Answer:
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
Explanation:
It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.
But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.
When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.

Thus the correct option is (a).
Answer:
The answer is : D. Wind energy
Answer:
metal Atom
Explanation:
every transition metal atom are responsible for the flame color. Some metal are also confirmed by flame test.
Answer is: 2,0,0,±1/2.
1) n = 1. The principal quantum number (n) is one of four quantum numbers which are assigned to each electron in an atom to describe that electron's state.
2) l = 0. The azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital.
3) ml = 0. Magnetic quantum number specify orientation of electrons in magnetic field and number of electron states (orbitals) in subshells.
Magnetic quantum number (ml) specifies the orientation in space of an orbital of a given energy and shape . Magnetic quantum number divides the subshell into individual orbitals which hold the electrons, there are 2l+1 orbitals in each subshell.
4) The spin quantum number, ms, is the spin of the electron; ms = +1/2 or -1/2.