Ch 19 Physical Science Test

A chemical reaction is:

• a physical change in matter

• a process where substances are transformed into new substances

• a method of separating mixtures

• a way to measure temperature

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Reactants are:

• substances that are produced in a chemical reaction

• substances that are present before a chemical reaction and take part in it

• the energy released during a reaction

• the products formed after a reaction

Tags

NGSS.MS-PS1-1

Products are:

• things that are made or grown to be sold

• substances before a reaction

• substances after a reaction

• substances that are broken down

Tags

NGSS.MS-PS1-2

__________ established that the total mass of the reactants always equals the total mass of the products. This is called the Law of Conservation of Matter.

• Lavoisier

• Newton

• Dalton

• Boyle

Tags

NGSS.HS-PS1-7

A chemical equation is:

• A mathematical expression

• A representation of a chemical reaction using symbols and formulas

• A type of physical change

• A list of laboratory equipment

A coefficient is:

• a variable in an equation

• a number before a substance

• a subscript

• an operation in mathematics

You can only add coefficients and can not add or take away subscripts because:

• Coefficients change the number of molecules, while subscripts change the identity of the substance.

• Subscripts are easier to change than coefficients.

• Changing coefficients changes the substance's identity.

• Coefficients and subscripts mean the same thing.

A balanced chemical equation is:

• an equation where the number of atoms of each element is equal on both sides

• an equation with more reactants than products

• an equation that does not follow the law of conservation of mass

• an equation with only one reactant

Tags

NGSS.HS-PS1-7

A mole is:

• a unit of mass

• a unit of amount of substance

• a type of chemical reaction

• a laboratory instrument

Molar mass is:

• the mass of one mole of a substance

• the number of atoms in a molecule

• the volume of one mole of a gas

• the charge of an ion