Question

determine the excess reactant and calculate the mass of the remaining excess reactant after 12.5 grams of zn and 14.2 grams of hcl react. zn(s) 2 hcl(aq) ? zncl2(aq) h2(g)

Answer 1

To determine the excess reactant and calculate the mass of the remaining excess reactant, you need to first calculate the limiting reactant. Compare the moles of each reactant to the stoichiometric ratio in the balanced chemical equation. After identifying the limiting reactant, subtract the moles of the limiting reactant that react from the moles of the excess reactant initially present and then convert the result to grams using the molar mass of the excess reactant.

Step-by-step explanation:

In order to determine the excess reactant and calculate the mass of the remaining excess reactant, we need to first calculate the limiting reactant. This can be done by comparing the amount (in moles) of each reactant to the stoichiometric ratio of the balanced chemical equation.

Let's start by calculating the amount (in moles) of zinc (Zn) and hydrochloric acid (HCl) using their respective masses and molar masses. We have 12.5 grams of Zn and 14.2 grams of HCl.

Zn: moles = 12.5g Zn x (1 mole Zn / molar mass Zn)

HCl: moles = 14.2g HCl x (1 mole HCl / molar mass HCl)

Next, we compare the moles of Zn and HCl to the stoichiometric ratio of the balanced equation (1 mole Zn : 2 moles HCl). Whichever reactant produces fewer moles of product is the limiting reactant.

After identifying the limiting reactant, we can calculate the amount (in moles) and mass of the excess reactant that will be left over. This can be done by subtracting the moles of the limiting reactant that will react from the moles of the excess reactant originally present, and then converting the moles to grams using the molar mass.

Mass of excess reactant remaining = (moles of excess reactant initially present - moles of limiting reactant that react) x molar mass of excess reactant

Answer 2

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Step-by-step explanation:

In Chapter 6, the protagonist's internal struggles are vividly portrayed as they navigate personal dilemmas, seeking identity and purpose. Themes of resilience and determination emerge as they confront obstacles. Chapter 7 propels the storyline, unraveling unforeseen truths and building tension. The protagonist grapples with profound revelations, shaping their path significantly. These chapters collectively highlight character development and crucial plot progression, underscoring the novel's depth and thematic complexity.