Law of Conservation of Mass Test

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

• Subscript

• Superscript

• Coefficient

• Charge

A chemical reaction is balanced when

• both sides have the same elements

• Both sides have the same  number of atoms of each element

• Same subscripts

• Same coefficients

Tags

NGSS.MS-PS1-5

The number in front of a compound or element is a 

• Subscript

• Coefficient

• Superscript

• Charge

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

NGSS.MS-PS1-5

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

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

Since gasses weigh nothing, when they are produced in a reaction they do not have to be accounted for.  

• True

• False

Which are the reactants in the following reaction?
2Mg + O₂ ---> 2MgO 

• Mg and O

• MgO

• Mg and MgO

• O and MgO

How many oxygen atoms are in this chemical formula?

• 6 oxygen atoms

• 2 oxygen atoms

• 3 oxygen atoms

• 4 oxygen atoms

Tags

NGSS.MS-PS1-1