The atomic number is the simply the number of protons in the atom. So in the first row with atomic number 2, the number of protons is 2.
If the atom has no charge, which I think you can assume for all of these, the number of electrons is equal to the number of protons. So the number of electrons is also 2.
The number of neutrons (which are the particles with no charge in the nucleus) is simply the mass number minus the atomic number i.e. 4 - 2 = 2.
The isotopic symbol is the symbol which is found on the periodic table of elements. There are 2 numbers associated which each element on the table. The larger is the mass number and the smaller is the atomic number. The atomic number or number of protons is what identifies the element. Looking at the periodic table ( https://sciencenotes.org/wp-content/uploads/2015/01/PeriodicTableOfTheElementsBW.pdf or https://simple.wikipedia.org/wiki/Periodic_table_(big) ), it can be seen that the element on the first row above with an atomic number of 2 is Helium with a symbol He. The number that is included with the name is simply the mass number which is 4 in this case, which tells us that this type of helium has 2 neutrons.
Another type (or isotope) of helium is Helium-3 which has one neutron.
Try the next row and post back if you have trouble with it
Answer:
it is sooo easy u need to use magnetic panels on the rail and put the magnet on the train it works under the principal of magnetic
True because the atmosphere is in the way
Answer:
El área de la placa es aproximadamente 5102.752 centímetros cuadrados.
Explanation:
Asumamos que el cambio dimensional como consecuencia de la temperatura es pequeña, entonces podemos estimar el área de la placa de cobre en función de la temperatura mediante la siguiente aproximación:
![A_{f} = w\cdot l \cdot [1 + 2\cdot \alpha\cdot (T_{f}-T_{o})]](https://tex.z-dn.net/?f=A_%7Bf%7D%20%3D%20w%5Ccdot%20l%20%5Ccdot%20%5B1%20%2B%202%5Ccdot%20%5Calpha%5Ccdot%20%28T_%7Bf%7D-T_%7Bo%7D%29%5D)
(1)
Donde:
- Ancho de la placa, en centímetros.
- Longitud de la placa, en centímetros.
- Coeficiente de dilatación, en 
.
- Temperatura inicial, en grados Celsius.
- Temperatura final, en grados Celsius.
Si sabemos que 
, 
, 
, 
and 
, entonces el área de la placa a la temperatura final:
![A_{f} = (65\,cm)\cdot (78\,cm)\cdot \left[1+\left(17\times 10^{-6}\,\frac{1}{^{\circ}C} \right)\cdot (400\,^{\circ}C-20\,^{\circ}C)\right]](https://tex.z-dn.net/?f=A_%7Bf%7D%20%3D%20%2865%5C%2Ccm%29%5Ccdot%20%2878%5C%2Ccm%29%5Ccdot%20%5Cleft%5B1%2B%5Cleft%2817%5Ctimes%2010%5E%7B-6%7D%5C%2C%5Cfrac%7B1%7D%7B%5E%7B%5Ccirc%7DC%7D%20%5Cright%29%5Ccdot%20%28400%5C%2C%5E%7B%5Ccirc%7DC-20%5C%2C%5E%7B%5Ccirc%7DC%29%5Cright%5D)
El área de la placa es aproximadamente 5102.752 centímetros cuadrados.
Solving for vf gives you PiVi/Pf. Now plug in 101kPa*10L/43kPa = 23.48L. Using significant figures i would round to 23.5L
