How many valence electrons does a neutral atom of silicon have?

At STP between 4.0 g of helium and 44.0 g of carbon dioxide Borne helium and carbon dioxide will have the same number of molecules Helium will have more molecules than carbon dioxide Carbon dioxide will have more molecules than helium Insufficient

True or false table salt is an example of a substance

Who wrote the first modern chemical textbook?

A 58.5 g sample of glass is put into a calorimeter (see sketch at right) that contains 250.0 g of water. The glass sample starts off at 91.2 °C and the temperature of the water starts off at 19.

Which of these contain a single long dna molecule? A) gene B) Nucleotide C) chromosone D) Deoxyribose

Which of the following has the greatest first ionization engergy li, be, b or c

If we know that 10.0 cm3 of ice has a mass of 9.19 g what is the density of ice

1. The is the particle in the nucleus of the atom that carries a positive charge and is counted to identify the atomic number. What's the answer

How many grams are there in 5.00 moles of lead Pb?

A large body in space that orbits a star and does not produce light of its own