71% of Earth's surface is covered in water, and 96% of its water is found in the oceans. Without water, Earth would likely be another boring rock in the sky.
Polar bears, naturally found at the North Pole, are sort of bipolar. The meter is defined as 1/10,000,000 of the distance between the North and South Pole.
Polarity is the "the state of having two opposite or contradictory tendencies, opinions, or aspects." In chemistry, polar molecules have one end that is positively charged and one side that is negatively charged.
As a polar solvent, water separates other polar and charged substances (like this NaCl salt) and helps them dissolve.
Life as we know it requires a polar solvent. Our blood is 90% water and helps transport polar salts, minerals, and proteins.
When oxygen pulls electrons away from hydrogen, it creates partial positive and partial negative poles. These partial poles are represented by the Greek lowercase delta, 𝛿. The 𝛿+ from hydrogen in one water molecule will react with the 𝛿- from oxygen in another water molecule. This interaction is known as a "hydrogen bond." Most of the unique and significant properties of water, including many of its life sustaining properties, can be attributed to hydrogen bonding.
Hydrogen bonding can only occur at specific angles. When water freezes, it locks water molecules into a specific shape that is actually less dense than liquid water. This abnormal property allows ice to float.
When scientists measure mass, they often use the "gram" as their reference unit. What exactly is a gram? Originally, the gram was based on the mass of 1 cubic centimeter of water at 4°C. Water is so important to our species, that we compare all other masses to water.
1g = 1000 mg
1g = 0.001 kg
It takes a lot of energy to break the hydrogen bonds that keep water molecules together. Because of these hydrogen bonds, water exists as a liquid for a large range of temperatures. This prevents our blood from boiling or freezing even with large variations in air temperature. The Celsius scale is based on these important temperatures for water.
Why is the temperature at the beach so much lower than the temperature inland? A big part of those temperatures is based on the specific heat of water. Specific heat is the amount of energy that a substance can absorb before it changes temperature. Metals have low specific heat, and will get hot quickly when exposed to heat; water has a relatively large specific heat (primarily because of hydrogen bonding) and requires much more energy to warm up. The energy from the sun is easily absorbed by the ocean, while the concrete in urban areas is more likely to radiate into its surroundings.
4.187 Joule = 1 calorie
The amount of energy needed to raise 1 gram of water by 1 °C is called a "calorie".
1000 calories = 1 kCal = 1 Calorie
Our evolutionary ancestors came from aquatic life. Water's high specific heat prevents big temperature changes in the ocean. Ice's unique density allows it to float above liquid water, which creates an insulating barrier for the water below it. Lakes freeze from the top down, allowing life to survive until warmer seasons arrive.
Our "fishapod" ancestors from 375 million years ago bridged the gap between sea and land life thanks to the unique freezing properties of water.
All of the water on the globe can be condensed to the big sphere; the tiny sphere of fresh water is far smaller in volume.
Dihydrogen Monoxide warnings might falsely give the public the impression that water is dangerous. Jokes aside, our access to potable water is dwindling and may prove to be a massive socioeconomic issue in the future. Global climate change has shifted weather patterns and made some areas more dry (California) while others are flooding (New Orleans, Miami, and even New York City). Water is the standard for life, and we need to treasure it.
Dihydrogen Monoxide is known to the CDC as a hazard capable of asphyxiation or tissue damage. DHMO is a constituent of many known toxic substances, diseases and disease-causing agents, environmental hazards and can even be lethal to humans.
What is the molar mass of water? (hint: add the molar mass of 2 hydrogens and 1 oxygen)
EXTRA CREDIT (up to 5 points): Practice unit conversions of grams to moles. Do you remember what a mole is? Write the definition (1 pt) and follow the examples to perform the following calculations (4 pts).
How many moles are in 25 grams of sodium chloride (NaCl)?
(Molar mass of NaCl = molar mass of Na + molar mass of Cl)
If you have 72 grams of water (H₂O), how many moles of water do you have?
(Molar mass of H₂O = 2 x molar mass of Hydrogen + 1 x molar mass of Oxygen)
How many grams are in 3.5 moles of carbon dioxide (CO₂)?
(Molar mass of CO₂ = molar mass of C + 2 x molar mass of Oxygen)
If you have 0.25 moles of potassium nitrate (KNO₃), what is the mass in grams?
(Molar mass of KNO₃ = molar mass of K + molar mass of N + 3 x molar mass of O)
East Valley High School
5525 Vineland Ave, North Hollywood, CA 91601
Phone: (818) 753-4400
Email: Isabel.partida@lausd.net
71% of Earth's surface is covered in water, and 96% of its water is found in the oceans. Without water, Earth would likely be another boring rock in the sky.
Polar bears, naturally found at the North Pole, are sort of bipolar. The meter is defined as 1/10,000,000 of the distance between the North and South Pole.
Polarity is the "the state of having two opposite or contradictory tendencies, opinions, or aspects." In chemistry, polar molecules have one end that is positively charged and one side that is negatively charged.
As a polar solvent, water separates other polar and charged substances (like this NaCl salt) and helps them dissolve.
Life as we know it requires a polar solvent. Our blood is 90% water and helps transport polar salts, minerals, and proteins.
When oxygen pulls electrons away from hydrogen, it creates partial positive and partial negative poles. These partial poles are represented by the Greek lowercase delta, 𝛿. The 𝛿+ from hydrogen in one water molecule will react with the 𝛿- from oxygen in another water molecule. This interaction is known as a "hydrogen bond." Most of the unique and significant properties of water, including many of its life sustaining properties, can be attributed to hydrogen bonding.
Hydrogen bonding can only occur at specific angles. When water freezes, it locks water molecules into a specific shape that is actually less dense than liquid water. This abnormal property allows ice to float.
When scientists measure mass, they often use the "gram" as their reference unit. What exactly is a gram? Originally, the gram was based on the mass of 1 cubic centimeter of water at 4°C. Water is so important to our species, that we compare all other masses to water.
1g = 1000 mg
1g = 0.001 kg
It takes a lot of energy to break the hydrogen bonds that keep water molecules together. Because of these hydrogen bonds, water exists as a liquid for a large range of temperatures. This prevents our blood from boiling or freezing even with large variations in air temperature. The Celsius scale is based on these important temperatures for water.
Why is the temperature at the beach so much lower than the temperature inland? A big part of those temperatures is based on the specific heat of water. Specific heat is the amount of energy that a substance can absorb before it changes temperature. Metals have low specific heat, and will get hot quickly when exposed to heat; water has a relatively large specific heat (primarily because of hydrogen bonding) and requires much more energy to warm up. The energy from the sun is easily absorbed by the ocean, while the concrete in urban areas is more likely to radiate into its surroundings.
4.187 Joule = 1 calorie
The amount of energy needed to raise 1 gram of water by 1 °C is called a "calorie".
1000 calories = 1 kCal = 1 Calorie
Our evolutionary ancestors came from aquatic life. Water's high specific heat prevents big temperature changes in the ocean. Ice's unique density allows it to float above liquid water, which creates an insulating barrier for the water below it. Lakes freeze from the top down, allowing life to survive until warmer seasons arrive.
Our "fishapod" ancestors from 375 million years ago bridged the gap between sea and land life thanks to the unique freezing properties of water.
All of the water on the globe can be condensed to the big sphere; the tiny sphere of fresh water is far smaller in volume.
Dihydrogen Monoxide warnings might falsely give the public the impression that water is dangerous. Jokes aside, our access to potable water is dwindling and may prove to be a massive socioeconomic issue in the future. Global climate change has shifted weather patterns and made some areas more dry (California) while others are flooding (New Orleans, Miami, and even New York City). Water is the standard for life, and we need to treasure it.
Dihydrogen Monoxide is known to the CDC as a hazard capable of asphyxiation or tissue damage. DHMO is a constituent of many known toxic substances, diseases and disease-causing agents, environmental hazards and can even be lethal to humans.
What is the molar mass of water? (hint: add the molar mass of 2 hydrogens and 1 oxygen)
EXTRA CREDIT (up to 5 points): Practice unit conversions of grams to moles. Do you remember what a mole is? Write the definition (1 pt) and follow the examples to perform the following calculations (4 pts).
How many moles are in 25 grams of sodium chloride (NaCl)?
(Molar mass of NaCl = molar mass of Na + molar mass of Cl)
If you have 72 grams of water (H₂O), how many moles of water do you have?
(Molar mass of H₂O = 2 x molar mass of Hydrogen + 1 x molar mass of Oxygen)
How many grams are in 3.5 moles of carbon dioxide (CO₂)?
(Molar mass of CO₂ = molar mass of C + 2 x molar mass of Oxygen)
If you have 0.25 moles of potassium nitrate (KNO₃), what is the mass in grams?
(Molar mass of KNO₃ = molar mass of K + molar mass of N + 3 x molar mass of O)
East Valley High School
5525 Vineland Ave, North Hollywood, CA 91601
Phone: (818) 753-4400
Email: Isabel.partida@lausd.net