I dont really understand this one either.

What mass of carbon dioxide is produced from the complete combustion of 4.50×10−3 g of methane?

For each of the compounds below, show that the charges on the ions add up to zero. a. kbr b. cao c. li(2)o d. cacl(2) e. alcl(3)

Astudent is asked to identify and element that is pale yellow brittle solid and does not conduct electricity. at which location in this periodic table would the element most likely be found?