Why can't elements be broken into simpler substances?

A solution is made by mixing 127. g of acetyl bromide CH3COBr and 90. g of heptane C7H16. Calculate the mole fraction of acetyl bromide in this solution. Round your answer to 3 significant digits.

What does variable mean

Mendeleev used his periodic table of elements to

What type of waves move energy forward, but the source moves up and down? A) medium waves B) particle waves C) transverse waves D) longitudinal waves

Mg (oh) 2chemical name

Which of these molecules is least likely to form a hydrogen bond with a water molecule

George is writing an essay about the role of observation and inference in the development of the atomic theory. He wants to explain why it was more difficult to observe the presence of neutrons in atoms.

Which pair of statements below is correct? Multiple Choice An octet is formed via ionic bonding when one or more valence electrons are transferred from one atom to another.

If wave A has a frequency of 4.60 x 10^14 s-1, what is the wavelength in nanometers (show your work) ?

What is the mass in grams of 85.32 mL of blood plasma with a density of 1.03 g/mL?