Mendeleev's arrangement of the periodic table was in order of increasing . A. atomic number
B. atomic mass
C. neutron number
D. valence electron number

B. atomic mass

Explanation:

He arranged the elements into rows in order of increasing mass so that elements with similar properties were in the same column.

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

answer seismograph;