3 Quarter EOM Review CP

When does a chemical reaction stop?

• When the lab is finished
• When the excess reactant is used up
• When the limiting reactant is used up
• Chemical reactions never stop

What is a Excess Reagent?

• amount you end with
• what you run out of first
• what you have left over
• what you start with

If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the

• theoretical yield
• mole ratio
• actual yield
• percentage yield

Tags

NGSS.HS-PS1-7

Using the following equation:
Fe₂O₃(s) + 3H₂(g) → 2Fe(s) + 3H₂O(l)
How many moles of iron can be made from  6 moles H₂? 

• 4 moles Fe
• 6 moles Fe
• 9 moles Fe
• 2 moles Fe

Tags

NGSS.HS-PS1-7

9. Complete the equation for the percent yield of a chemical reaction:
Percent yield=(________)÷(________)×100%

• actual yield; theoretical yield
• theoretical yield; actual yield

How many moles of magnesium are in 3.01x10²² atoms of magnesium?

• 5.00x10⁴⁴ moles Mg
• 0.050 moles Mg
• 1.81x10⁴⁶ moles Mg
• 5 moles Mg

What is the mole ratio of oxygen gas to water?

2 H₂ + O₂ → 2 H₂O

• 1:2

• 3:4

• 4:3

Calculate the molar mass of propane

C₃H₈

• 13 g/mol

• 44 g/mol

• 99 g/mol

How many grams of magnesium chloride are produced if 4.67 moles of HCl react?

Mg + 2 HCl --> MgCl₂ + H₂

• 222 g MgCl₂

• 4.67 g MgCl₂

• 94 g MgCl₂

Tags

NGSS.HS-PS1-7

You are given the following percentages: 40.05% S and 59.95% O. Find the empirical formula for these elements.

• SO
• SO2
• SO3
• SO4