Question

How many moles of Hydrogen gas will be produced if you start with 2.5 moles of Magnesium and an excess of Hydrochloric Acid given the following balanced chemical reaction:
Mg + 2HCl → MgCl2 + H2

Group of answer choices

A. 1.25 moles

B. 5.0 Moles

C. 7.5 moles

D. 2.5 moles

Answer 1

Answer:

D.) 2.5 moles

Explanation:

To find the moles of H₂, you need to multiply the given value by the mole-to-mole ratio. This ratio consists of the coefficients in front of the relevant molecules. It is important to arrange the ratio in a way that allows for the cancellation of units.

1 Mg + 2 HCl -----> MgCl₂ + 1 H₂
^                                            ^

2.5 moles Mg            1 moles H₂
-----------------------  x  ---------------------  =  2.5 moles H₂
                                   1 mole Mg