Using the reaction, calculate the moles of hydrogen gas produced from the reaction of 4.5 moles of zinc: Zn+2HCl -> ZnCl2+H2

A. 1.0 mols H2
B. 2.0 mols H2
C. 4.0 mols H2
D. 4.5 mols H2

Scientists often deal with numbers that are either very large or very small. for example, the radius of the sun is approximately 696,000 kilometers, while bacterial cells are as small as 1.9 × 10-4 millimeters. express each of these numbers in an alternate form.