Unit 1-3 Review

Which is a compound?

• sodium

• sugar

• nitrogen

• air

Two different liquids are poured together in an open container. Bubbles begin to form. After the bubbling stops, it is determined that the total weight of the two liquids is less than before they were poured together. Which best describes this observation?

• Some of the atoms during the reaction escaped into the air

• Some of the atoms during the reaction were destroyed.

• Some of the atoms during the reaction became heavier

• Some of the atoms during the reaction changed to a different kind of atom.

This is a chemical reaction for the decomposition of carbonic acid into water and

carbon dioxide.

H2CO3 → H2O + CO2

How does the reaction support the Law of Conservation of Mass?

• Several molecules of water are produced.

• The mass of carbon atoms is reduced during the reaction.

• The mass of the atoms in the reactant equals the mass of the atoms in the products.

• The mass of hydrogen atoms is the only thing that remains the same before and after the reaction.

Which disease is caused by a fungal infection?

• intestinal worms

• influenza

• chicken pox

• athlete’s foot

How are pandemics different than epidemics?

• Pandemics affect blood; epidemics affect skin

• Pandemics affect many countries or states; an epidemic is more localized

• Pandemics are caused by bacteria; epidemics are caused by viruses

• Pandemics are spread through the air; epidemics are spread through the water

Which is one possible human benefit from biotechnology research?

• producing crops that can grow in areas where they normally do not grow

• producing new types of disease-causing viruses

• increasing the ability to turn ocean water to freshwater

• creating new types of buildings that can withstand hurricanes

How has genetic engineering helped farming?

• by developing better fertilizer for crops

• by creating crops that resist some diseases

• by producing soil that makes crops grow better

• by producing faster ways to harvest crops

Which is the primary source of energy for most cells in the body?

• sugar

• fat

• protein

• vitamins

Which is classified as an element?

• carbon dioxide

• iron

• vinegar

• water

Which statement is true about a chemical reaction?

• The physical states of the atoms in the reactants determine the products.

• Some of the atoms in the reactants will be a part of the products.

• The number of atoms in the reactants determines the products.

• All of the atoms in the reactants will be a part of the products