Question

Trisha and her lab partner were conducting a variety of experiments to produce gases: hydrogen, oxygen, and carbon dioxide. In one experiment, they added a piece of magnesium ribbon to 10 milliliters of hydrochloric acid. They observed bubbles being produced and did a variety of tests to identify the escaping gas; it proved to be hydrogen The reaction is represented by the following equation: Mg + 2HCl → MgCl2 + H2(g) Trisha and her lab partner filled a beaker with 150 milliliters of a 0.10 M HCl solution. How many moles of HCl are in the beaker? Remember, molarity = moles liter . A) 0.015 mol HCl B) 0.150 mol HCl C) 6.67 mol HCl D) 15 mol HCl

Answer 1

Given:

Volume of HCl = 150 ml

Molarity of HCl = 0.10 M

To determine:

The # moles of HCl

Explanation:

The molarity of a solution is the number of moles of a solute dissolved in a given volume

In this case:

Molarity of HCl = moles of HCl/volume of the solution

moles of HCl = Molarity * volume = 0.10 moles.L-1 * 0.150 L = 0.015 moles

Ans: A)

Moles of HCl is 0.015