In: Chemistry
1) All samples of a given compound, regardless of their source or how they were prepared, have the same proportions of their constituent elements. Which law does this refer to?
2) Determine the number of protons, neutrons and electrons in (65-top) (29-bottom)X
3) What species is represented by the information: p+ = 47 n
9)Let's assume we have 100 grams of the first
compound.
This would mean that we have:
52.14 g Carbon
34.73 g Oxygen
and
100 g - (52.14 + 34.73 g) = 13.13 g Hydrogen
13.13 g Hydrogen * (1 mol hydrogen/ 1.01 g hydrogen) = 13 mol
H
32.73 g Oxygen * (1 mol oxygen / 16.0 g oxygen) = 2.05 mol O
52.14 g Carbon * (1 mol carbon/12.01 g carbon) = 4.34 mol C
There is the least amount of oxygen. So lets divide each of the
numbers by that number
13 mol H/2.05 = 6 H
2.05 mol O/2.05 = 1 O
4.34 mol C/2.05 = 2 C
C2H60 = empirical formula
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First we must find the empirical formula.
70.79 g C * (1 mol C/12.01 g C) = 5.89 mol C
8.91 g H * (1 mol/1.01 g H) = 8.82 mol H
4.59 g N * (1 mol/ 14.0 g N) = 0.328 mol N
15.72 g O * (1 mol/16.0 g O) = 0.983 mol O
5.89 mol C/0.328 = 18 C
8.82 mol H/0.328 = 27 H
0.328 mol N/0.328 = 1 N
0.983 mol O/0.328 = 3 O
C18H27O3N = empirical formula
8)4.78 E23 formula units * 1mole/6.02 E23 * 1000 m moles/mole = 794 milimoles
5) RAM = The sum of (% abundance x isotopic mass of each
isotope). We shall use the symbol y to denote the isotope mass of
the other isotope.
Gallium has two isotopes. We are told that one is present in 60.11
% abundance, therefore the other is present in 100 - 60.11 = 39.89
% abundance.
RAM = 69.723 = [(68.926 x 0.6011) + (y x 0.3989)]
Solve for y ------> 69.723 = [41.4314 + 0.3989y]
Subtract 41.4314 from each side
69.723 - 41.4314 = 41.4314 - 41.4314 + 0.3989y
28.2916 = 0.3989y
Divide by 0.3989 each side
(28.363/0.3989) = (0.3989/0.3989) x y
1 y = 70.924 amu
1.law of definite proportion
2) n0. of protons = 29
electrons = 29
neutrons = mass no - 29 = 65 - 29 = 36
3) Ag +
4) E is false . it gives (-) 1 ions
6) tin(iv) sulfate
7) chloric acid
10.chloroacetone