Which of the following could have the electron configuration 2.8?
i. sodium (na) atom
ii. lithium (li) ion
iii. oxygen (o) ion
iv. neon (ne) atom
v. sulfur (s) ion

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

Right anwser gets marked brainliest newton's discovery concerning how fast an object will change speed is the: 1st law 2nd law 3rd law universal gravitation

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)