Untitled Deck Flashcards
(21 cards)
Why is water considered a polar molecule?
Water is considered a polar molecule because it has a polar covalent bond. Partial negative charge on the oxygen atom and partial positive charges on the hydrogen makes water a polar molecule.
What are the bonds between water molecules called?
The bonds between water molecules are called hydrogen bonds. Due to the polarity of water molecules, the positive hydrogen of one water molecule is attracted to the negative oxygen of another water molecule, forming a hydrogen bond.
Distinguish cohesion from adhesion.
Cohesion refers to the attraction between water molecules themselves while adhesion describes the attraction between water molecules and other substances.
What is transpiration?
Transpiration is the process of plants losing water through their leaves. Cohesion and adhesion of water molecules, along with transpiration, allow trees to transport water from their roots to their leaves, even to great heights.
Why does ice float?
As water cools, its density increases, meaning it becomes more compact. However, this reverses at 4°C. Below 4°C, water molecules begin to form a crystal lattice structure. This structure is less dense than the liquid state, causing ice to float on water.
What does it take so much energy to heat water?
Water takes a long time to heat up because it has a high specific heat capacity. This means it needs a lot of energy to break the strong bonds between its molecules. Living near a body of water can help lower temperatures, making weather less extreme.
What is the percentage of water in a human body?
On average, the human body is about 60% water.
Why does water have such a high heat of vaporization?
Water has a high heat of vaporization because it takes a lot of energy to break the strong hydrogen bonds between its molecules. When water evaporates, these bonds must be broken, requiring a lot of energy. This relates to evaporative cooling. When water evaporates, it takes heat energy with it, leaving the remaining water cooler.
What is the solute and solvent in a 3.5% salt solution?
In a 3.5% salt solution, the solute is the salt and the solvent is the water.
What are the two ions of water?
The two ions present in water are hydrogen ions (H+) and hydroxide ions (OH-).
Which one is usually measured?
Hydrogen ion concentration (H+) is typically measured in solutions. This is because the concentration of hydrogen ions directly determines the acidity of a solution.
What is the pH scale?
The pH scale measures how acidic or basic a solution is. A pH of 7 is neutral, while a pH below 7 is acidic and a pH above 7 is basic.
What do we call chemicals that can resist pH change?
Buffers are chemicals that can resist pH change. They are solutions that contain a weak acid and its conjugate base.
What is the pH range in human blood?
The normal pH of human blood is slightly basic. If the pH of the blood rises above 7.45, it is considered alkalosis. If the pH of the blood falls below 7.35, it is considered acidosis.
What pH buffers do we have in our body?
The primary pH buffers in the human body are the bicarbonate buffer system, the phosphate buffer system, and protein buffers. These buffers work together to keep the pH from getting too low or too high.
How does fast breathing affect the pH of your blood?
Fast breathing, also known as hyperventilation, can cause a decrease in blood pH, leading to respiratory alkalosis. When you breathe faster, you exhale more carbon dioxide, which reacts with water in the blood to form carbonic acid, lowering the blood pH.
What is the pH of your stomach?
The pH of your stomach is typically between 1.5 and 3.5. This highly acidic environment is necessary for breaking down food and activating digestive enzymes.
Why do people take TUMS?
TUMS actually is a buffer. It contains calcium carbonate, which reacts with stomach acid to neutralize it and raise the pH of the stomach.
In general, foods are normally considered acidic, neutral or basic?
Foods are generally considered acidic or neutral. Most foods have a pH below 7, making them acidic. However, some foods, like baking soda, are basic.
Why is the ocean acidifying?
The ocean is becoming more acidic because people are burning fossil fuels. This releases carbon dioxide into the air, which is then absorbed by the ocean, harming marine life.
How does acid rain affect forests?
Acid rain can have a devastating impact on forests. When acid rain falls on trees, it can damage their leaves and needles, making it difficult for them to photosynthesize.
