A student is studying asbestos, a mineral that causes cancer in humans. One of the components of asbestos is silicon, a somewhat reactive element, that is the second most abundant element found in the Earth’s crust. Which characteristic of silicon is most closely related to its chemical reactivity? The atomic mass of silicon, which is 28.085 amu The atomic mass of silicon, which is 28.085 amu The 14 protons in each atom of silicon The 14 protons in each atom of silicon The 4 valence electrons in each atom of silicon The 4 valence electrons in each atom of silicon The density of silicon, which is 2.33 g/cm3

Astudent is given a sample of a blue copper sulfate hydrate. he weighs the sample in a dry covered porcelain crucible and got a mass of 23.875 g for the crucible, lid, and sample. the mass of the empty crucible and lid was found earlier to be 22.652 g. he then heats the crucible to expel the water of hydration, keeping the crucible at red heat for 10 minutes with the lid slightly ajar. on colling, he finds the mass of crucible, lid, and contents to be 23.403 g. the sample was changed in the process to very light clue anhydrous cuso4. if there are again 100.0 g of hydrate, how many grams of cuso4 are in it? how many moles of cuso4? (hint: molar mass of cuso4 = 159.6 g / mole. what per cent of the hydrate is cuso4? you may convert the mass of cuso4 to moles.)

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Consider the four elements above. which one of these elements will combine with oxygen in a 1: 1 ratio?