Why isn't Earth a closed system

The total number of protons plus neutrons in an atom of ⁴⁵₂₀Ca is A.) 20 B.) 25 C.) 45 D.) 65

When a sound wave moves through a medium such as air, the motion of the molecules of the medium is in what direction (with respect to the motion of the sound wave?

Which system serves as the interface between the other spheres? a. geosphere b. hydrosphere c. atmosphere d. biosphere

In an experiment, 1 mol of propane is burned to form carbon dioxide and water. C3H8 + 502 3C02 + 4H20 1. How many moles of oxygen are needed for the reaction? A 3 mol B 1 mol C 5 mol D 10 mol

If a substance or object has the ability to do work, then it has

Charge 1 is - 30 μC, charge 2 is 5 μC, the distance between the charges is 8 cm, and they are located in a vacuum. If the third charge of 3 μC would be placed into position B, i. e.

For water vapor to turn back i to a liquid what do you do to it's temperature

How long will it take a car that is moving at 60 miles per hour to travel 120 miles?

Calculate the force required to give 380kg car an acceleration 10m/s square

A rock is dropped from a sea cliff, and the sound of it striking the ocean is heard 3.2 s later. If the speed of sound is 340 m/s, how high is the cliff?