4. How many mL of a 0.150 M sodium iodide solution must be added to 75.0 mL of a 0.250 M lead (11) nitrate solution to precipitate all of the lead?
5. The neutralization of 25.0 mL of 0.24 M hydrochloric acid requires 5.0 mL of barium hydroxide.
What is the molarity of the barium hydroxide solution?

Calcium hydride (cah2) reacts with water to form hydrogen gas: cah2(s) + 2h2o(l) → ca(oh)2(aq) + 2h2(g) how many grams of cah2 are needed to generate 45.0 l of h2 gas at a pressure of 0.995 atm and a temperature of 32 °c?

How far is the region from the equator or control climate

Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size