A hypothetical element has two main isotopes. One has a mass of "40 amu" and the other has a mass of 42 amu. If the atomic weight of this element is 40.78 amu, what is the percent abundance of the 42 amu isotope?

Hannah is writing a report on how albedo affects the global climate. she’s proofreading her passage for any factual errors. which sentence must hannah correct before submitting her report? earth receives energy from the sun. this energy drives many of the processes on earth, including its climate. some part of this energy is reflected by earth’s surface. we use the term albedo to describe the reflected energy. albedo of an object is the ratio of the reflected radiation to the total radiation reaching the object. a value of 0 means no energy is absorbed by the object, whereas a value of 1 means that all of the energy is absorbed. in this way, the albedo of an object can influence earth’s atmospheric temperature.

Acompound contains c, h, and o atoms. when 1.130 g of the compound is burned in oxygen, 1.064 g co2 and 0.3631 g h2o are produced. what is the empirical formula of this compound?

(1.6 × 10-19)(5.0 × 106) = c × 10d identify the missing numbers below to show the result of multiplying the numbers.