Hydrochloric acid reacts with metals to produce hydrogen gas according to the equation shown below. How many grams of a metal (X) will be
consumed in a reaction if 49.0 mL of 3.0 M HCl are used? The molar mass
of the metal (X) is 72.55 g/mol. Report your answer to the nearest tenth.
2 HCl + X --> XCl2 + H2

5.33g of X will be consumed

Explanation:

Based on the reaction, 2 moles of HCl reacts per mole of the metal. To solve this question we must find, as first, the moles of HCl that reacted. With these moles and the chemical equation we can find the moles of X and its mass (With molar mass) as follows:

Moles HCl:

49.0mL = 0.0490L * (3.0mol / L) = 0.147 moles HCl

Moles X:

0.147 moles HCl * (1mol X / 2mol HCl) = 0.0735 moles X

Mass X:

0.0735 moles X * (72.55g / mol) =

the answer is na (sodium)