What happens to molecules when air heats? What happens when air is heated or cooled? So air, like most other substances, expands when heated and contracts when cooled. Because there is more space between the molecules, the air is less dense than the surrounding matter and the hot air floats upward. This is the concept […]
Why is Group 15 called nitrogen?
Why is Group 15 called nitrogen? The Group 15 elements are generally known as the nitrogen family. All of the elements of this family have five electrons in their outermost energy level. This group is divided into nonmetals, semimetals, and metals by characteristic. Nitrogen is a diatomic gas and phosphorus is a solid. Why is […]
What are some examples of physical and chemical properties?
What are some examples of physical and chemical properties? Physical properties include color, density, hardness, and melting and boiling points. A chemical property describes the ability of a substance to undergo a specific chemical change. What are the physical properties of materials? A material’s physical properties denote the physical state of materials that are exclusive […]
Which US president served 3 terms?
Which US president served 3 terms? Roosevelt won a third term by defeating Republican nominee Wendell Willkie in the 1940 United States presidential election. He remains the only president to serve for more than two terms. What was the name of Franklin Roosevelt’s foreign policy? The main foreign policy initiative of Roosevelt’s first term was […]
What is an example of a good hypothesis?
What is an example of a good hypothesis? Here’s an example of a hypothesis: If you increase the duration of light, (then) corn plants will grow more each day. The hypothesis establishes two variables, length of light exposure, and the rate of plant growth. An experiment could be designed to test whether the rate of […]
Is it better to have a high or low coefficient of friction?
Is it better to have a high or low coefficient of friction? In short, rougher surfaces tend to have higher effective values whereas smoother surfaces have lower due to the friction they generate when pressed together. Most dry materials in combination have friction coefficient values between 0.3 and 0.6. Which coefficient of friction should I […]
Which one is more stable O or O 2?
Which one is more stable O or O 2? 1 Answer. O2+ is more stable than O2-. Because According to molecular orbital theory O2+ has 15 electrons &it has one electron in antibonding orbital. In the case of O2- 17 electrons are present &3 electrons are present in antibonding orbitals. Why O2 ion is more […]
Could we manipulate the Higgs field?
Could we manipulate the Higgs field? If the discovery of the Higgs boson particle pans out, will even more mind-bending technologies result? Theoretically, it’s possible, says Arizona State University physicist Lawrence Krauss; but practically, it’s unlikely. “If you could manipulate the Higgs field locally, you’d have a great ‘Star Trek’ device. What exactly is the […]
What is the osmotic pressure of blood?
What is the osmotic pressure of blood? Types of fluids Oncotic pressure values are approximately 290 mOsm per kg of water, which slightly differs from the osmotic pressure of the blood that has values approximating 300 mOsm /L. Which of the following blood pressure readings would be indicative of hypertension? Blood pressure categories Normal: A […]
What happens when oil spills on land?
What happens when oil spills on land? As spilled oil on land prevents water absorption by the soil, spills on agricultural locations or grasslands have the effect of choking off plant life. Berms and trenches can be used to contain the spill, as long as their use does not allow the oil to leach into […]