Why is titanium more expensive than iron

What is evaporation? Describe what happens at the molecular level during evaporation.

jasenka [17]

Evaporation happens when atoms or molecules escape from the liquid and turn into a vapor. Not all of the molecules in a liquid have the same energy. Sometimes a liquid can be sitting in one place (maybe a puddle) and its molecules will become a gas. That's the process called evaporation. It can happen when liquids are cold or when they are warm. It happens more often with warmer liquids. You probably remember that when matter has a higher temperature, the molecules have a higher energy. When the energy in specific molecules reaches a certain level, they can have a phase change. Evaporation is all about the energy in individual molecules, not about the average energy of a system. The average energy can be low and the evaporation still continues.

6 0

3 years ago

Why does surface area of a reactant influence the rate of the reaction?

telo118 [61]

because it can influence how frequently and sufficiently the particles collide depending on the space it has to do so, for example a large surface area would be have a slower rate of reaction and a lower temperature. (the rate of reaction in terms of concentration, it is diffused from high to low)

7 0

3 years ago

A 1.85 kg textbook is sitting on a bookshelf 2.23 m above the floor. How much potential energy does it have?

neonofarm [45]

Answer:

$\boxed {\boxed {\sf 40.4299 \ Joules}}$

Explanation:

Potential energy is energy due to position. It is the product of mass, height, and acceleration due to gravity.

$PE= m \times g \times h$

The mass of the textbook is 1.85 kilograms. Assuming this is on Earth, the acceleration due to gravity is 9.8 meters per square second. The height is 2.23 meters.