Answer:
Six C atoms (C₆); five H atoms (H₅); one N atom (N); no O atoms
Explanation:
The rule of 13 states that the formula of a compound is a multiple n of 13 (the molar mass of CH) plus a remainder r.
MF = CₙHₙ₊ᵣ
Y has a molecular mass of 91 u
91/13 =7r0
The formula can't be C₇H₇ because a hydrocarbon must have an even number of H atoms,
The odd mass and the odd number of H atoms make it reasonable to add an N atom and subtract CH₂ (CH₂ = 14):
C₇H₇ + N - CH₂ = C₆H₅N
Check:
6C = 6 × 12.000 = 72.000 u
5H = 5 × 1.008 = 5.040
1N = 1 × 14.003 = <u>14.003 </u>
TOTAL = 91.043 u
This is excellent agreement with the observed mass of 91.0425 u.
There are six C atoms (C₆)
There are five H atoms (H₅)
There is one N atom (N)
There are no O atoms.
I took the test and the answer is chronium
<span>The average speed of the gas is related to the kinetic
energy of the gas. The kinetic energy of
the gas is also related to the temperature of the gas. If the average speed of
the gas is closer to zero, it means that it has very low motion or kinetic
energy. This can be inferred that the gas has a very low temperature. At absolute
zero, the motion of all the gas molecules stops. This means that the kinetic
energy of the gas is also zero. Zero kinetic energy means zero average speed.</span>
<span>So, the answer is cylinder B. The average speed of the gas
in cylinder B is closest to zero.</span>