If a piece of iron is placed in pure nitrogen, nothing happens. If the in is exposed to air, it begins to rust. What conclusion can you make about air, based on this observation?

The world population A. Is evenly distributed B. Will triple in 2050 C. Is unevenly distributed D. Is mostly concentrated in agricultural areas.

Which of the following statements is true? 1 Nitrogen leaves the atmosphere through precipitation. 2 Carbon dioxide is released into the atmosphere through plant leaves. 3 Carbon dioxide is inhaled by animals.

En saved Question 19 of 31 If a bat with a mass of 5 kg and acceleration of 2 m/s2 hits a ball whose massis 0.5 kg in the forward direction, what is the reaction force of the ball on the bat?

What can you observe to know that when clear methane gas is burned it is a chemical change? 1) Change of color 2) Formation of a precipitate 3) Change in mass 4) Formation of a gas 5) Change in temperature 6) Change in shape

What is the velocity of jet plane that flies 7200km east in 9 hours (in km/hr)

A 2.0-kilogram laboratory cart is sliding across a horizontal frictionless surface at a constant velocity of 4.0 meters per second east. What will be the cart's velocity after a 6.0-newton westward force acts on it for 2.

A boat floats with 25% of its volume under water. a. What is the boatâs density? b. If the boat was made from 500 kg of metal, what is the volume of the boat? (Assume the air in the boat has negligible mass and density) c.

Why does each mineral have their own property, different from every other mineral?

Earth's tallest mountain ranges are found at plate boundaries

Is a lung a living organism, why or why not?