On a cold day, the speed of sound in air is 330 m/s. A note with a frequency of 1,320 Hz is played on an instrument. What is the
1 answer:
You might be interested in
Answer:
The correct answer is option A: they are isotopes.
Explanation:
From atom X we know that the number of protons is 7 and the number of neutrons is 7 and from atom Z we know that the number of protons is 7 and the number of neutrons is 8.
Since the number of protons of atom X and atom Z is the same, we have that atom X and atom Z is the same element. The difference in the number of neutrons tells us that atom X and atom Z are isotopes. Remember that an isotope is one element that has atoms with different numbers of neutrons.
The mass number is given by:
Where <em>n</em> is the number of neutrons and <em>p </em>is the number of protons.
For atom X and atom Z we have:
Hence, they have a different mass number.
We know that the element with 7 protons is nitrogen. The first isotope is and the second isotope is
. Both isotopes are stables (they are not radioactive).
Therefore, the correct answer is option A: they are isotopes.
I hope it helps you!
Answer:
160790 J
Explanation:
We can find the heat necessary for the ice to go from -20 degrees Celsius to 0 degrees Celsius:
Where is the specific heat of ice, that is the amount of heat that must be supplied per unit mass to raise its temperature in a unit.
We must calculate the latent heat of fusion required for this ice mass to change to water:
Where H=334 J/g is the specific latent heat of fusion of water, that is the amount of energy needed per unit mass of a substance at its melting point to change from the solid to the liquid state.
Then we calculate the heat necessary for the water to go from 0 degrees Celsius to 20 degrees Celsius:
Where is the specific heat of water, that is the amount of heat that must be supplied per unit mass to raise its temperature in a unit.
Finally the 3 results are added: