Law of Conservation of Mass

How many Nitrogen atoms are in this chemical formula?

• 1

• 4

• 2

• 8

The Law of Conservation of Mass says that matter -

• can be destroyed a little bit.

• Invisible.

• cannot be created or destroyed.

• None of the above.

The small number to the lower side of an element is a

• Subscript

• Superscript

• Coefficient

• Charge

The large number in front of a compound or element is a

• Subscript

• Coefficient

• Superscript

• Charge

A chemical reaction is balanced when

• both sides have the same elements
• Both sides have the same  number of atoms
• Same subscripts
• Same coefficients

Tags

NGSS.MS-PS1-5

The coefficient in  3H₂O is

• 6
• 2
• 3
• 5

Tags

NGSS.MS-PS1-1

If reaction starts with 20g of reactants it should produce 

• a total of 40g of products
• a total of 10g of products
• a total of 80 g of products
• a total of 20g of products

Tags

NGSS.MS-PS1-5

How many Hydrogen atoms are in the following chemical formula?

• 4

• 1

• 8

• 16

In a reaction A + B ----> C,  reactant A has 5g and product  C has 9g. How many grams does reactant B should have? 

• 4g
• 5g
• 9g
• 14g

Tags

NGSS.MS-PS1-5

What will weigh more when a chemical change is complete?  The reactants before the chemical reaction, or the product after the reaction is complete?

• They both will weigh the same
• The product always weighs more than the reactant
• The reactant will weigh more than the product
• They both will loose mass after the reaction

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5