Chemistry

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A mixture of chromium and zinc weighing .362 g was reacted with an excess of hydrochloric acid.
After all the metals in the mixture reacted 225 mL of dry hydrogen gas was collected at 27 C and 750 torr.
Determine the mass percent Zn in the metal sample. [Zinc reacts with hydrochloric acid to produce zinc chloride and hydrogen gas;
chromium reacts with hydrochloric acid to produce chromium (III) chloride and hydrogen gas.]

What steps should i take to solve this?

Calculate the amount of H2 gas from the zinc reaction, subtract that from the amount collected. THen, that amount must have come from the chronium reaction, calcualte the amount of chromium used.

Finally, calculate the mass percent of zinc.

is the percent of zinc 41.668% ?

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