Which of one of these are balanced? Please explain. I'll give brainliest. 1. 3 Al + 2 O2 = 3 Al2 O3
2. 4 NH3 + 5 O2 = 4 NO + 6 H2O
3. 2 Fe S + 7 O2 = Fe2 O3 + 2 SO2

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.

How many absorptions would you expect to observe in the 13c nmr spectra of the following molecules? a) 3-chloropentane b) cis-4-methyl-2-pentene