Stoichiometry Unit A

Balancing Equations

100

Balance this equation.

__Na + __Cl₂ ---> __NaCl

2, 1, 2

200

Balance this equation.

__HF + __CaBr₂ ----> __HBr + __CaF₂

2, 1, 2, 1

300

Balance this equation.

__AlCl₃ + __Na₃N ---> __AlN + __NaCl

1, 1, 1, 3

400

Balance this equation. 

__MgCl₂ + __Na₃B ---> __Mg₃B₂ + __NaCl

3, 2, 1, 6

500

Balance this equation.

__NaO + __N₂ ----> __Na₃N + __O₂

6, 1, 2, 3

Moles --> Grams & Grams --> Moles

100

How many grams are in 5 moles of CO₂?

220 grams

200

How many grams are in 3 moles of NaCl? 

174 grams

300

How many moles are in 816 grams of Na₂S? Give an answer one place behind the decimal.

10.5 moles

400

How many moles are in 75 grams of H₂O? Give an answer one place behind the decimal.

4.2 moles

500

How many grams are in 25 moles of LiF?

650 grams 

Moles --> Atoms & Atoms --> Moles

100

How many moles are in (5.0 x 10²³) atoms of Sulfur (S)? Give an answer one place behind the decimal.

0.8 moles

200

How many moles are in (7.4 x 10²³) atoms of Nitrogen (N)? Give an answer one place behind the decimal.

1.2 moles

300

How many moles are in (8.2 x 10²⁴) atoms of Chlorine (Cl)? Give an answer one place behind the decimal.

13.6 moles

400

How many atoms are in 14 moles of MgCl₂? Give an answer one place behind the decimal.

(8.4 x 10²⁴) atoms

500

How many atoms are in 25 moles of KCl? Give an answer one place behind the decimal.

(1.5 x 10²⁵) atoms

Grams-->Moles-->Atoms &Atoms -->Moles--> Grams

100

If you have 56 grams of NaCl, how many atoms is that? Give an answer one place behind the decimal.

(5.8 x 10²³) atoms

200

If you have 145 grams of AlCl₃ how many atoms is this? Give an answer one place behind the decimal.

(6.6 x 10²³) atoms

300

If you have 1.02 x 10²³ atoms of MgF_2, How many grams is that? Give an answer one place behind the decimal.

10.5 grams

400

If you have (4.22 x 10²⁵) atoms of Na₂S, how many grams is that? Give an answer one place behind the decimal.

5467.8 grams

500

If you have 85 grams of H₂O, how many atoms is that? Give an answer one place behind the decimal.

(2.8 x 10 ²⁴) atoms

The Simple Things

100

What is a mole?

A unit used in chemistry to measure large quantities of small items.

200

What is Avogardo's number?

6.022 x 10²³

300

What does Avogadro's number represent? 

The number of atoms/molecules/formula units (particles) in 1 mole of something. 

400

How many grams are in 1 mole of Hydrogen (H)? 

1 gram

500

How many moles are in 4 grams of Helium (He)?

1 mole