How many grams of hydrogen gas can be obtained from 0.373 grams of magnesium? note that the equation is not balanced. mg(s) + hcl(aq) → mgcl2(aq) + h2(g)

The first step to answering this item, is to balance first the chemical reaction. This is shown below.

      Mg(s) + 2HCl (aq) --> MgCl₂(aq) + H₂(g)

 

HCl is multiplied by 2 to equalize the number of the hydrogen and chlorine.

The molar masses of magnesium and hydrogen gas are 24.3 g and 2 g, respectively. Using dimensional analysis and conversions, mass of hydrogen is calculated through the equation,

 Mass of H₂ =    (0.373 g Mg)(1 mol Mg/24.3 g Mg)(1 mol H₂/ 1 mol Mg)(2 g H₂/1 mol H₂)

             Mass of hydrogen = 0.031 g of hydrogen

 

ANSWER: 0.031 g H₂

Electron equations of the given changes are as follow,a)                              cu      →      cu⁺²  + 2e⁻b)                              mg⁺²  +  2 e⁻      →      mgc)                              cl⁻    →      cl  +  1e⁻d)                              s  +  2 e⁻    →      s²⁻e)                                o²⁻      →      o  +  2 e⁻f)                              p  +  3 e⁻    →      p³⁻g)                              fe²⁺    →      fe³⁺  + 1 e⁻h)                              s²⁻    →      s⁴⁺  +  6 e⁻

Ive had this before. your answer would be d. hope this ya