Sort these elements into pairs that would most likely exhibit similar chemical properties. li, k, o, he, se ar

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.

One similarity and one difference between an element and a mixture of elements

Which of the following is in the lanthanide family? a) uranium b) promethium c) silver d) gold