These are my lab notes: I added 10 mL of water to the flask. I added 10 mL of 6M

Question

These are my lab notes:

I added 10 mL of water to the flask. I added 10 mL of 6M hydrochloric acid to the flask. I closed the flask. The temperature was 21.5. The pressure was 1.00. The volume of the liquid is 20, so the gas is 130. I put .1 g of magnesium into flask. The pressure went to 1.83 and dropped to 1.76. The temperature went to 34.7 and dropped to 21.6 The volume of the gas is 130.1. After inserting the gas syringe, the volume of the gas in the syringe was 99.5. The new temperature was 21.5. The new pressure was 1.00. The final liquid volume in the flask is 19.9.

1. Which of the following represents the balanced chemical equation for this reaction? A.Mg + HCl -> H2 + MgCl2 B.Mg + 2HCl -> H2 + MgCl2 C.Mg + 2HCl -> H2 + 2MgCl2 D.2Mg + 2HCl -> H2 + MgCl2

2. How many moles of magnesium are consumed for every mole of hydrogen gas produced? Choose the closest answer. A.2 mol B.1.5 mol C.1 mol D.0.5 mol

3. Suppose magnesium is the limiting reagent, which of the following chemicals will be found in the flask after the completion of the reaction? A.hydrochloric acid B.magnesium hydride C.magnesium D.hydrofluoric acid

4. Addition of which of the following reagents would lead to the formation of more hydrogen gas? A.hydrochloric acid B.magnesium chloride C.hydrogen D.magnesium

5. Suppose that sulfuric acid (H2SO4) was added instead of hydrochloric acid. What would you expect to find in solution at the end of the reaction? A.magnesium (Mg) B.hydrochloric acid (HCl) C.magnesium sulfate (MgSO4) D.magnesium chloride (MgCl2)

6. How many molecules are there in 1 mole of a substance? A.3.141 × 1022 molecules B.5.217 × 1022 molecules C.6.022 × 1023 molecules D.1 molecule

Explanation / Answer

1. Which of the following represents the balanced chemical equation for this reaction?

A.Mg + HCl -> H2 + MgCl2

B.Mg + 2HCl -> H2 + MgCl2

C.Mg + 2HCl -> H2 + 2MgCl2

D.2Mg + 2HCl -> H2 + MgCl2

Note that... Mg is always+2 charged...

H is +1 and Cl is -1; then expect:

MgCl2 and H2 formation

ratio is clearly 1:2:2so Mg(s) + 2HCl(aq) --> MgCl2(aq) + H2(g)

2. How many moles of magnesium are consumed for every mole of hydrogen gas produced? Choose the closest answer.

A.2 mol

B.1.5 mol

C.1 mol

D.0.5 mol

from the ratio, 1 mol of MG reacts per 1 mol of H2(g) produced

so 1:1 ratio, i.e. 1

3. Suppose magnesium is the limiting reagent, which of the following chemicals will be found in the flask after the completion of the reaction?

A.hydrochloric acid

B.magnesium hydride

C.magnesium

D.hydrofluoric acid

choose HCl, since it is in excess, so it will not react completely, Mg is limiting, so it will finish all

4. Addition of which of the following reagents would lead to the formation of more hydrogen gas?

A.hydrochloric acid

B.magnesium chloride

C.hydrogen

D.magnesium

From the previous example, addition of Magnesium, th elimting reactant, will increase H2(g) formation

5. Suppose that sulfuric acid (H2SO4) was added instead of hydrochloric acid. What would you expect to find in solution at the end of the reaction?

A.magnesium (Mg)

B.hydrochloric acid (HCl)

C.magnesium sulfate (MgSO4)

D.magnesium chloride (MgCl2)

Cl will not exist, so SO4-2 are readily available, Mg+2 and OS4-2 pair each toher to form MgSO4

6. How many molecules are there in 1 mole of a substance?

A.3.141 × 1022 molecules

B.5.217 × 1022 molecules

C.6.022 × 1023 molecules

D.1 molecule

According to avogrado's law/number... C.6.022 × 10^23 molecules

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