Calculations in chemistry

2H₂   +   O₂    −−〉 2H₂O
8.3 moles H₂ −−〉 ? moles H₂O

• 4.15
• 8.3
• 16.6
• 74.04

How many particles are in 13.5 grams of Beryllium?

• 1.5 particles
• 9 particles
• 4x10²³ particles
• 9x10²³ particles

2 NaClO₃ (s) --> 2NaCl (s) + 3 O₂ (g)  
12.00 moles of NaClO₃ will produce how many grams of O₂?

• 256 g of O₂
• 576 g of O₂
• 288 g O₂

2CO  +  O₂  −-> 2CO₂
How many liters of carbon dioxide are produced from 10L of carbon monoxide?

• 10
• 20
• 1
• 5

N₂ +  3H₂ −->  2NH₃ 
How many moles of ammonia are produced when 3 moles of nitrogen react with hydrogen?

• 6 moles Ammonia
• 1.5 moles ammonia
• 9 moles ammonia
• 9 moles hydrogen

Mole ratios are obtained from the

• balanced chemical equation
• periodic table
• molar mass

Calculate the number of gold atoms in a 4 mole sample of gold.

• 2.41x10²⁴
• 3.01x10²³
• 4.82x10²⁴
• 6.02x10²³

Calculate the number of moles of Aluminum in a 2.04 mole sample of aluminum oxide, Al₂O₃.

• 2.04 moles
• 4.08 moles
• 6.12 moles
• 1.02 moles

Calculate the mass of oxygen present in a 55g sample of Aluminum oxide, Al₂O₃.

• 29.28
• 19.95
• 11.36
• 32.33

What is the molarity of 2.5 mol of NaOH in 12.0 L of solution?

• 0.21 M
• 30 M
• 4.8 M
• 20.8 M