Stoichiometry

When the limiting reactant in a chemical reaction is completely used, the

• reaction slows down
• reaction speeds up
• excess reactants begin combining
• reaction stops

If the percentage yield is equal to 100%, then

• the actual yield is greater than the theoretical yield
• the actual yield is less than the theoretical yield
• the actual yield is equal to the theoretical yield
• there was no limiting reactant

Tags

NGSS.HS-PS1-6

NGSS.HS-PS1-7

To determine the limiting reactant in a chemical reaction, one must know the

• amount of product formed
• available amount of one of the reactants
• available amount of each of each reactant
• speed of the reaction

Tags

NGSS.HS-PS1-7

The coefficients in a chemical equation represent the

• number of atoms in each compound in a reaction
• relative numbers of moles of reactants and products
• masses, in grams, of all reactants and products
• number of valence electrons involved in the reaction

Which reactant controls the amount of product formed in a chemical reaction?

• mole ratio
• composition reactant
• excess reactant
• limiting reactant

For the reaction represented by the equation 2Fe + O₂ → 2FeO, how many grams of iron(II) oxide are produced from 8.55 mol of iron in an excess of oxygen?

• 307 g
• 8.40 g
• 447 g
• 614 g

Tags

NGSS.HS-PS1-7

The actual yield of a chemical reaction is generally

• less than the theoretical yield
• equal to the theoretical yield
• greater than the theoretical yield
• greater than the percentage yield

Tags

NGSS.HS-PS1-7

What is the ratio of the actual yield to the theoretical yield, multiplied by 100%?

• Avogadro yield
• excess yield
• percentage yield
• mole ratio

For the reaction represented by the equation Pb(NO₃)₂ + 2 KI → PbI₂ + 2 KNO₃, how many moles of lead(II) iodide are produced from 239 g of potassium iodide and an excess of lead(II) nitrate?

• 1.44 mol
• 0.722 mol
• 1.44 mol
• 0.720 mol

Tags

NGSS.HS-PS1-7

In the equation 2KClO₃ → 2KCl + 3O₂, how many moles of oxygen are produced when 6.7 mol of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

Tags

NGSS.HS-PS1-7