Chemical Reactions

In a chemical ​ equation, the substances that undergo a chemical reaction are called the ​ (a)   and the new substances formed are called the ​ (b)   . The law of conservation of mass states that ​ ​ (c)   cannot be created or destroyed. Therefore, the atoms of the reactants must ​ (d)   the atoms of the products.

• reactants
• products
• matter
• equal
• molecules

Tags

NGSS.MS-PS1-5

We took vinegar and baking soda and made salt, carbon dioxide, and water.  Vinegar and baking soda are the

• mixtures
• elements
• reactants
• products

A student combines vinegar and baking soda.  They discover that a gas is given off.  What does this gas represent?

• element
• reactant
• product
• steam

The substance(s) that the chemical reaction starts with, like ingredients or the parts to be put together are called:

• subscripts

• products

• reactants

• coefficients

What is the definition of a chemical change?

• A chemical change is a process in which substances remain the same with no change in properties.

• A chemical change is a process in which substances are converted into different substances with opposite properties.

• A chemical change is a process in which one or more substances are converted into different substances with different properties.

• A chemical change is a process in which substances are converted into different substances with the same properties.

Which example best describes a physical change?

• iron rusting

• charcoal burning

• an ice cube melting

• a marshmallow burning

Coefficients tell the number of __________ in a formula.

• Molecules

• Atoms

• Elements

• Oxygen

The following tells us the number of molecules that are present in an equation.

• coefficient

• subscripts

• elements

What does the following represent?

• coefficient

• subscript

• elements

A subscript is the small number below the element symbol that tells the number of _______ of that element.

• atoms

• valence electrons

• protons

• elements