The groups (left to right) are numbered from 1 to 18. they arent numbered any other way.
period (up to down.) are numbered from 1-7
Answer:
My bad i didnt mean to put that carry on.
Explanation:
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).
The region is located on an active oceanic plate
B. The surface of a silver cup turns black when it is exposed to air.