According to Bohr's model of the atom electrons behave like

Classify this reaction: 2al+n2-> aln.

When did stem cell research become known ? who discovered stem cell? what experiments or studies have been conducted so far?

Which best describes the present-day universe? opaque, expanding very slowly, stars produce heavy elements transparent, expanding at an accelerated rate, stars produce heavy elements opaque, expanding at an accelerated rate, stars produce only hydrogen and helium transparent, expanding very slowly, stars produce only hydrogen and helium