How will you prepare hydrogen from zinc and dilute acid.

Step 1: Take a few grams of zinc granules and place them in a 500 mL flask.
Step 2: With the help of a thistle funnel, add dilute hydrochloric acid to the zinc granules. If hydrochloric acid isn’t available, dilute sulphuric acid can be used as an alternative.
Step 3: Hydrogen gas will be automatically collected with the help of a delivery tube via the downward displacement of water. This can be explained by the fact that hydrogen gas is lighter than water

The chemical reactions that take place during the preparation of hydrogen gas are:

General Format: Metal + Dilute Acid → Salt of Metal & Acid + Hydrogen
With Hydrochloric Acid: Zn + 2HCl → ZnCl2 + H2
With Sulphuric Acid: Zn + H2SO4 → ZnSO4 + H2

Hope this helped :)

Hydrogen is basically prepared by action of dilute acids On metals.
Dilute Hydro chloric acid is added To zinc granules. The hydrogen produced is then passed through anhydrous calcium chloride or concentrated sulphuric acid. The hydrogen collected by upward delivery because it is lighter than air. If the reaction is too slow Copper (II) Sulphate solution can be added to speed up the solution.
Zn (s)+ 2HCl (aq)———ZnCl2 (aq)+ H2(g).

Most likely a is the answer - because  you generate   38 atp's but also consume an atp.   each atp gives approx. less than 4 kcal so probably a is the closest answer.