After completing your observations, is 21 days enough time to view all the phases of the Moon? Explain.

A metal tank contains three gases: oxygen, helium, and nitrogen. If the partial pressures of the three gases in the tank are 5.75 atm of O2, 7 atm of N2, and 2.25 atm of He, what is the total pressure inside of the tank

Which of the following descriptions about standard addition and internal standards are NOT correct? a) Internal standard is useful when the matrix in the unknown is complicated.

an element has atomic numer 10 and an atomic mass of 20. how many neutrons are in the atom of this element

Is utensils a substance homogeneous mixture or heterogeneous mixture

When an election is removed a second electron is call the blank energy

Two compound samples are found to have the same mass percentages of the same elements. what can you conclude about the two samples

Sodium hypochlorite (Na xCl yO z) is the active ingredient in household bleach. A 250.0 g sample of sodium hypochlorite contains 77.2 g sodium, 119.1 g chlorine, and the remainder is oxygen. Calculate the empirical formula of sodium hypochlorite.

The tapeats sandstone in the grand canyon is an example of a clastic sedimentary rock. such clastic sedimentary rocks can be distinguished from biochemical sedimentary rocks by

An ice cube and a scoop of table salt are left outside on a warm, sunny day. Explain why the ice cube melts and the salt does not

Which atomic orbitals overlap to form the C-O bond of dimethyl ether, (CH3) 20? O c 2sp^3 + 2sp^3 OC 2sp^2 + 0 2p O c 2sp^2 + 0 25p^2 O C 2sp^3 + O 2sp?