Stoich 1 2022-23 - CP

Conceptual

100

All of these are empirical formulas EXCEPT: 

a) C₂HO₂

b) MgCl₂

c) N₂S₃

d) C₃O₆

d) C₃O₆

empirical = fully simplified

200

Which of the following statements is FALSE about a mole... 

a) 1 mol = 6.022 x 10 23 things

b) 1 mol = molar mass of a substance 

c) 1 mol = 1 gram

d) Moles are used to count small things like atoms, molecules, particles, and formula units.

C is false

300

Which of these are conversion factors that you can use in stoichiometry?
a) 1 mol = 6.022 x 10²³ atoms

b) 1 mol = 1 gram

c) 1 mol = molar mass (grams)

d) Both A and C

d) Both A and C

400

Ella wants to convert grams of Na to moles. What must go at the bottom of the conversion factor she uses?

a) 1 mol

b) 1 gram

c) 22.99 grams

d) 6.022 x 10²³ atoms

c) 22.99 grams

Convert

100

How many moles is 5.19 x 10²⁴ atoms of Titanium (Ti)?

Round to the nearest 0.1 and include the correct unit and substance formula.

8.6 mol Ti

200

How many moles is in 32.89 grams of fluorine gas (F₂)? Round to the nearest 0.01 include the correct unit and substance.

0.87 mol F2

300

How many grams is 2.09 moles of Mercury Oxide whose formula is HgO₂?

Round to the nearest 0.1 include the correct unit and substance.

486.1 g HgO₂

400

Sally has a sample of 40.12 grams of silver (Ag). How many atoms of silver is this? Round to the nearest 0.01 include the correct unit and substance.

2.24 x 10²³ atoms Ag

Formulas

100

500 POINTS:  

Convert 1.25 x 10²⁴ atoms of nitrogen(N) to grams

Round to the nearest 0.01 include the correct unit and substance.

29.08 g N

Number 8

https://docs.google.com/document/d/1SYidrURPWl_D_CXuHA6BEv-vdkNTC6ZEIXFg4vozR_I/edit?usp=sharing

200

The molecular formula for a substance is C₄H₆O₂. What is the empirical formula for this substance?

C₂H₃O

300

What is the empirical formula for a substance that is 15.8 % carbon and 84.2 % sulfur?

CS₂

400

 What is the empirical formula for a substance with 83.60 % carbon and 16.40 % hydrogen by mass?

C₃H₇

Mass

100

What is the molar mass of CO₂ 

INCLUDE THE CORRECT UNIT FOR POINTS

44.01 g/mol 

12.01 + 16.00(2)

200

What is the molar mass of Mg(NO₃)₂

INCLUDE THE CORRECT UNIT FOR POINTS

148.33 g/mol

24.31 + 14.01(2) + 16.00(6)

300

What is the percent by mass of sodium in NaCl? 

Round to the nearest 0.1 and include the correct unit and substance.

39.3 % Na

400

What is the percent composition of aluminum in Al₂S₃?

Round to the nearest 0.1 and include the correct unit and substance.

35.9 % Al