The average atomic mass of a sample of an element X is 16.2u. What are the percentages of isotopes X (mass number 16, atomic number 8) and X (mass number 16, atomic number 8) in the sample?

Which best describes the convection currents in Earth's mantle? They transfer potential energy away from Earth's core toward its crust. They transfer thermal energy away from Earth's core toward its crust.

What is the most likely explanation for the change in population that occurred at 1.5 years?

Which electron configuration represents the electrons of an atom in an excited state? (1) 2-8-1 (3) 2-8-17-6 (2) 2-8-6 (4) 2-8-18-5

2. Explain the effect of: a. Adding or removing gas to a constant volume. What happens to the pressure? Is this a direct or indirect relationshin?

During an autopsy, all organs are removed from the body, weighed, and examined for any damage that might reveal information about the cause of death. True or False?

14. Two or more substances that are together but do not combine to form a new, pure substance.

A solution of a compound with a known extinction coefficient of 23,100 M-1cm-1 has an absorbance of 0.735 in a 1.30cm path length, what is the concentration of the solution

Balance the following equation with the smallest whole number coefficients. Choose the answer that is the sum of the coefficients in the balanced equation. Do not forget coefficients of "one". RbOH + H3PO4 → Rb3PO4 + H2O

What is the temperature of 100 liter container having 1 mole of an ideal gas at a pressure of 20 kilopascals

5.2*10^26 molecules of ch4 in volume