1.
This image specifically demonstrates one example of how ______________________ is beneficial to living organisms.
Correct Answer
B. Surface tension
Explanation
Surface tension is the property of a liquid that allows it to resist external forces and form droplets or maintain its shape. In the context of living organisms, surface tension is beneficial in various ways. For example, it helps insects like water striders walk on water without sinking by distributing their weight across the water's surface. It also allows plants to transport water and nutrients from their roots to other parts of the plant through capillary action. Additionally, surface tension enables certain organisms to create protective barriers or structures, such as the surface film produced by some aquatic organisms to trap oxygen or the bubbles formed by diving beetles for respiration.
2.
Adhesion leads to ________________, which is the characterisitc of water in which explains the molecular absoprtion of water into a root or stem of a plant.
Correct Answer
D. Capillary action
Explanation
Capillary action is the phenomenon where water is able to move against gravity in narrow spaces, such as the roots or stems of plants. This is due to the adhesive forces between water molecules and the walls of the narrow spaces, which allows water to be pulled up. This characteristic of water is explained by capillary action.
3.
Humans have physiologically adapted to sweat if the body temperature rises past ideal levels. The ability to do so helps cool the body down. The polarity of water allows water to have a high _________________________, which allows us to maintain homeostasis and survive as we are today.
Correct Answer
B. Specific heat
Explanation
The correct answer is "specific heat." Specific heat refers to the amount of heat energy required to raise the temperature of a substance by a certain amount. Water has a high specific heat, which means it can absorb a lot of heat energy before its temperature increases significantly. This property of water allows our bodies to maintain homeostasis by absorbing excess heat when we sweat, helping to cool us down and prevent overheating.
4.
During the water and string excitement, the factor keeping the water bonded to the string was the concept of _____________________.
Correct Answer
E. Adhesion
Explanation
The correct answer is adhesion. Adhesion is the force of attraction between different substances. In the case of the water and string excitement, the water molecules are attracted to the molecules of the string, causing them to stick together. This adhesion between the water and string is what keeps the water bonded to the string, overcoming the force of gravity.
5.
The first falling leaf of the season has tumbled from the air and landed on the top of the pond. It does not sink, but yet float on top of the surface. What is happening on a molecular level that is preventing the leaf from sinking?
Correct Answer
C. There is not enough weight to break the hydrogen bonds between water molecules at the surface of the water
Explanation
The leaf is able to float on the surface of the water because there is not enough weight to break the hydrogen bonds between water molecules at the surface. Hydrogen bonds are relatively weak compared to covalent bonds, but they are still strong enough to hold the leaf up due to the lack of weight placed upon them. The surface tension created by these hydrogen bonds allows the leaf to stay afloat.
6.
What type of bonds interconnect the molecules shown in this image?
Correct Answer
C. Hydrogen
Explanation
The molecules shown in the image are interconnected by hydrogen bonds. Hydrogen bonds occur when a hydrogen atom is bonded to a highly electronegative atom, such as oxygen or nitrogen, and is attracted to another electronegative atom nearby. These bonds are weaker than covalent or ionic bonds, but they play a significant role in determining the structure and properties of many molecules, such as water and DNA.
7.
Water molecules bond in a crystalline form as the temperature of water drops. This creates more space between water molecules. What characteristic of water does this change describe?
Correct Answer
B. Density
Explanation
As the temperature of water drops and it bonds in a crystalline form, the water molecules arrange themselves in a way that creates more space between them. This change in arrangement leads to a decrease in the density of water. Density refers to the amount of mass per unit volume, so when the density decreases, it means that the mass of water is spread out over a larger volume.
8.
Capillary action involves the following THREE properties of water: adhesion, ________________, and surface tension.
Correct Answer
D. Cohesion
Explanation
Cohesion is the correct answer because it is one of the three properties of water involved in capillary action. Cohesion refers to the attraction between molecules of the same substance, in this case, water molecules. This attraction allows water molecules to stick together, creating a continuous column or "capillary" within a narrow tube or porous material. Adhesion refers to the attraction between molecules of different substances, while surface tension is the property that allows water to form droplets and resist external forces. Density, polarity, and non-polarity are not directly related to capillary action.
9.
What is meant by the fact that water is a "polar" molecule?
Correct Answer
E. None of the above
Explanation
Water is considered a "polar" molecule because it has both a slightly positive charge and a slightly negative charge. This is due to the unequal sharing of electrons between the oxygen and hydrogen atoms in the water molecule. The oxygen atom attracts the shared electrons more strongly, giving it a slight negative charge, while the hydrogen atoms have a slight positive charge. Therefore, none of the options provided in the answer are correct.
10.
Which best describes how hydrogen bonds are created?
Correct Answer
A. The negative charge of an oxygen binds with the positive charge of a hydrogen on an adjacent molecule
Explanation
Hydrogen bonds are created when the negative charge of an oxygen atom in one molecule is attracted to the positive charge of a hydrogen atom in an adjacent molecule. This attraction is due to the difference in electronegativity between oxygen and hydrogen, with oxygen being more electronegative and therefore pulling the shared electrons closer to itself. This creates a partial positive charge on the hydrogen atom and a partial negative charge on the oxygen atom, allowing for the formation of a hydrogen bond.
11.
Fill in the blanks with the most appropriate answer:
" Oil is _______________ than water as well as ________________, with evidence being that oil sits on top of water as well as seperates from water."
Correct Answer
C. Less dense; non-polar
Explanation
Oil is less dense than water as well as non-polar, with evidence being that oil sits on top of water as well as separates from water.
12.
On large scale, the Earth is 75% water. What property of water provides the insulation and warmth of the Earth's surface?
Correct Answer
A. Specific heat
Explanation
Water has a high specific heat, which means it can absorb and store a large amount of heat energy without a significant increase in temperature. This property allows water to act as a buffer, regulating the Earth's temperature and providing insulation and warmth to the planet's surface. The high specific heat of water helps to moderate temperature changes on Earth, preventing extreme fluctuations and creating a more stable climate for life to thrive.
13.
Shaving cream, food coloring, and post cards make for a good time! Food coloring is added to the shaving cream and applied to a post card. Which property of water (water being the majority of food coloring + die) is directly responsible for the colorful design on the notecard?
Correct Answer
B. Capillary action
Explanation
Capillary action is the property of water that is directly responsible for the colorful design on the notecard. Capillary action is the ability of a liquid to flow in narrow spaces against the force of gravity. In this case, the water in the food coloring is able to flow through the small spaces in the shaving cream and be absorbed by the postcard, creating the colorful design.
14.
In relation to the ice cap, which property of water is this polar bear relying on?
Correct Answer
E. Density
Explanation
The polar bear is relying on the property of water known as density. Water has a higher density in its liquid form compared to its solid form (ice). This allows the polar bear to swim and move easily in the water, as the higher density of water provides buoyancy and support.
15.
Olympic event: Water on a Penny
Which property of water is directly responsible for maintaining the water bubble forming on the penny?
Correct Answer
B. Cohesion
Explanation
Cohesion is the property of water that is directly responsible for maintaining the water bubble forming on the penny. Cohesion is the attraction between water molecules, causing them to stick together. This cohesive force allows the water molecules to form a bubble on the penny's surface, as the water molecules are more attracted to each other than to the penny.