Law of Conservation of Mass

Matter can not be created nor destroyed: it can only be

• Destroyed a little bit
• Invisible
• Transformed, changed
• None of the above

Tags

NGSS.MS-PS1-5

The number to the lower side of an element is a 

• Subscript
• Superscript
• Coefficient
• Charge

The 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

Which of these is not a chemical reaction?

• Burning of wood
• Milk going bad
• Mixing vinegar and baking soda
• Melting of ice

Tags

NGSS.MS-PS1-2

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-PS1-2

NGSS.MS-PS1-5

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-PS1-2

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

Measure of the amount of matter 

• mass
• volume
• weight
• density