Which of the following is the electron configuration of an electrically neutral alkaline earth metal a. 1s2 2s1 b. 1s2 2s2 2p2 c. 1s2 2s2 2p6 3s1 d. 1s2 2s2 2p6 3s2 3p6 4s2 i feel like the answer is d, but i’m not sure.

Apiece of copper has a temperature of 75.6 0c. when the metal is placed in 100.0 grams of water at 19.1 0c, the temperature rises by 5.5 0c. what is the mass of the metal?

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 many moles of no2 will form when 3.3 moles of cu are reacted with excess hno3?