Answer:
The answer is I think None.
Helium - 4 isotope has 2 protons and 2 neutrons.
Its atomic number is 2 (the number of protons). Atomic number is the number of protons in the atom of an element and it identifies the element. All the isotopes of an element have the same atomic number (same number of protons). So, all the isotopes of hellium have 2 protons.
The number 4 that identifies the helium - 4 isotope is the mass number, i.e. the number of protons plus the number of neutron. So, helium-4 isotope has 2 protons and 2 neutrons. While, other isotopes of helium have 2 protons but different number of neutrons.
The atomic number enable us to deduce the number of electrons in an atom because the atoms are neutral, which implies that the positive and negative charge are equal. Given that the magnitude of the charge of electons and protons are equal but the sign is opposed (protons are positve and electrons are negative) the number of electrons in the atom equals the number of protonts. That is why the atomic number is also the number of electrons of the atom.
Answer:
Because of less weight kick ball has more acceleration.
Explanation:
Acceleration of kick ball:
5 m/s
Acceleration of soccer ball:
3 m/s
Newton's second law:
According to newton's second law the acceleration of object depends upon two variables.
1) Mass of object
2) Force acting on it
Mathematical expression:
a = f/m
a = acceleration
f = force
m = mass
The force on balls are same thus the acceleration is depend upon the masses of balls.
The soccer ball has more weight that's why its acceleration is less while kick ball is lighter and thus its acceleration will more.
Answer:
Various limitations of Mendeleev's periodic table are:-
Position of hydrogen - he couldn't assign a correct position to hydrogen as it showed properties of both alkali and halogens .
Position of isotopes - he considered that the properties of elements are a function of their atomic masses. Hence isotopes of a same element couldn't be placed.
In the d-block , elements with lower atomic number were placed before higher atomic number.
Explanation:
Phosphate because it's the closest to sulfur on the periodic 2