Someone. i would really appreciate it a newly discovered element, x, has two naturally occurring isotopes. 93.5 percent of the sample is an isotope with a mass of 268.9 u, and 6.5 percent of the sample is an isotope with a mass of 269.9 u. what is the weighted average atomic mass for this element?

268.5 u
269.0 u
269.8 u

Suppose that during that icy hot lab 65,000 j of energy were transferred to 450 g of water at 20°c what would have have been the final temperature of the water

This image is an example of a(n) a) atom. b) compound. c) mixture. d) molecule.

The characteristic of two different types of reactions are shown below. reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of and element. which statement is true about the atoms of the elements that participate in the two reactions? a: their identity changes in both reaction a and b. b: their identity changes in reaction a but not b. c: their identity changes in reaction b but not a. d: their identity remains the same.