Please answer this question ASAP Salts of metals can be prepared by reacting a metal with an acid to produce the
salt and the gas hydrogen. Describe the test to show that the gas is hydrogen.
(2 marks)

put a test tube over the opening, remove it and quickly put a lit splint near the mout or in the tube. if you hear a squeaky pop it is hydrogen.

Explanation:

hydrogen ignites in air.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.