Answer:
1) 72 mole
2)1152 mole
3)256 mole
4) 2890 mole
Explanation:
very important for u
number of mole= given mass/molecular mass
symbolically : n= m/Mm
1) first atomic mass (carbon =12)
n=6gram × 12gram /mole
n=72mole
2) atomic mass (Magnesium =24)
48 gram × 24 gram /mole
n= 1152 mole
3)atomic mass (oxygen = 16×2=32
n= 8 gram × 32 gram/ mole
n= 256mole
4) atomic mass ( Nitrogen =14 , hydrogen = 1×3
14+3=17
n= 170 gram × 17 gram / mole.
n= 2890 mole
It is rinsed with ionised water to remove any impurities that may be present
Calculate first the number of moles of ethylene glycol by dividing the mass by the molar mass.
n = (6.21 g ethylene glycol) / 62.1 g/mol
n = 0.1 mol
Then, calculate the molality by dividing the number of moles by the mass of water (in kg).
m = 0.1 mol/ (0.025 kg) = 4m
Then, use the equation,
Tb,f = Tb,i + (kb)(m)
Substituting the known values,
Tb,f = 100°C + (0.512°C.kg/mol)(4 mol/kg)
<em>Tb,f = 102.048°C</em>
The answer: less frequency, causing the pitch to be lowered.
This is known as the Doppler effect. When you have an object that is producing sound while moving, the side that it is moving towards to will have waves that will become a bit more squished together, while the other side that it is moving away from will have waves that are spaced a bit more apart from each other. The only determining factor in this is the magnitude of the speed, so the faster the object is moving towards or away from you, then the more severe pitch change the object will have.
In this case, it's just asking in general what would happen if the horn was moving away from you while it was giving off sound waves. Therefore, since it is moving away from you, its sound waves are a bit further apart, resulting in a lowered frequency and pitch.