Post CFA Chemistry

Which occurs when atoms link together in news ways to create a substance different from the original substances?

• A physical change

• A nuclear reaction

• a chemical change

• an inversion

A physical change occurs when a substance _____. 

• breaks into individual elements
• becomes a new substance
• changes from an acid to a base
• changes shape, size, and form

Which of the following are physical properties

• Color change, temperature change, and odor production

• Change in size, shape, state, color, and temperature

• Formation of a precipitate, loud noise, light, heat and odor

• Change in size, color and temperature only

Which are chemical properties?

• Change in size, shape, color, temperature and state of matter.

• Formation of a precipitate only

• Formation of a precipitate, odor, loud noise, heat and light and gas.

• Formation of color, temperature and odor only.

What are the phases of matter?

• Solid and Liquids

• Liquids and Gases

• Solids, liquids and gas

• Solid, liquid, gas and plasma

Releasing heat into the surrounding is an ___________________ reaction

• Exothermic

• Endothermic

• Kinetic Energy

• Thermal Energy

Absorbing heat from the surroundings is an ___________________ reaction

• Exothermic

• Endothermic

• Kinetic Energy

• Thermal Energy

The rate of a chemical reaction is NOT affected by which of the following:

• temperature (high go faster and low goes slower)

• concentration

• particle size (surface area)

• All of these affect reaction rates

What is the law of conservation of mass?

• Matter is created by a chemical reaction

• Matter is neither created nor destroyed in a chemical reaction.

• Matter is destroyed in a chemical reaction

Where are coefficients placed to balance a chemical equation?

• Behind first element

• In front of last element

• In front of element that needs the change

• Behind the element that needs the change