Answer:
ELEMENTS
Explanation:
CUZ AN A
ELEMENT IS A GROUP OF ATOMS THAT CANNOT BE BROKEN DOWN BY ANY CHEMICAL OR PHYSICAL MEAN
Because Electrons have a negative charge
The mass number is the summation of number of proton and neutron present in a nucleus of an atom. For the neutral atom the number of positive charge (number of proton) must be equal to the number of electrons. The number of electrons present in an atom is the atomic number of the atom. The standard way to express the mass number (a) and atomic number (m) of a atom (say X) is
. Now for silicon number of electron or atomic number is 14. And the mass number (a) given 29. Thus the expression nucleus of silicon will be 
Molarity is simply the ratio of the number of moles of a
substance over the total volume of the solution. Assuming that the addition of
0.850 moles does not change the overall volume of 1.70 L, therefore molarity is
simply:
Molarity = 0.850 moles / 1.70 L = 0.5 moles / L = 0.5 M
The liquid will stop converting into vapor. This process is to balanced the amount of substance of both phases inside the flask.