How many moles are there in 5.75 x 10^24 atoms of aluminum

You weigh three samples of the same metal, and find their masses to be 35.71 g, 39.04 g, and 40.81 g. the corresponding volumes are 3.9 ml, 4.5 ml, and 4.5 ml. what is the density, d, of the metal?

Which of the following results in a chemical change in matter?

Select all the characteristics that will probably yield an ionic bond. Each answer refers to two atoms, Atom X and Atom Y. Atom X is referred to first, and Atom Y is referred to second. A. low E. N., low E. N. B. high E. N., low E. N. C. high E. N.

Sodium atoms emit light with a wavelength of 330 nm when an electron moves from a 4p orbital to a 3s orbital.

Which statement best explains the backward motion of the boat as the person moves forward a: every mass exert a force on every other mass b: an object at rest tends to stay at rest c: friction opposes the motion of an object d: for every action

Which statement is the best example of pseudoscience? A. J. joined a group that studies phrenology. Kathleen joined a group that studies endangered species. Joe joined a group that studies herbal remedies.

How many grams of sodium nitrate (NaNO2) will dissolve in 100g of water at 20°C?

Caffeine is about 10 times as soluble in hot water as in cold water. A chemist puts a hot-water extract of caffeine into an ice bath, and some caffeine crystallizes. Is the remaining solution saturated, unsaturated, or supersaturated and why?

Students in a science class learn that groundwater is an important source of drinking water for many communities. They construct a model to study how leaking chemicals from a landfill can affect groundwater.

Given the energy levels of electrons in a hydrogen atom (table), rank the photons emitted by the following electron transitions from longest to shortest wavelength. n=4 to n=3 n=4 to n=2 n=2 to n=1 n=3 to n=1