The reaction of solid zinc metal and hydrochloric acid produces zinc chloride and hydrogen gas as shown below. How many grams of zinc metal would I need to produce 45 mL of hydrogen gas at a pressure of 2.736 atm and 27°C? Zn(s) + HCl(aq) à ZnCl2(aq) + H2(g)

(unbalanced)

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

The following reaction shows sodium carbonate reacting with calcium hydroxide. na2co3 + ca(oh)2 → naoh + caco3 how many grams of naoh are produced from 20.0 grams of na2co3? (molar mass of na = 22.989 g/mol, c = 12.01 g/mol, o = 15.999 g/mol, ca = 40.078 g/mol, h = 1.008 g/mol) 12.2 grams 15.1 grams 24.4 grams 30.2 grams

Identify arrows pointing to bonding electrons. done h-0-0-h ) intro