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Part 1)

One reaction that produces hydrogen gas can be represented by the unbalanced chemical equation- Mg(s) + HCl(aq) −→ MgCl2(aq) + H2(g).
What mass of HCl is consumed by the reaction of 3.15 mol of magnesium?
Answer in units of g.
Part 2) What mass of MgCl2 is produced? Answer in units of g.
Part 3) What mass of H2 is produced? Answer in units of g.

User Kgraney
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2 Answers

3 votes
Umm well this I do not know someone should know tho
User PraAnj
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4 votes

Answer:

Part 1: 229.95g

Part 2: 598.5g

Part 3: 12.6g

Step-by-step explanation:

Note: I learned this last week. Answer not sure.

Pls tell me if i got it right or wrong.

Mg + HCl - > MgCl2 + H2

First, balance the equation.

There is only 1 H and 1 Cl at the left side. BUT there are 2 Cl and 2 H at the right side. So you can add a 2 in front of HCl to balance it.

Mg + 2HCl - > MgCl2 + H2

Formula 1: (n= m/mr)

n = moles, m= mass, mr = molecular mass

Formula 2: (n= v/24)

v = volume

Part 1

What mass of HCl is consumed by the reaction of 3.15 mol of magnesium?

Ratio of

(look at the number in front of each)

2HCl : Mg

2 : 1

(3.15 x 2) : 3.15 moles

6.3 moles : 3.15 moles

So 2HCl has 6. 3 moles

Now use formula 1 (n = m/mr)

Calculate molecular mass of HCl

Check your periodic table

mr of HCl =(1 + 35.5) = 36.5

6.3 = m/36.5

m = 229. 95grams

Part 2

What mass of MgCl2 is produced? Answer in units of g.

Ratio of

2HCl : MgCl2

(1 +35.5) : (24+35.5x2)

36.5: 95

229.95g :?

229.95g : 598.5g

m = 598.5g

Part 3

What mass of H2 is produced? Answer in units of g.

2HCl : H2

36.5 : 2

229.95g :?

229.95g : 12.6g

m = 12.6g

User Kitesurfer
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