130803571 mol
And since it takes 2 moles of hydrogen gas to make 1 mole of methanol, divide by 2, getting.
0.130803571 mol / 2 = 0.065401786 mol
Now we just need to multiply the number of moles of methanol by its molar mass. First lookup the atomic weights involved.
Atomic weight carbon = 12.0107 g/mol
Atomic weight hydrogen = 1.00794 g/mol
Atomic weight oxygen = 15.999 g/mol
Molar mass CH3OH = 12.0107 + 4 * 1.00794 + 15.999 = 32.04146 g/mol
So the mass produced is
32.04146 g/mol * 0.065401786 mol = 2.095568701 g
And of course, properly round the answer to 3 significant digits, giving 2.10 grams.</span>
Answer:
d) A - 70% B - 30%
Explanation:
If x is the abundance of A, and 1−x is the abundance of B, then:
x (32.0) + (1−x) (33.0) = 32.3
32x + 33 − 33x = 32.3
33 − x = 32.3
x = 0.7
The abundance of A is 70%, and the abundance of B is 30%.
The best answer is C
Since identical atoms would have the same electronegativity, thus making its electronegativity difference close to zero, if not equal to zero (O), making the bond between the two to be covalent. Thus, a chemical bond formed between two identical atoms is a covalent bond.
