Atoms + Types of Bonds + Properties of Water Test Review

What type of bond is found IN water molecules?

• Polar Covalent

• Hydrogen

• Ionic

• Van der Waals

Answer explanation

Bonds between hydrogen and oxygen in water are covalent bonds. The two atoms are sharing their valence electrons.

Recall: This is a POLAR covalent bond since it is unequal sharing of the electrons

Water property responsible for water movement up the stem

• Adhesion and cohesion

• Less dense as solid

• Specific heat

• Surface tension

Answer explanation

Adhesion is the attraction of water molecules to other polar substances. The water is hydrogen bonded to the walls of the capillary tubes (xylem) of the plant.

Cohesion is the attraction of water molecules to other water molecules. The water is hydrogen bonded to another water molecule creating a “string” of like when you connect a barrel of monkeys.

Water property responsible for lake life surviving winter

• Adhesion and cohesion

• Less dense as solid

• Evaporative Cooling

• Surface tension

Answer explanation

Due to the hydrogen bonds, water molecules are unable to compact tightly which leaves space between the molecules and causes it to expand upon freezing making it less dense. This causes water to float to the surface creating a buffer to inhibit the lake from freezing which preserves life during winter.

Tags

NGSS.HS-ESS2-5

What type of bond is found BETWEEN water molecules?

• Covalent

• Hydrogen

• Ionic

• Van der Waals

Answer explanation

The bond WITHIN water between the oxygen and hydrogen is a covalent bond since the atoms are sharing electrons from their valence shells. This causes a partial positive charge at the hydrogen and a partial negative charge at the oxygen. Those partial charges lead to hydrogen bonds BETWEEN water molecules as the oxygen of one water is attracted to a hydrogen of another water.

What property of water is used by organism during sweating?

• Adhesion

• Cohesion

• Evaporative Cooling

• Less Dense as Solid

Answer explanation

Evaporative cooling is the act of water molecules absorbing the heat from the surface causing the water to evaporate (and taking the heat energy away from the organism).

Which end of the water molecule has a slightly positive charge?

• the oxygen end
• the hydrogen end
• both ends are slightly positive
• neither end is positive

Tags

NGSS.HS-ESS2-5

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

When water molecules stick easily to other water molecules, this is called what?

• cohesion
• adhesion
• solution
• polar molecule

Tags

NGSS.HS-ESS2-5

Water beads up on the surface of a penny because of what property?

• Adhesion
• High Surface Tension
• Universal Solvent
• Changes in Density

The fact that ice floats on liquid water is due to the fact that water's solid is ___________ than it's liquid form

• less polar
• more polar
• less dense
• more dense