Chemical Equations

What is changed in a chemical reaction like this one? 
NaOH + HCl   →  NaCl + H₂O

• the number of atoms is changed
• molecules and compounds are changed 
• atoms are changed
• elements are changed 

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What coefficient should go in the blank space to balance the chemical equation? 
2Al  +____  HCl   →    2AlCl₃  +  3H2

• 2
• 4
• 3
• 6

Tags

NGSS.MS-PS1-5

In chemical reactions, what does the principle of conservation of mass mean?

• Matter is not created or destroyed.
• The total mass of the reactants is greater than the total mass of the products.
• The total mass of the reactants is less than the total mass of the products.
• Matter is not changed.
  

Tags

NGSS.MS-PS1-5

Identify the reactant(s) and product(s) of the reaction.

• All three are reactants and none are products.
• Hydrogen and water are the reactants, and oxygen is the product.
• Water and oxygen are the reactants, and hydrogen is the product.
• Hydrogen and oxygen are the reactants, and water is the product.
  

Which is the Law of Conservation of Matter?

• matter cannot be created or destroyed, it only changes form
• matter can be created but it cannot be destroyed, it never changes form
• matter can be destroyed but it cannot be created, it usually just changes form
• matter is an unproven theory created by Hans Geiger

Tags

NGSS.MS-PS1-5

Identify the number in blue.

• Product

• Reactant

• Coefficient

• Subscript

Tags

NGSS.MS-PS1-1

What state of matter is this substance?

• solid

• liquid

• gas

• aqueous

Tags

NGSS.HS-PS1-3

NGSS.HS-PS1-5

How many atoms of nitrogen are in the compound shown above?

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-1

Which problem is balanced?
(Check ALL answers)

• PbO₂ + 2H₂
• SO₂ + H₂0 --> H₂SO₄
• 2Na + 2H₂O --> 2NaOH + H₂

Tags

NGSS.MS-PS1-5

CxHy +O₂ --> H₂O + CO₂

• Decomposition
• Double replacement
• Combustion
• Single Replacement

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2