**PLZ PLZ HELP ITS A TEST AND DUE SOON I WILL GIVE BRAINLIST TO THE RIGHT ANSWER** Zn + 2HCI → H2 + ZnCl2

At STP, how many liters of hydrogen gas (Hz) will be produced if 31.2 g of zinc is allowed to react with excess hydrochloric acid?
A)10.7L
B)2.82 L
C)9.66 L
D)4.30 L

Compared with the freezing-point depression of a 0.01 m c6h12o6 solution, the freezing-point depression of a 0.01 m nacl solution is

If 1.8 l of water is added to 2.5l of a 7.0 m koh solution, what is the molarity of the new solution

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)