Moles and Grams Stoichiometry

How many moles are in 19.82 g Mg?

• 1.226 mol Mg

• 481.7 mol Mg

• 1.000 mol Mg

• 0.82 mol Mg

Using the balanced equation below, calculate how many moles of carbon dioxide are produced from the combustion of 110 g of CH₄?

CH₄ + 2O₂ → CO₂ + 2H₂O

• 13.7 mol

• 2.75 mol

• 6.11 mol

• 6.85 mol

Using the balanced equation below, how many grams of H₂O will be produced from 150 grams of Fe₂O₃?

Fe₂O₃ + 3H₂ → 2Fe + 3H₂O

• 50 grams H₂O

• 60 grams H₂O

• 5000 grams H₂O

• 6000 grams H₂O

Tags

NGSS.HS-PS1-7

What is the first thing you must do to solve a stoichiometry problem?

• Balance the chemical equation.

• Record yourself singing Kumbaya and send it to your teacher because she loves music and actually likes that song.

• Text your friends and tell them you cannot believe your teacher would make you do such a hard assignment.

• Not even try to solve the problem so your teacher can guess what you don't understand about stoichiometry.

If 12.00 moles of NaClO₃ will produce how many grams of O₂?

NaClO₃ (s) → NaCl (s) + O₂ (g)

• After balancing the equation, 256 g of O₂, would be produced.

• After balancing the equation, 576 g of O₂, would be produced.

• After balancing the equation, 288 g O₂, would be produced.

• After balancing the equation, 942 g of O₂, would be produced.

How many grams of potassium chloride (KCl) can be produced from 356 g of potassium bromide (KBr)?

Cl₂ + KBr → Br₂ + KCl

(HINT: Don't forget to do STEP 1!)

• 749 g

• 223 g

• 479 g

• 814 g

REVIEW: How many grams are in 7.8 moles of NaCl?

• 476 grams

• 460 grams

• 456 grams

• 462 grams

REVIEW: How many grams are in 5.8 moles of calcium hydroxide?

(HINT: You were taught polyatomic ions!)

• 430 grams of calcium hydroxide

• 331 grams of calcium hydroxide

• 385 grams of calcium hydroxide

• 462 grams of calcium hydroxide

Tags

NGSS.HS-PS1-7

Given the following equation:

2K + Cl₂ → 2KCl,

how many grams of KCl (74.55 g/mol) is produced from 2.50 moles of K?

• 186.38 grams of potassium chloride

• 372.75 grams of potassium chloride

• 559.13 grams of potassium chloride

• 687.60 grams of potassium chloride

Tags

NGSS.HS-PS1-7

REVIEW: Balance this decomposition chemical equation.

AlCl₃ → Al + Cl₂

• 2AlCl₃ → 2Al + 3Cl₂

• 4AlCl₃ → 4Al + 6Cl₂

• 2AlCl₃ → Al + 3Cl₂

• AlCl₃ → 2Al + 6Cl₂

Tags

NGSS.HS-PS1-7