In an atomic model that includes a nucleus, positive charge is
a. located in the space outside the nucleus.
b. spread evenly throughout an atom.
c. concentrated at multiple sites in an atom.
d. concentrated in the center of an atom.

Calculate the number of moles of ethane in 100 grams

Which of the following is most likely true about water in chemical systems? a) water dissolves nonpolar ionic compounds. b) water dissociates ionic compounds. c) water dissociates covalent molecules. d) water dissolves nonpolar covalent substances.

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.