How much H2 gas at STP can be produced by
the reaction
2 Na(s) + 2 H2O(ℓ) −→ H2(g) + 2 NaOH(aq)
of 4.20 g of Na and excess water?

Cobalt-60 is an artificial radioisotope that is produced in a nuclear reactor and is used as a gamma-ray source in the treatment of certain types of cancer. if the wavelength of the gamma radiation from a cobalt-60 source is 1.00 × 10-3 nm, calculate the energy of a photon of this radiation.

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm

The organs inside the body and how they function together