How much heat is evolved when 22.5 grams of a food sample changes the temperature of 0.42 kg of water by 4.4 degree C. Assume specific heat to be 4.18 J/g/C

What is the empirical formula of a compound that is 40% sulfur and 60% oxygen by weight? a. so b. so3 c. so2 d. s6o4

What was the ratio im the formula for the iron (ll) oxide

Does helium want to gain or lose any electrons

How many mL of 1.0M CrCl3 solution would be necessary to precipitate all of the Pb2 + from 50mL of. 90M solution. 2CrCl3 + 3Pb (NO3) 2 - --> 3PbCl2 + 2Cr (NO3) 3A.) 10B.) 20C.) 30D.) 60

Are all atoms (elements) neutral? And if not, how is the amount of electrons discovered?

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?