Guided Reading and Study Workbook page on chemical reactions and balancing equations.

Let’s go step by step to make sure we understand and solve each part correctly.

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Question 9:
We are told:
Hydrochloric acid reacts with zinc → produces aqueous zinc(II) chloride + hydrogen gas.

From Table 11.1 (which we don’t have, but standard symbols apply):

- Hydrochloric acid = HCl(aq)
- Zinc = Zn(s)
- Zinc(II) chloride = ZnCl₂(aq) — because zinc is +2, chloride is -1, so need two Cl⁻
- Hydrogen gas = H₂(g)

So skeleton equation:

HCl(aq) + Zn(s) → ZnCl₂(aq) + H₂(g)

✔ This matches what’s already written in pink on the worksheet. So no correction needed here — it’s correct as given.

But note: this equation is not balanced yet. We’ll balance it later if asked — but question 9 only asks for the *skeleton* equation, which shows formulas and states, not necessarily balanced atoms.

So answer for #9 is already provided and correct.

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Question 10: What is the law of conservation of mass?

This is a definition.

In any physical or chemical change, matter cannot be created or destroyed — total mass before = total mass after.

The pink text says:
“In any physical or chemical change, mass is neither created nor destroyed.”

✔ That’s exactly right.

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Question 11: Complete the flowchart for balancing equations.

Let’s go box by box.

Box 1:
“Determine the correct formulas and physical states for the _________ and __________.”

→ You start by knowing what you’re reacting (reactants) and what you get (products).

Answer: reactants, products

✔ Already filled in pink — correct.

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Box 2:
“Write a _______________ with the formulas for the reactants on the left and the formulas for the products on the right of a yields sign (⟶).”

→ This is called a “skeleton equation” — unbalanced, just shows what reacts and what forms.

Answer: skeleton equation

✔ Already filled — correct.

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Box 3:
“Count the number of _______________ of each element in the reactants and in the products.”

→ To balance, you count how many atoms of each element are on each side.

Answer: atoms

✔ Already filled — correct.

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Box 4:
“Balance the number of atoms of the elements on the two sides of the equation by placing _______________ in front of formulas. Never try to balance an equation by changing the _______________ in formulas.”

→ You add coefficients (numbers in front) to balance. You NEVER change subscripts (those define the compound!).

Answer: coefficients, subscripts

✔ Already filled — correct.

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Box 5:
“Check each atom or polyatomic ion to be sure the equation is _______________, and make sure that all coefficients are in the _______________ possible ratio.”

→ After balancing, check that every element has same number on both sides → equation is balanced.

Also, coefficients should be smallest whole numbers → lowest possible ratio.

Answer: balanced, lowest

✔ Already filled — correct.

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Wait — actually, looking again at the image, ALL answers are already filled in pink! The student may have completed it already, or perhaps they want verification?

Since the user said “Solve the problem accurately”, and all blanks are already filled correctly in pink, then our job is to confirm everything is correct.

Let me double-check Box 4 wording:

> “Never try to balance an equation by changing the ________ in formulas.”

Yes — changing subscripts changes the identity of the compound. For example, H₂O vs H₂O₂ — totally different substances. So yes, never change subscripts.

And coefficients are multipliers in front — like 2H₂O means two water molecules.

All good.

Final confirmation: All answers shown in pink are scientifically accurate and match standard chemistry teaching.

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Final Answer:
All answers provided in the worksheet are correct. No corrections needed.