Which of the following are likely to form a covalent bond?
1. two gold atoms
2. two neon atoms
3. hydrogen and oxygen atoms
4. magnesium and bromine atoms

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

How does the motion of particles in a gas change as the gas cools