Mathematics of Molecules Assessment

A formula with the lowest whole # ratio of elements in a compound is called

• Molecular Formula
• Chemical Formula
• Empirical Formula 
• Distance Formula

How many molecules are in 2.5 mol of NaCl?

• 1.5 x 10²⁴ molecules

• 1.5 molecules

• 4.15 molecules

• 1.5 x 10²³ molecules

Which pair has the same empirical formula?

• NaCrO₄ and Na₂Cr₂O₇
• C₂H₄O₂ and C₆H₁₂O₆
• C₃H₆O₃ and C₂H₆O₂
• CH₄ and C₂H₆

diphosphorus pentoxide

• P₂O₅
• PO₅
• P₅O₂
• P₂O₆

Tags

NGSS.MS-PS1-1

T/F
If 2 compounds have the same empirical formula, they are the same (same properties, structure, etc.)

• True
• False

What is the empirical formula for the following molecular formula: C₅H₁₂

• C₅H₁₂
• CH₃
• CH₂
• C_2.5H₆

What is the empirical formula of a substance with the molecular formula C₂H₄?

• C₂H₂

• C₂H₂

• C₁H₁

• CH₂

Tags

NGSS.MS-PS1-1

What is the empirical formula of a substance with the molecular formula NaCl?

• Na₂Cl

• NaCl₂

• NaCl

• Na₂Cl₂

What is the empirical formula for hydrogen peroxide (H₂O₂)?

• H₂O

• H₂O₂

• HO

• HO₂

What is the percent by mass of magnesium in MgO?

• 20%
• 40%
• 50%
• 60%