Which of these pulls denser rocks towards Earth's center?

1. thermal energy

2. gravity

3. radiation

True or false If a material has a hardness of 8, it cannot be scratched by a material with a hardness of 7.

1. Directions: Select each correct answer. Biotic factors of an ecosystem could include which of the following? A. all types of plants B. the quantity of water available C. the temperature range D. all animal populations

The air in a balloon is heated up. Give two effects this has on the air particles.

According to the wave-mechanical model of the atom, an orbital is a region of the most probable location of (1) an alpha particle (3) an electron (2) a gamma ray (4) a proton

Give three examples of heterogeneous mixtures and three examples of solutions that you might use in everyday life.

If cobalt metal is mixed with excess sulfur and heated strongly, a sulfide is produced that contains 55.06% cobalt by mass. Calculate the empirical formula of the sulfide.

Calcium's atomic number is 20. it forms ions with 18 electrons. what is the electrical charge of a calcium ion?

The doldrums region on Earth is created by an amount of heating from the Sun that results in the rising of warm, moist air, low air pressure, cloudiness, high humidity, and numerous forms of severe weather, such as thunderstorms.

If a certain gas occupies a volume of 19 L when the applied pressure is 9.5 atm, find the pressure when the gas occupies a volume of 4.8 L

What is a type of force that will change an objects motion