Amixture is ( is/is not ) a chemical combining of substance?

There is an area in idaho named craters of the moon where most of the ground is covered with basalt, adark gray, igneous rock with no visibl crystals. what can you infer about the geographical history of the area?

The two naturally occurring isotopes of chlorine are 35cl (34.969 amu, 75.77%) and 37cl (36.966 amu, 24.23%). the two naturally occurring isotopes of bromine are 79br (78.918 rm amu, 50.69%) and 81br (80.916 amu, 49.31%). chlorine and bromine combine to form bromine monochloride, brcl. 1. how many peaks will be present in a mass spectrum for brcl? the four combinations of molecule possible given these four isotopes are: 81br37cl, 81br35cl, 79br37cl, and 79br35cl. 2. what are the masses of the four different brcl molecules? express the masses using six significant figures, in decreasing numeric order (highest to lowest), separated by commas.

Structure of the atoms: discovery of the nucleus in 1909i need answering all of these questions