What quantity of gas, in moles, is contained in 1.56 L at STP?

What is the result of multiplying (2.5 × 1010) × (2.0 × 10-7)? a. 5.0 × 103 b. 5.0 × 10-3 c. 5.0 × 1017 d. 5.0 × 10-17

How many liters of hydrogen gas will be produced at stp from the reaction of 7.179×10^23 atoms of magnesium with 54.219g of phosphoric acid (h3po4) the equation is 3mg + 2h3(> mg(po4)2+3h2

Water's surface tension and heat storage capacity are accounted for by its a) orbitals b) weight c) hydrogen bonds d) mass e) size