Test 5.1 Review

When does a reaction stop?

• When it wants to
• When both the limiting and excess reactants are gone
• When all the excess reactant has been consumed
• When all the limiting reactant has been consumed

Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.

• 1.16%
• 116%
• 85%
• 76%

Tags

NGSS.HS-PS1-7

The limiting reactant

• slows the reaction down

• runs out first during the course of a reaction

• is the reactant that is left over

• controls the speed of the reaction

2H_{2 +} O₂ --> 2H₂O

After the reaction:

Mass of H₂ = 0g

Mass of O₂ = 3.5g

Mass of H₂O = 5.0g

Which is the limiting reactant?

• H₂

• O₂

• H₂O

When reacting Na with Cl₂, we calculated that the theoretical yield should be 13.0 grams. Our actual yield was 12.5 grams. What is the percent yield?

• 100%

• 104%

• 96%

• 0.96

Zn + 2HCl → ZnCl​₂ ​​+ H​₂​​
15 grams of HCl should theoretically produce 0.42 grams of H₂. The reaction actually produced 0.15 grams of H₂. What is the percent yield of H₂?

• 2.8%
• 280%
• 1%
• 36%

Tags

NGSS.HS-PS1-7

Use the equation 2 Al + 3 Cl₂ ---> 2 AlCl₃. If 2 moles of aluminum and 2 moles of chlorine are reacted to produce AlCl₃, identify the limiting reactant.

• AlCl3

• Cl2

• Al

Zn  +  CuCl​₂​​  →  ZnCl​₂​  ​+  Cu
How many grams of ZnCl₂ will be produced from 23.0 g of Zn

• 0.354 moles
• 1495 moles
• 47.76 g

Tags

NGSS.HS-PS1-7

P₄ + 6Cl₂ --> 4PCl₃

The reaction of 75 moles P₄ with excess chlorine gas produces 110 moles PCl₃ in lab. Find the theoretical yield and calculate percent yield for the reaction.

• 78%

• 64%

• 27%

• 37%

2H₂  +   O₂  →  2H₂O
How many moles of oxygen are consumed if 8 moles H₂ are used?

• 2
• 4
• 6
• 8

Tags

NGSS.HS-PS1-7