3rd 9 Wk 6 Wk Chemistry Review

To find the molecular formula from the empirical formula, one must determine the compound's ___________

• density

• structural formula

• mathamatical formula

• formula mass

A compound's empirical formula is C₂H₅. If the formula mass is 58 amu, what is the molecular formula?

In Chemistry, the​ (a)   is also known as Avogadro’s number that is equal to 6.02 x 10²³ and is a unit used for counting.

• mole
• formula
• percent composition
• density
• dimension analysis

The coefficients in a chemical equation are the ​ ​

​ (a)  

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

Tags

NGSS.MS-PS1-5

The mass of 0.36 moles of ethanoic acid, CH₃COOH is ​ (a)  

• 21.60 g
• 0.06g
• 36.00g
• 6.00g
• 25.92 g
• 166.67 g

Answer explanation

Any time yoyu see trhe word "mass" or "gram" you must calculate molar mass before you do any other calculations.

How many moles of gold are in 8.96 x 10²⁰ atoms of gold?

• 1.48 x 10⁴³ mol

• 1.49 x 10^-3 mol

• 672 mol

• 1.76 x 10²⁶ mol

• 4.64 x 10¹⁹ mol

Find the grams of silver, Ag, are in 0.0342 mol Ag. __ g Ag

Find the mol of silver, Ag, are in 342 g Ag __ mol Ag

Find the number of iron atoms are present in a piece of iron with a given mass of 95.8 g

Find the moles are in 41.6 g ammonium carbonate (NH₄)₂CO₃

__ mol (NH₄)₂CO₃

Tags

NGSS.HS-PS1-7