Balancing Chemical Equations

What coefficient should be used to make the following equation balanced?
N₂+O₂--> _NO 

• 1
• 2
• 3
• 4

What is the total number of atoms present in 5Na₃PO₄

• 5
• 40
• 55
• 8

The numbers needed to balance the equation are:

• 2, 7, 6, 4
• 2, 1, 3, 2
• 1, 1, 3, 2
• 2, 3, 1, 3

The numbers needed to balance the equation are:

• 2, 7, 6, 4
• 2, 1, 3, 2
• 3, 1, 1, 3
• 2, 3, 1, 3

The numbers needed to balance the equation are:

• 1, 1, 1, 2
• 1, 1, 2, 2
• 1, 1, 1, 1
• 2, 3, 1, 3

What is the right ratio of chemicals for the BCE (Balanced Chemical Equation)?__CO + __Fe₂O₃--> __Fe + __CO₂

• 3,1 --> 2,3
• 3,2 --> 1,1
• 3,2 --> 2,4
• 3,2 --> 2,1

Which number should go in the blank?
Mn + _ HNO₃ → Mn(NO₃)₂ + H₂

• 1
• 2
• 3
• 0

Which number should go in the blank?
Al(NO₃)₃ + _  NaOH -> Al(OH)₃ + 3 NaNO₃

• 1
• 2
• 3
• 0

How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl₂ + H₂

• 1
• 2
• 3
• 4

Balance this equation

_Al +_HCl --> _H₂ +_AlCl₃

• 2,6,3,2

• it's already balanced

• 4,12,3,4

• 2,1,4,5